Author Topic: maunal specs question on velocity  (Read 1345 times)

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Offline Scibaer

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maunal specs question on velocity
« on: April 16, 2008, 09:26:35 AM »
Ok, this may be a dumb questions ( I know, dont say it, lol ) but , are the suggested specs for velocity, given if you follow the reciept, accurate for velocity?
 what Im thinking, if I handload up some rounds, and test thru my chrono ( i need to buy one first ) will I see relatively close results ? to what is published ?

glenn

Offline Siskiyou

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Re: maunal specs question on velocity
« Reply #1 on: April 16, 2008, 09:58:08 AM »
I would say no because of the variables involved.  I had developed some loads for the .270 Winchester and fired them across the Chrony.  Rifle #1 a Savage 110 consistently obtained 30 feet per second more velocity then rifle #2 a Remington 700. 

Depending on the lab that developed the data it is very hard for the reloader to match the temperature, RH, barometric pressure, and elevation.  You might come close, but it is difficult to duplicate.

I recently corresponded with a member who had the sister rifle to one of mine.  We had achieved similar results with the same powder and bullet.  I believe a ‘similar’ result is a good goal.
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Offline corbanzo

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Re: maunal specs question on velocity
« Reply #2 on: April 16, 2008, 10:47:37 AM »
There are too many variables.  My loads are all over the chart compared to the manuals.  Some keep up, many are slower.  I can obtain their velocities... but I am over their stated maximum a lot of the time. 
"At least with a gun that big, if you miss and hit the rocks in front of him it'll stone him to death..."

Offline Scibaer

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Re: maunal specs question on velocity
« Reply #3 on: April 17, 2008, 01:27:48 AM »
I had it in my head that there were alot of variables, and that those could be a problem but i then wondered why they posted them in the first place.

we seem to trust the charge spec's and the brass dimentions are a given, but the fsp seems to be non critical info. ( based on we cant match all variables )

 so what do we use the fps data for ?

Offline moosie

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Re: maunal specs question on velocity
« Reply #4 on: April 17, 2008, 03:46:41 AM »
The FPS specs are there to give a "ballpark" figure for comparison to other powders and bullet combinations shown.  You can see that some are considerably faster than others and that is the what the specs are intended to show, not the specific fps of the load.
To fire an accurate shot means to not just hit the target, but to know where the target was hit before the bullet got there.

Offline Kurt L

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Re: maunal specs question on velocity
« Reply #5 on: April 17, 2008, 04:04:30 AM »
As others have said.
Example i have 3/ 30-30 guns and with 125 Speer TNT HP bullets loaded with Reloader 7
and shot over chrony they range from 2460 to 2487 to 2530 for the 3 guns.
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Offline beemanbeme

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Re: maunal specs question on velocity
« Reply #6 on: April 17, 2008, 08:04:11 AM »
The answer is no.  Even taking the same rifle and reloading the same case as carefully as you can, there will be a shot to shot variance in velocity. 
One way in which you can use the velocity figures if you have a Chrony is if you are approaching the velocity from the max load in the book and your powder charge isn't close, you might want to watch for pressure signs. 

Offline steve4102

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Re: maunal specs question on velocity
« Reply #7 on: April 17, 2008, 01:55:36 PM »

 you might want to watch for pressure signs. 

  What are some those "pressure signs" you speak of?

Offline Scibaer

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Re: maunal specs question on velocity
« Reply #8 on: April 17, 2008, 02:15:08 PM »
Ok i think i understand. so if use the data for reference only, i should then use my own chrono data for reliable fps data, right ? ( rifle specific )
now, if i get good accuracy at any given top velocity, should i back off a few fps or leave it where it at ?

Offline charles p

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Re: maunal specs question on velocity
« Reply #9 on: April 17, 2008, 03:03:21 PM »
I don't even trust the load data.  Never chronographed a load but I've had many pressure problems with published loads.  I recently tried a published 7mm-08 load that would not even fit into a case, and it was not listed as a compressed load.  Go figure.  Best to have many manuals to reference.

Offline stimpylu32

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Re: maunal specs question on velocity
« Reply #10 on: April 17, 2008, 03:09:22 PM »
steve4102

Some of the most common things people look for are flattened or pierced primers , stiff bolt extraction , bolt face impressions on the case head . These are not hard and fast rules , just some things that most use as a guideline .

