brass interchangeability

[clodbuster]

I don't really know if that's a word but here's the question.  Can brass of the same caliber and equal weight, fired once from the same gun and going back into that gun be safely loaded with equal charges of one powder.  I have different brands of brass that weigh the same-308 Win in Winchester nickel plated and R-P regular brass both weigh 155 +/- 2 grains.  My load is with H4895 and not at max with 150 gr Hornady SP bullets.  Same charge OK?  Have FC brass at 170 gr and Win regular brass at 165gr.

[jhalcott]

 IDEALLY you should work up loads with different components separately for best accuracy and safety. Even different lot #'s CAN cause problems. I am guessing that the brass is once fired FACTORY issue. MY Hornady book shows about 1 grain difference in MAX loads with IMR and H 4895 powders. They are also using Fed210 primers! YOUR brass is about 17 grains different in weight,are the cases all the same length! Where is the extra weight coming from? The thickness of the cases will make a difference in chamber pressure! I have no idea how much. ALWAYS START LOW AND WORK UP ! My book says 38.7 to start and 41.8 MAX. That is a NARROW loading range.IMR 4064 shows 39.7 start and 44.9 MAX . Win 748 (a good powder in the .308) starts at41.8 and MAX is 48.4. You can load all your brass with a starting load but separate it by brand and work up carefully. Remember safety first, you don't want to blow your gun OR your self up!

[beemanbeme]

The short answer is yes.  Say if you were loading winchester brass for a 30-06 and came into a bunch of GI (milsup) brass, using the same load in the GI brass may give you some introductory pressure signs that would mandate a grain or two reduction in powder but you ain't gonna be standing there with smoking shards of steel sticking in your head.  If anyone can document a rifle blowing up from a change in brass, I'd like to hear it.  (key word, DOCUMENT, forget about the "my buddy knows a guy whose uncle's bro in law, etc,etc stories)
Our hobby requires a degree of caution and considerable common sense but we don't have to hide under the bed every time we change primer brands.  One hint from a old but not very bold reloader: It's pretty pointless to try to motor you rifle at top end. The little extra velocity you gain cost considerable in barrel life and equipment stress.  while operating a couple of grains below the max of your rifle gives you an automatic saftey cushion.

[KN]

One other problem you may run into is that the different brass loads will probably not shoot to the same point of impact. I once tested three diffrent headstamps of 223 brass, all loaded the same, and all three placed differently on the target. They all grouped the same but printed differently high/low. As much as 1-1/2" at 100 meters.  KN

[beemanbeme]

I'll agree with KN........ but only to a point.  How many deer are killed each year with rifles who's best effort is a 1.5" group. 
For your very best accuracy, yes you must match your components (I tell my none reloading friends to buy 3 or 4 boxes of ammo at a time and make sure the lot numbers are the same) but in the real world of big game hunting, it just doesn't matter that much. (before anyone says "yeah, it can cause a miss at 500 yards", I don't shoot at big game that far away so it's a moot point)
From a safety point, I think it's a non factor.

[KN]

beemanbeme, You are absolutely right. My point was more along the lines of "don't mix headstamps or your groups will suffer  because of the preasure descrepencies"   KN.

[jhalcott]

 I will NEVER tell a person to "Just load ALL your components the same and don't worry" The times I have SEEN people lock up bolts and or wreck a gun from doing this tell me IT IS JUST WRONG! The brass he is using is 17 grains different in weight. Would you care to bet on the length of his cases? I have seen a brand new 270 browning damaged by going "ONLY 1 GRAIN" over the book max. The owner said he'd loaded his Weatherby with that load for years. Another time a guy sighting in his 30-06 using his bro-in laws reloads jammed his semi auto on the second shot.Clodbuster SOUNDS like a new reloader,I for one refuse to tell him to do what I would not do. Of course ,it is HIS fingers and eyes we are betting on. I hope he gets several manuals and reads them .
  RANT MODE OFF! merry Christmas!

[beemanbeme]

I think if you were to read his post, really read his post, he has taken a good bit of the varibles out of the mix. That still doesn't change the validity of my post.
I guess I've been lucky.  I've shot in a lot of places with a lot of different people and never witnessed the things you apparently see on a routine basis.  1 grain over book max?? naugh.  The few times I've seen rifles "locked up" or damaged, it was because the loader was doing something stupid.  The reason pictures like the Sako one are posted is because the are indeed rare.
If you really want to help a new reloader, give him some real-world, common sense information.  Not a bunch of "chicken little" scare stories.  One he finds that "information" is wrong, he may then become a bit too cavalier for his own good.

[jasonprox700]

I really haven't had a problem with different headstamps of brass.  Yes, it does make a difference, but it depends on how much accuracy you really need for what your hunting/shooting.  I've never found a difference between cases in my deer rifle.  The gun shoots 1/2 MOA consistantly.  Same with my .22-250.  I mix brass with no major effects.  I'm sure if I were to sort brass though, my groups would probably tighten up.  Don't load over max and stay about 1/2 to 1 grain under and you should be just fine.

[Sir Charles deMoutonBlack]

A lot of opinions on this thread.  Mostly they boil down to TAKE CARE!  I agree with that.

After taking all the care required  (that means you are using the recommended procedures and had no accidents, or even minor gliches.) the figure I have read ,and worked with, is;

EIGHT GRAINS OF BRASS HAVE THE SAME VOLUME AS ONE GRAIN OF POWDER.

Weigh all lots of brass in your possession.  Use one headstamp, if possible, for each load, especially your most important load be it targets or game.  You say that your WW nickel & RP brass weigh the same?  Do you need to load a lot?  Myself, I'd use one type exclusively until it is too old, and then rework the load with proper procedures for the next.

If I need different loads, whatever the difference, I use a separate headstamp for each, if for nothing but to help me remember!

[Don Fischer]

I seperate all my cases by headstamp. And find that I use pretty much the same charge in each case dispite the headstamp? I think bullet's seated into the lands and to long cases are a bigger problem.

[Drilling Man]

  It's NOT jusy about accuracy...  it's about safety too...

  Different brands of brass have different case capacities, and that means MAX pressure comes with different amounts of powder used in them.

  Always work up a load for each brand of case "seperately", to know what load is MAX in "that" brand of case...

  DM

[RaySendero]

Ditto what Drilling man said!

Worst case I've run across was in 8mm Mauser - 1.5 grains powder difference between Rem cases and S&B!