Author Topic: OVERALL LENGHT !  (Read 725 times)

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Offline steelhead51

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OVERALL LENGHT !
« on: July 27, 2010, 03:15:13 PM »
What do they mean by the overall lenght , in lee reloaders manual and sheet supplied with dies say for instance 30-30 win. they give a oval loaded catrige lenght useing a flat point bullet, but what about a boat tail ballistic tip, seated , it's a lot longer than what there saying, a sirerea 125 gr. soft point is shorter than the BTBT , but still longer than  what they say is over all bullet length should be. I've been reloading for this 30-30 for some time now and never gave it much thought are they refering to a lever action, the gun I load for is single shot H&R and T/C contender. I can see cartrige length being issue in revolver but not in single shot rifle or pistol. Help me out on this issue please

Offline bobg

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Re: OVERALL LENGHT !
« Reply #1 on: July 27, 2010, 03:53:57 PM »
  I don't pay much attention to the manual AOL. I seat the bullet just short of the rifleing. It is to long to fit the magazine on my 22-250 but it is strictly a varmint rifle so i load it single shot. My deer rifle i load to fit the magazine. This doesn't really answer your question but it is what i do.

Offline steelhead51

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Re: OVERALL LENGHT !
« Reply #2 on: July 27, 2010, 05:02:40 PM »
Thats kinda the way I think if it fits it's good enough! Iam not getting any bad pressure signs or anything. I too seat the bullets so they just touch rifeling and action closes and locks up.

Offline drdougrx

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Re: OVERALL LENGHT !
« Reply #3 on: July 27, 2010, 05:06:36 PM »
Bobg is right.  The OAL is subjective.  I just sold a Rem700 in 30-06 and could easily load any cartridge to 3.45".  My new SAKO only lets me load them to 3.3"  The nosler manual gives you an OAL for their cartridges and then tells you that the most accurate loads are a bit longer....so just off the rifleing and functions in the magazine...good advice as any I guess.  

You COULD load to min specs and then increase your length by .05 increments until the cartridge is too long and see if that effects accuracy.
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Offline necchi

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Re: OVERALL LENGHT !
« Reply #4 on: July 27, 2010, 05:53:44 PM »
I too seat the bullets so they just touch rifeling and action closes and locks up.
I would urge caution here, different bullets have a different ogive or curve to the side of the bullet. Each type is going to seat at a different length when they "just touch rifling".
I too have Handi's, and all mine have a really long throat. With the 223 I can't touch the rifling,,the bullet leaves the case.
With the 7-08 and Barnes bullets,,I have the best accuracy with the bullet .100-.120 off the lands.

So just crammin the bullet into the rifling isn't always the best bet,,and it sounds like you know that if it's jammed too much you can reach dangerous pressures.

be carefull man  ;)
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Offline southernutah

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Re: OVERALL LENGHT !
« Reply #5 on: July 27, 2010, 06:10:04 PM »
the posted OAL is a sammi spec set for every cartridge so it will fit in stand barrels and the magizine. to long and it may cause over pressure in some firearms and not fit in the magizine.  error on safty and not hearsay.

Offline Dezynco

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Re: OVERALL LENGHT !
« Reply #6 on: July 27, 2010, 07:26:11 PM »
The beauty of a single shot is that you can monkey with OAL.  The Cartridge Overall Length is a "standard" that will indicate a good starting point that should be functional in any firearm that is chambered for that caliber.  With single shot firearms, you can seat the bullet to get the best accuracy.  When you must stuff the ammo into a magazine, the ammo must be able to cycle through the action (bolt, lever, or semiauto).  

Be careful when seating bullets out to be close to the rifling, you an get into some pressure issues there. I usually seat out as far as possible without cramming the bullet into the rifling for hole punching (if it will still seat in the case deep enough to stay put), but seat the bullets a little deeper for cartridges that might go in my pocket for hunting.