Glenn

Thats perty much the case , each gun is a world all to itself , if you get the groups that you are happy with stick with them , in most cases the gun will find the sweet spot before you hit max , also loads at or near max tend to shorten case life .

Wish i could give the perfect answer but there is just not one .  ::)

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Offline steve4102

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Re: maunal specs question on velocity
« Reply #11 on: April 17, 2008, 04:52:11 PM »
steve4102

Some of the most common things people look for are flattened or pierced primers , stiff bolt extraction , bolt face impressions on the case head . These are not hard and fast rules , just some things that most use as a guideline .



  Yea, That's what I thought too until I read this from Graybeard.

  Well again sadly if you take all you know of pressure signs and all the rest of the reloaders of the world combined know about pressure signs and put it all in one bucket you won't have enough knowledge to buy a cup of coffee.

Those old wives tales of what to look for are a load of malarky and have been stated to be such these days by just about every known magazine writer in the business. I think they are finally coming around to the reality that if they keep on BS'ing folks that those signs have meaning they just might be on the losing end of a lawsuit some day.

Every test I've seen run comparing al those "pressure signs or indicators" to real world pressure data show them to be meaningless. You might see signs of high pressure even with the minimum starting charges or you might not at blue pill proof load levels. Believing you can tell what is safe in that matter is a recipe for disaster and it's time folks begun realizing it.

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #12 on: April 18, 2008, 01:13:13 AM »
I have rarely reached book velocities. When I get pressure "signs" I am well over where I should be. I develop loads for accuracy, not velocity. What good is it if you get an extra 100 - 150 fps if you can not hit what you are intending to hit? What makes the big whoop if I am running at 3250 fps when the book/s says I can get 3400 fps? If I develop a load that I think is safe and after 4-5 loadings the cases are shot, then I have been loading too hot and will develop a new load. It really upsets me when that happens. When I have the pressures where I think they belong, I get long case life and only have to full length size every 5th time or so. In some ways, I am a cheap bastard, I want my cases to last for many loadings. One way to economize reloading, is to make your cases last. If I am not getting the velocity or bullet performance I want, then it is time to get a bigger case or change bullets to get the performance I want. Do not try to turn a 223 into a 22-250  or a 7-08 into a 7mm mag, it ain't going to happen so why try?
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Offline Scibaer

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Re: maunal specs question on velocity
« Reply #13 on: April 18, 2008, 01:53:33 AM »
I first should have said Im still pretty green to handloading. now saying that i wont even try and talk about pressure signs, i have read so much either way i dont know what to think.

anyway, i'm not trying my make my rifles something they are not, but  i do want know that the loads i develop are up to where they should be velocity and performance wise along with built correctly and i wanted to be sure of how i was reading the available data.  case life is important to be, but when i squeeze off a round i want to know that i am safe, the gun is not going to get wrecked and the bullet will do its job on the game ( most of my handloads are for hunting, target shooting or plinking for me is practice for hunting )
  i dont need to run the full fps the manual says, but i dont want to run way below the potential if the load/gun can handle either. like i said the next step is a chronograph and in that light, i wanted to get some background info from guys here that have more experience then i do, to make what ive been reading a bit more clear. i appreciate the advice that i get and try to understand it and put it too good use.  there is probably not any perfect answers, but you guys have dealt with this more then i have, and if the brass gets fatigued, it should stand to reason that you will see it ( pressure signs ? ) but i have shot factory ammo and had flat primers and buldges, so i dunno at this point. but i do think the terminal verlocity is important ( mostly for accuracy and a clean kill ) . something else i want to learn is case annealing, heating the work hardening out of the brass should add some life to them.  so, i ask when i dont  know, and i find thats quite a lot, lol .
glenn