Offline shot1

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Re: OVERALL LENGHT !
« Reply #7 on: July 28, 2010, 03:59:32 AM »
Different bullets like different jump lengths into the rifling. Here is how to find out the max OAL to your rifling. Take a case and FL size it. Cut a line from the mouth of the case down to the start of the shoulder on one wide of the neck. Clean up the burrs. Before each use run the case into your size die to re-size the neck or just pinch the neck together a little so it will hold a bullet snug. Take the bullet you want to use and just start it into the case with your fingers. Place the case into your chamber and close the action. Carefully remove the case. The bullet will have been pushed back into the case when the o-give hit the lands of the rifling. This is your to the lands measurement. It is best to use one of the tools that measures to the o-give to get your correct OAL because not all bullets in the same box will have the same nose length but they will have the same o-give length. The best place that I have found to start with for an OAL is 10 thousands off the lands. I have found that many bullets shoot very well there. Work up your most accurate load with the 10 thousand off setting and then you can play with your OAL to see if you can improve accuracy. Work in 5 thousands at a time. You will discover that most bullets have a window between 5 and 10 thousands that they shoot the same.

You can pull the bullet from this case with your fingers and load it up and shoot it.

Write down your measurements and the bullets used. You will not be able to remember them a few months down the road.

Each different make or weight bullet will have a different OAL measurement so do the above with every different bullet.

Offline steelhead51

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Re: OVERALL LENGHT !
« Reply #8 on: July 28, 2010, 08:15:38 AM »
THANKS GUYS , I think you've answered the question for me , I'am always measureing and checking lenghts and weights [ verry carefull ] I'am not a speed loader. just easy going verry cautious loader.

Offline GH1

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Re: OVERALL LENGHT !
« Reply #9 on: July 28, 2010, 12:34:29 PM »
Correct OAl is critical in lever guns and semi autos, less so in revolvers or single shots.  At least from the standpoint of the ability to function.  However, too short of an overall length can indicate a bullet being seated too deeply, which can cause dangerous pressure spikes.
But like you say, a ballistic tip is going to have a greater OAL than a flat point.
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Offline DDZ

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Re: OVERALL LENGHT !
« Reply #10 on: July 28, 2010, 12:58:03 PM »
Different bullets like different jump lengths into the rifling. Here is how to find out the max OAL to your rifling. Take a case and FL size it. Cut a line from the mouth of the case down to the start of the shoulder on one wide of the neck. Clean up the burrs. Before each use run the case into your size die to re-size the neck or just pinch the neck together a little so it will hold a bullet snug. Take the bullet you want to use and just start it into the case with your fingers. Place the case into your chamber and close the action. Carefully remove the case. The bullet will have been pushed back into the case when the o-give hit the lands of the rifling. This is your to the lands measurement. It is best to use one of the tools that measures to the o-give to get your correct OAL because not all bullets in the same box will have the same nose length but they will have the same o-give length. The best place that I have found to start with for an OAL is 10 thousands off the lands. I have found that many bullets shoot very well there. Work up your most accurate load with the 10 thousand off setting and then you can play with your OAL to see if you can improve accuracy. Work in 5 thousands at a time. You will discover that most bullets have a window between 5 and 10 thousands that they shoot the same.

You can pull the bullet from this case with your fingers and load it up and shoot it.

Write down your measurements and the bullets used. You will not be able to remember them a few months down the road.

Each different make or weight bullet will have a different OAL measurement so do the above with every different bullet.


This method has always worked well for me. Specialty tools do work better, but if you use this method, and do it a few times to verify your distance to lands, it works.

I was one that used to think I could remember measurements like OAL for a certain bullet, but seldom ever could. Over the years I have forced myself to do better record keeping. Also I would load certain loads thinking I could remember the powder charge I used. If I didn't get back to the loading bench for a couple of weeks, the memory of the powder charge was gone. So I have become much more efficient at record keeping. After I reached 50 years old, it seemed like I have to write down everything, if I want to recall something.  Not just at the loading bench. 
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Offline Sweetwater

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Re: OVERALL LENGHT !
« Reply #11 on: July 28, 2010, 01:39:11 PM »
My working rifle is a long throated mil-surp 8x57 sporterized. I couldn't reach the rifling with an extension! I found some 200gr spitzers (after years of shooting 150gr and 175gr) and they would just reach the rifling, with very little left in the neck! Even 220gr Boattails would not reach, so "just off the rifling has been a real non-issue for me. All my other rifles have had mag limitations that were the limiting factor.