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #14 on: April 18, 2008, 07:08:41 AM »
I have limited experience with factory loads. I have mostly bought all of my components and rolled them myself. The few factory loads I have shot, seemed fairly hot. Start with fresh cases, full length sized once fired cases from other guns or neck sized cases fired in your same gun. Pick a likely bullet or two for your application. Now pick an appropriate powder or two from your reloading books. Based on the case size, powder type, availability, pressure of cartridge, etc decide on a primer. Find the OAL of your case based on your bullet selection and the chamber to determine where the bullet will touch the lands. Then depending on your application decide how far from the lands to seat your bullet. For a big game, cambering reliability dictates that your bullet have some jump to the lands. For bench rest work, you may decide to start in the lands. Once you decide where to seat your bullet, we start looking at powder weights.  When you work up a load for you gun, start with the minimums recommended. Then depending on the case capacity, make minimal jumps in powder weight. For a 22 Hornet make .1 or .2 grain jumps. For a 243, .5 grain jumps will work. Start firing your loads in the order you loaded them from lightest powder weight to the heaviest. Note group sizes and when they have shrunk to their smallest size with out increasing to the next weight in powder, you have found your load. Do not exceed recommended powder charges under any circumstances. If you can not find any thing that satisfies your accuracy goal, then start over with a different powder, bullet or primer. If you start over with any component, start low and work your way up again. Once you find an accurate load, then you can experiment with OAL to see if that helps you or hurts you. If you have tried several powder/bullet combinations and can not find anything reasonable accuracy wise, you may have a problem with bedding, bad crown, loose mounts, in other words, some thing wrong with the gun. Like I stated above, I do not worry about top velocity, because I have found that the few fps difference does not really make that much difference, not as much as you might think. 150 fps difference will probably only mean less than 50 yards in your over all point blank range. With a 223 maybe 260 yards vs 300 yards, big deal. I have covered a whole lot of ground here, so there maybe some thing that you are not clear on, if so ask, i will try to answer the best I can.

As far as case annealing Hornady makes a kit for annealing cases, that I found very easy to use. It has three sizes of case "spinners", a bottle of heat sensitive liquid and instructions. Annealing is for the case mouth and shoulder area only. Do not think you can stretch primer pockets and shrink them back down. It will not help with head separations, both can be caused by over pressure situations. If you are running high pressures, you will be enlarging primer pockets and stretching the case so much that annealing will not be needed, you will ruin the case before any annealing will be needed. If you continually run high pressures, you will not need to anneal. There are lots of folks that do this, they never anneal, because there is no need for it. I anneal some where around 8 loadings or so, depending on what gun it is and how much the brass is being worked in the neck/shoulder area.

Some guys like to brag about how fast they can push such and such bullet. I would rather brag about group sizes. The two do not go hand in hand, some times they do, but not always. If I have to run on the ragged edge to get out the accuracy, I switch loads, I just do not like to run that high, you not only shorten the case life considerable, you run the risk of damage to you gun or worse your self. I have been down that road of getting as much as possible out of a cartridge. I have had blown primers, primers that fell out of the pockets, split case necks, the whole gamete.  I have found that I did not gain as much as I thought, and I never knew how it was going to act. 1 shot would be OK, then a blown primer the next. I just never knew what to expect when riding that fine line. I found this out shooting a 222 Remington for years. I ended up switching to a bullet that would blow up way down to 2000 fps. I was able to hit black birds out to 250 yards. It did every thing I needed and I was running in the 2900 fps area with 50 grain bullets. If you know of someone that has been reloading for a long time and really enjoys the hobby, I think you find that they are not running on the ragged edge either. It comes with experience, you just find out that that few extra fps is not worth the problems it causes. If you really need to get more distance (velocity) out of your gun, then you really need to think about getting another gun that will do what you want. If what you want is out of reason for the biggest baddest cartridge you can get, then you are expecting too much out any gun. Be reasonable. Be safe. just my 2 cents. Good Luck and Good Shooting
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Offline Scibaer

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Re: maunal specs question on velocity
« Reply #15 on: April 18, 2008, 08:03:13 AM »
wow, thats alot of info there, let me take the time to read it and digest it all.
thanks for taking the time to type that all out.  in any event i did skim over it once and i appreciate your advice.
there is just so much ( mostly experience ) to reloading and the testing, measuring and figuring out how it all works and what works or dont, i think im adicted to it all ready.
i am working up 80 rounds for my .243 with 5 different bullets weights and powders and cant wait to run them thru a chrony to see whats what, lol ..
 thanks again, and im sure i'll have more questions as the more i read the less i know,
glenn

Offline beemanbeme

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Re: maunal specs question on velocity
« Reply #16 on: April 18, 2008, 08:50:36 AM »
I agree with a good deal of what Laotto sez. Especially that you should load for accuracy and not for velocity. Especially velocity in and of itself.  But you must have a usable velocity.  Once you have reached @ 75% of what the book sez is max and find that your rifle will sustain it, you should start looking for your best accuracy.  Folks that maintain that the extra 100fps will give them flatter trajectories and greater kill potentials are really just stroking their egos.

I don't agree that empirical pressure signs are useless though.  They've served quite a few generations of careful reloaders and it wasn't too long ago that these were the methods used by all but the very largest bullet companies to determine maximum loads.  It was Speer, I believe, that used this empirical methodology long after pressure testing equipment became readidly available on the premise that it was the way reloaders did it.  

A flattened primer and an engraved case head or a cupped firing pin strike may only mean a bit of head space or an enlarged firing pin hole. A resistant bolt lift may mean a grungy chamber.  But when they come together, the smart reloader takes his foot off the throttle.  If, after just a couple or three loadings,he's getting sloppy primer pockets or losing cases, he's running very hot.  Even if the load is within boundries according to the load book.  In his rifle, that load is hot.  And that includes magnums.

Its been said that by the time any of the pressure signs appear, the pressure has far exceeded safe limits by a major amount. Having no pressure testing equipment, I don't know. Why do they have a starting load and a max load?  Why not just post a load for each calibre? Why have these signs and how to use them been published in every load book I have ever read?  And that goes back a ways. I do know they have worked for me.    

One of the tricks a starting out reloader can do is buy him a box of factory ammo for his rifle with a like weight bullet to what he will be loading.  And shoot it.  Measure the fired cases acrost the web and record those.  Use the largest expansion plus a bit as your maximum expansion for your reloads depending on what you're reloading.

IMO, a Chrony is one of the cheapest $100 you can spend on reloading.  Used correctly, it will give your so much more information other than how fast your bullet is going.   :D

Offline steve4102

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Re: maunal specs question on velocity
« Reply #17 on: April 18, 2008, 12:26:08 PM »
Do not exceed recommended powder charges under any circumstances.

  OK, but what if the max recommended powder charge is way over pressure in my rifle?  According members here, there is absolutely no way for me to tell that the max "recommended" load is way over pressure in my rifle.  If I cannot tell what is a "hot" load in my rifle, then what is the point of starting low and working up as it pertains to pressure.  Seems to me that the only reason to start low and work up would for accuracy only as pressures can not be recognized.  When and if I find an accurate load and I am at or under published max I am good to go regardless of any obsolete signs of pressure I might have. Correct?

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #18 on: April 19, 2008, 02:02:07 AM »
"When and if I find an accurate load and I am at or under published max I am good to go regardless of any obsolete signs of pressure I might have. Correct?"

Wrong. These "obsolete" pressure signs do not tell you when they are safe. They tell you when you are over safe max pressures. Unfortunately, it takes some experience to go along with the "signs" to tell when you have exceeded the max pressure for your gun. I have said not to exceed published max powder charges. For one thing, you can not go by one reloading manual. You should have several up to date books and compare their loading data. Just because one book says 35 grains of XXX powder will be safe, does not mean that it will be safe in your gun, under your circumstances. Work your way up incrementally from a low pressure load. Check for accuracy, but also note if you are starting to get flattened primers, cratered primers, etc along the way. If you are getting rounded corners on your primers and then as you step up the powder charge, it starts to flatten (like it should), keep an eye on it. If it is a steady progression, then you can be pretty sure the pressures are increasing and the "signs" are accurate. When you shoot an unknown load and you get a cratered primer or it is flattened out, you do not know if it because of it being too hot or if there is another problem, like a larger than needed firing pin hole, over sized primer pocket, you just do not know. If you work your loads up slowly, you will get a feel for a over pressure situation. You get this through knowing where you are with the published data and the way things look as you progress through the powder weights. There is no hard and fast rule that says "I am now at the maximum pressure". I do not have pressure equipment at my disposal. As I have stated earlier, I have done about every thing you can to a case/primer, through my own inexperience or just plain stupidity. If you think you have a safe load, but find that your primer pockets are stretched to the point of primers falling out after reloading 5 times, you are exceeding max safe pressures, I do not care, what the signs are. Like I said it takes experience along with the "signs". I have been pushing not to exceed max pressures and if you need a bigger cartridge, then get it and do not turn your gun into something it is not, but on the other hand you have to get some performance out of it. A 100-200 fps difference is not going to make a whole lot of difference, but 500 fps will. If you are supposed to get 3500 fps out of a gun and you find a safe, accurate load at 3300 fps, be happy, it will not make as much difference as you might think. However, if you are only getting 3000 fps, now we are starting to talk a real performance difference you can tell very easily. I would try to work up another load that will get me closer to the potential of the cartridge, with out exceeding safe pressures. Good Luck and Good Shooting
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Offline Scibaer

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Re: maunal specs question on velocity
« Reply #19 on: April 19, 2008, 03:45:07 AM »
Let me ask the a really basic question... pressure signs are supposed to be the result of the brass being compressed or to much force excerted on it by the burning of the charge when the charge is of too high a pressure ? do i have that correct ?