The manuals are great guides, your gun is your law. Up to you to make them fit proper. Have fun, stay safe!
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Offline shot1

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Re: OVERALL LENGHT !
« Reply #12 on: July 29, 2010, 04:03:08 AM »
Sweetwater: I have found a great accuracy enhancer for those old Military rifles that have throats a mile long. Use a Lee Factory Crimp Die. It will work with any bullet because it makes it's own crimp groove. From my testing with many military rifles the crimp die use really makes a round more accurate. The crimp on the bullet retards the bullet leaving the case for that nano-second to allow the pressure to build and get a good burn on the powder before it moves much like the bullet hitting the lands and being slowed for a nano-second. Just my theory. All I know for sure is that the Lee Factory Crimp Die improves accuracy in the long throat rifles. One other tip is to leave your case 5 thousands longer than the trim to length. This gives you enough case to get a good crimp on. When you trim the case down to the trim to length sometimes you don't really get a bite on much case when crimping. 

Offline Win 1917

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Re: OVERALL LENGHT !
« Reply #13 on: July 29, 2010, 04:04:36 AM »
Quote
Be careful when seating bullets out to be close to the rifling, you an get into some pressure issues there.

+1 +1 +1, More and more I'm feeling that seating to the lands is over-hyped. For benchrest shooters and that sort of thing where the entire set-up from action to bullet is very tightly controlled it makes sense. But for typical hunting guns and applications I think many times people would actually get better accuracy and an increased margin of safety by seating them a back a little bit (.010 is plenty).

For determining seating depth I'm going back to the old method of smoking bullets. It takes a little longer but the thing of it is I can see exactly how much contact there is with lands.  

Offline Dill45

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Re: OVERALL LENGHT !
« Reply #14 on: July 29, 2010, 11:42:53 AM »
Be careful seating bullets to deep in straight wall cartridges as well.  The deeper you seat the bullet, the less case volume you have, which will increase pressure.  If you're running a max load, it will be over pressure if you're deeper than the COAL is listed.

The smaller the case, the more profound the  effect is.  Most reloading manuals have warnings starting at about the .38's.  Small changes in the COAL for a 9mm will increase the pressure more dramatically than a 45-70.

Offline smong2000

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Re: OVERALL LENGHT !
« Reply #15 on: August 02, 2010, 04:35:51 PM »
+1+1+1 Be careful on OAL,  I learned the hard way not to seat too long ($273 repair  :'() but it could have been much worst.  If you want to touch the rifling, start at the low end and work your load up carefully and check again with every lot of bullets.  The spike happens very quickly - for me within 1 grain I went from no pressure signs to a damaged cam in my bolt and split casing.
 Even if you don't get over pressure, leaving a bullet stuck in the barrel and dumping a load of powder in the action kind of ruins your day. (I'm a slow learner, and changing vintages of the same part # bullet can result in different ogives with the same OAL).   ;)

Offline shot1

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Re: OVERALL LENGHT !
« Reply #16 on: August 03, 2010, 03:51:30 AM »
 Even if you don't get over pressure, leaving a bullet stuck in the barrel and dumping a load of powder in the action kind of ruins your day. (I'm a slow learner, and changing vintages of the same part # bullet can result in different ogives with the same OAL).   ;)
[/quote]

True, True, True 1+ 1+ 1+  I had this very thing happen on a hunting trip. I was loading the bullet to be just 2 thousands off the lands for a 7 mm Rem Mag and man did it put them in one hole at 100 yards. Before the hunting trip that I was going on 300 miles from home I bought a new box of bullets and loaded them up without checking them to see if they were the same as the other box. I went hunting the first morning and when I got into my tree stand I loaded up the rifle and waited for day light. I saw nothing for 3 hours and I could not hold those two cups of coffee I had for breakfast anymore and decided to go to my truck to take care of business and get something to eat. When I tried to unload my rifle to get down out of the stand the case came out but the bullet had stuck in the barrel and the powder dumped all down into the action. I did not have a cleaning kit in my truck so I had to drive 30 miles back to where I was staying to get my cleaning kit and clean up the rifle and poke the bullet out of the barrel. I then went to a friends house and borrowed his loading room for a while and seated the bullets a little deeper in my ammo. Then I drove back the 30 miles to hunt the evening. Those bullets had the same o-give length from the base to o-give but the nose of the bullet was a little longer and I was measuring the OAL from the base of the case to the nose of the bullet. I got me a comparator that fits on my dial calipers and now measure OAL from the o-give instead of the bullet tip which is really precise. You live and learn.