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #20 on: April 19, 2008, 04:57:07 AM »
Correct. Brass stretches every time it is fired, even a medium pressure charge will stretch it. The case will expand to fill the chamber, unless it is very low pressure. If the chamber is large in comparison to the case, it will stretch so much that it can not spring back to it's original shape/size. The key is not to stretch it to the point that it does not have any spring back (brass memory). Head space causes it to stretch in the area just above the web (to grow in length), that is unavoidable. When you neck size, you minimize this stretch because it is already stretched to fill this area. The next time it is fired, it will again try to fill the area between the shoulder and the head, but this time it does not stretch very far and springs back just a little. The neck stretches so that a bullet will slide into it with out any resistance. We must re-size the neck every time if the chamber and case neck are dimensioned to standard. The case body stretches to fill the chamber and springs back a little. A high pressure round will stretch it and leave a "sticky" case because it does not spring back very much. Of course a sticky case may be caused by other factors as well, like camber condition, presence of lubricant, etc. The head will stretch very little if the pressures are not excessive. If they are, the head will grow in diameter and make the primer pockets over size. When the head stretches at peak pressure, it looses it's grip on the prime + the pressure coming through the primer hole, making it easier to drive the primer back, flattening, cratering, or piercing it. A lower pressure round will not lose it's grip as easily and the pressure coming through the primer hole is not as great. The high pressure round will stretch it to the point it will not spring back to it's original size. In this area, it very important to spring back t it's original size or not have any stretch at all.

With out pressure measuring equipment, you are guessing. Hopefully you guess correctly. There are so many factors that cause case/primer problems that it is very difficult to determine if you are over pressure or have other issues. That is why you have to know where you are at with your loads and keep an eye out for pressure signs along the way. To just look at a case and say you are over pressure or safe is not a very good way of telling. Developing a load is a journey and you must "smell the roses" along the way, pay attention and use some common sense. Reloading can be a very satisfying experience or it can be a nightmare, it is up to you.
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Offline Scibaer

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Re: maunal specs question on velocity
« Reply #21 on: April 19, 2008, 05:23:39 AM »
the physical attributes you describe are understandable. it seems to me that's the way it should work.  it also makes sense to me that the only way you can "see" pressure signs is if you know your rifle and the  load you are using really well. say, you load X powder at X grains with X brass and primers under X bullet enough times to know how it shoots and the brass looks. then you could bump up the charge and "see' excessive pressure. assuming you start with a load that does not tax the brass in the first place.
now, does the brass have a specific hardness or density to it from the manufacturer, or is there a variation in the softness/hardness ? its sounds reasonable to me that softer brass would deform more then harder brass, showing ( real or false ) pressure signs..     case in point, my buddy has  NEF .243 and shoots nothing but factory winchester 100 gr. sp out of it. he gave me a bunch of once fired brass after he zeroed his scope at a day of shooting at the range.  some of it had flattened primers, others didnt, some was black at the mouth or shoulder while some of it looked perfectly clean.. there was a variation in the fired brass, with some showing "pressure signs" so was some of that brass softer then the others ?
glenn

Offline steve4102

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Re: maunal specs question on velocity
« Reply #22 on: April 19, 2008, 08:27:48 AM »
  Thanks Laotto, I appreciate your help.  Only problem is I am more confused now than ever.

  On one hand I have you telling me that there are pressure signs that I should be looking for and know how to read them.

Quote
These "obsolete" pressure signs do not tell you when they are safe. They tell you when you are over safe max pressures. Unfortunately, it takes some experience to go along with the "signs" to tell when you have exceeded the max pressure for your gun.  Check for accuracy, but also note if you are starting to get flattened primers, cratered primers, etc along the way. If you are getting rounded corners on your primers and then as you step up the powder charge, it starts to flatten (like it should), keep an eye on it. If it is a steady progression, then you can be pretty sure the pressures are increasing and the "signs" are accurate. If you work your loads up slowly, you will get a feel for a over pressure situation. You get this through knowing where you are with the published data and the way things look as you progress through the powder weights.  If you think you have a safe load, but find that your primer pockets are stretched to the point of primers falling out after reloading 5 times, you are exceeding max safe pressures, I do not care, what the signs are. 

  On the other hand I have Graybeard telling me that these pressure signs you speak of are completely worthless and all of them put together ain't worth a cup of coffee.

  You both can't be right.  Either there are pressure signs a handloader can feel or see or there isn't.  Which is it?

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #23 on: April 19, 2008, 11:41:01 AM »
Well we can get more technical here. There is what is called an elastic limit. Below the elastic limit is where a metal stretches and returns to it's original shape. Above the elastic limit and the metal will not return to it's original shape. In a case there are different forces at work, depending on where you are in the case and where you are in relation to the chamber. The case is most certainly going to go above the elastic limit in the case head to shoulder area. Same for the neck. It will go above the elastic limit and grow in diameter until the chamber walls stop it. Then we shrink it back down to hold another bullet. After a while this work hardens the neck. The brass becomes more brittle raising the elastic limit, but lowering the yield point. When the yield point gets too low, it will fracture (split case mouth). We do not want the brass to exceed the elastic limit across the head. When we do, that is when primer pockets start to loosen. Brass has different limits from lot to lot and from manufacturer to manufacture. Some brass costs considerably more than others. One reason you pay more... because they control the brass properties more. When you do that you get more consistent properties from lot to lot and with in the same lot. So a load that is safe in one case may not be in another. All the more reason not to push the ragged edge in pressure. Develop a new load if switching brands of brass, do not mix brass brands, ect. It is not all about case capacity. You may find that from lot to lot, within the same manufacturer, there is different properties too.

Now comes what Graybeard has said. That all the signs are not worth a dime basically. In a way he is right. There are so many variables involved, some of which I have mentioned, but not all; that a "sign" does not mean a hill of beans. He is correct of course. What I am trying to explain...I have no way of measuring actual pressures. All I got are signs. Graybeard has mentioned using a chronograph to determine when pressure limits are reached. Increase your powder load until you have reached the same maximum velocity in the book. And as long as you do not exceed the book powder charge and do not blow a primer you are good to go. I hope I have interpreted this correctly. It is certainly a method of determining a max load. I started long before there were chronographs widely and cheaply available. So I developed this way because it was all I had. Maybe I should change with the times, but I think my method is just as reliable as that. I still think you will have a problem determining maximum safe loads. There is no good way of telling, with out measuring many loads with special equipment. I was just trying to give a way to develop a safe load, that will give satisfactory results. It is not all a sign game. It is knowing where you are at in relation to book values and watching the "signs" as you increase the powder charge. If you have a primer that is rounded at the edge with a nice looking primer dent and when you increase it by .5 grains and then all of a sudden you have a pierced primer, some thing happened. Have you went over the pressure limit, have you got soft brass, have you got a bad firing pin? Knowing how you got there and watching the signs on the way are how you determine where to look, spelled experience. I mean if you are approaching the upper limit of the powder charge and you have progressively gotten flatter and flatter primers, then you blow one - you have far exceeded safe pressures, period, I do not care where you are in velocity. If you have a blown primer out of no where, then you may have a problem some where else. Solving these problems is where experience comes in, just pay it safe until you get experience and after as well. You need to be even more cautious until you know what you are doing. Remember if you have reached the point of pressure signs, you have a problem, be it over pressure stemming from an over load, bad cases, bad primers, soft primers, bad powder, improperly sized cases or a problem with your gun. Just remember a sign in it self tells you nothing, I whole heartily agree with Graybeard on that point. You are an idiot if you think you can pick up a case, look at it and say you can put more powder in to get it up to the speed you want or you have exceeded the pressure limit of the case with out knowing how you got there. If you develop an accurate load on the way to find the max load, and you have not reached the max point, be happy. As long as it has acceptable velocity. Who really cares if you never found your safe maximum velocity, you are using a safe load and that is what really counts. If you can not get to where you want to be, then start over with a different component or get a different gun shooting a bigger case.
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Offline steve4102

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Re: maunal specs question on velocity
« Reply #24 on: April 19, 2008, 06:05:50 PM »
Thanks again LaOtto, It is clear to me that you believe you are able to read your brass, rifle, recoil etc to indicate when your load and rifle have reached high pressure.   The pressure signs you speak of like blown primer, flat primer, loose primer pocket, recoil, excess velocity, sticky bolt lift etc. etc. are all well known indicators of high pressure, or at least I thought they were.  According to Graybeard all these signs are worthless and meaningless.  Use them  together or use them individually it matters not, they are nothing more than "Old Wives Tales". 

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Well again sadly if you take all you know of pressure signs and all the rest of the reloaders of the world combined know about pressure signs and put it all in one bucket you won't have enough knowledge to buy a cup of coffee.

Those old wives tales of what to look for are a load of malarky and have been stated to be such these days by just about every known magazine writer in the business. I think they are finally coming around to the reality that if they keep on BS'ing folks that those signs have meaning they just might be on the losing end of a lawsuit some day.

Every test I've seen run comparing al those "pressure signs or indicators" to real world pressure data show them to be meaningless. You might see signs of high pressure even with the minimum starting charges or you might not at blue pill proof load levels. Believing you can tell what is safe in that matter is a recipe for disaster and it's time folks begun realizing it.

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #25 on: April 20, 2008, 12:51:54 AM »
First off I am not saying Graybeard is full of it. What I am saying is pressure signs is what I have, so I do the best I can with it. The more information you can gather the better. Use a chronograph if you have one. Use it along with what I have been saying here. Gather as much information as you can. Be aware, examine each case during your load development stage. Reread what beemanbeme had to say. I think he has a good handle on it. Remember when you get the signs, you have more than likely crossed the maximum pressure thresh hold unless you have another problem. You will not know unless you have developed your load. Your goal is not to get them. Do not keep increasing your powder levels until you do get them. If you do then you have to back off or develop another load. Hopefully you will get an accurate load before ever getting to the maximum pressure limit and still have adequate velocity. If you do get high pressure signs, then back off. The goal is to get an accurate load before you reach the maximum pressure point. Also this is definitely not an exact thing, I believe that is what Graybeard was talking about. There are so many variables involved. There are many reloaders that load above the max pressure and do not know it or do not care. They think they are doing OK, but after 5 loadings they have to replace the brass. That is also an indication they are loading hot. That is a sign too even though they seemingly get no other indicators. Some reloaders ignore this and load up the new brass to the same specs as before and start the cycle all over only to replace the brass after 4-5 loadings, again. Bench rest shooters are extremely picky about their brass. They usually buy the best quality brass they can. They spend hours prepping and sorting it. Do you think they are going to go out and run high pressures to get as much velocity as they can? They want their brass to last a looong time. In many cases they have a small lot they work with sometimes as small as 25 cases. They reload these carefully prepped and sorted cases over and over. They want as much "sameness" as possible from case to case. They want the bolt to lift easily so they do not knock the gun off the target each time they load the gun and have to settle it back on target. Yet they also want as much velocity as possible so that the wind does not have as much effect on their bullet. Sort of what a varmint hunter should be striving for. Big game hunters do not have to be as picky, but their loads should be very reliable. Over stressing cases is not a way of making reliable loads, you never know when a case is going to fail and blow gasses back in your face, lock up the action or separate a case head so you can not load another round. One more thought...Just because the SAAMI specs say XXXXX cup is the maximum pressure does not mean you have to run it that hot, you need to stay below that.
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Offline Graybeard

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Re: maunal specs question on velocity
« Reply #26 on: April 20, 2008, 02:55:12 AM »
The problem with all these "pressure signs or indicators" is that you still have no way to know what it was that caused any one of them to occur. Thus they really are pretty meaningless.

Folks speak of flattened primers as a pressure sign but there are many reasons other than pressures being too high to cause primers to flatten. It has been proven time and again by folks with pressure measuring equipment that even at 100,000 PSI primers may not flatten. It has also been shown they they might flatten at 30,000 PSI. So looking at the primers really tells you pretty much nothing.

Folks like to talk about measuring the expansion ring but not one in a thousand really know how to do it correctly and even if they do it too is about as meaningless as any other. It is a comparative tool only and you must first have a baseline to compare to using that brass in that rifle. Not one in a million do.

Bolt lift is often spoken of as an indicator of pressure. Well yeah MAYBE but then maybe not. At best if the bolt is locked down so you have to use your boot to open it that might tell you pressure was too high but how much too high? What do you do about it? Just drop back a grain or so? Nope cuz you don't know if the pressure exceeded 150,000 psi or if the real problem was excessive headspace, soft brass or anyone of a dozen other possible reasons.

I could go on but each and every sign folks use has been proven over and over again to be totally unreliable individually and taken as a set to indicate what is and isn't safe.

If you load a round and it locks the bolt so you have to take a hammer and open it and the case is welded to the bolt and split wide open that's a darn good indication you over did it for sure. But by how much? What do you do about it to fix the problem? The "indicators" don't tell you.

If you think you can "read pressure indicators" and tell when your loads are safe and when they become unsafe then please advise me if you're gonna be anywhere near me so I can avoid being there when you blow up your gun.

There is not one single or multiple pressure indicator you can use to tell the difference between a safe 50,000 psi and a very unsafe 150,000 psi in a modern bolt action rifle. The problem is that magazine writers told us for 40 years there were and now even tho all of the major name writers have come out and admitted they were wrong all those years and that you can't do it that way folks refuse to listen now and just keep on believing the old stories from the days before pressure measuring equipment was commonly available and in use by all reloading manual makers.


Bill aka the Graybeard
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I am not a lawyer and do not give legal advice.

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Offline steve4102

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Re: maunal specs question on velocity
« Reply #27 on: April 20, 2008, 03:12:52 AM »
  Well, there you have it LaOtto,  You and I  are not only completely out of touch with reality if we think we can read our brass, rifle and velocity, We are dangerous and unsafe as well.


 
Quote
If you think you can "read pressure indicators" and tell when your loads are safe and when they become unsafe then please advise me if you're gonna be anywhere near me so I can avoid being there when you blow up your gun.

There is not one single or multiple pressure indicator you can use to tell the difference between a safe 50,000 psi and a very unsafe 150,000 psi in a modern bolt action rifle. The problem is that magazine writers told us for 40 years there were and now even tho all of the major name writers have come out and admitted they were wrong all those years and that you can't do it that way folks refuse to listen now and just keep on believing the old stories from the days before pressure measuring equipment was commonly available and in use by all reloading manual makers.

Offline Scibaer

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Re: maunal specs question on velocity
« Reply #28 on: April 20, 2008, 03:32:30 AM »
GrayBeard,
 let me ask you, as a handloader and shooter, i am sure that you have gotten one or more of these pressure signs with your brass at one time  or another.
 so, what have/ did you do, keep loading with the receipt you were using ? or back off the powder charge, or some of aspect of the receipt ? or something all together ?
 the reason i ask is, short of actual test equipment, these signs ( or at least problem indicators ) is all we have, and if you choose to ignore them, what do we have ?
glenn

Offline LaOtto222

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Re: maunal specs question on velocity
« Reply #29 on: April 20, 2008, 04:35:39 AM »
I think I have been misunderstood here. I believe every thing Graybeard has been saying here. I have not once disputed his statements. He has lots of experience that I respect. He has been going down the safe road, and telling us that there are just too many factors involved to know with out doing actual measurement of pressure. I have simply been trying to give people a way to work with loading data. I am not getting my point across very well. I have been telling you that there are lots of factors to be figured in, same as Graybeard. I have been saying to error on the safe side. I have been saying that I do not have pressure equipment, so I use the indicators, but I also said that you have to know what you are doing and even then you are guessing. Hopefully through some common sense and knowing where you have been you can develop a safe load. Things can go wrong. I do not want to scare anyone from reloading, but you do have to use caution. You need to follow reliable reloading data and use as much of it as possible. Those guys did a lot of research and had the equipment do do it right. The original question was do you get published velocities. I rarely hit published velocities. This is because before I get there I usually find an acceptable, accurate load or I start getting signs that some thing is wrong. What is wrong is open for debate, but when you have a blown primer, some thing is definitely wrong. It does not matter if you are well below published data limits, there is some thing wrong and you better find out what it is. I resized cases down from 223 to 221 FireBall. Like an idiot, I did not check out neck thickness. It was too thick to release the bullet. Even though it was a starting load, on the first shot, the primer fell out of the pocket. Duh, even though it should have been a low pressure round, what I did was make it a bomb. Needless to say the rest of that lot was pulled down and case necks turned. I do not think that pursuing this any more on my part will be productive. I still want to state that Graybeard is correct, I was simply trying to help you understand how to develop a good safe load. Because Graybeard has more experience on this board, he knows better, and I was naive enough to think I could help you to develop a good, safe load with out pressure equipment.
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