Brass creap

[crashresidue]

Cheers guys,

Be gentle with me - I'm still trying to figure out which end of this thing "belches" and which end kicks.

Just annealed 39 rounds, measured the case length, re-sized and measured cases again.  One round cracked upon firing, which is why the odd number.  See previous post "Yo, The Shrink"

I got an over-all average of 0.01067 creep due to re-sizing, with the biggest being 0.040(RCBS) and the smallest being 0.004(Bell).  I'm shooting three different "brands" - RCBS, CSA, and Bell, with RCBS being the oldest and most shot.

Bell averaged 0.0173 and CSA averaged 0.0164 in creep.  Got too tired to do the math on the RCBS, but it's got to be lower because of the over-all average.

Is this "normal" with this style brass?  When will it quit creeping - or will it fail first?

Gentle winds.
cr

[Charles Vail]

The best thing to do is use one brand from the same lot and fire it all  before reloading . In other words don't mix brass that has been fired 10 times with brass that has been fired 3 times. This is what we do in 1000 yard BR and it results in more even "tension" on the bullet if you are sizing your cases to hold the bullet. The other advantage, of course , in having them all the same is simular capacities. This will give the benefit of more consistant pressures and velocities reducing vertical on the target etc. If you have a "hard to buy brass for" cartridge this makes it somewhat more problematic but it can be solved by saving the money and forking over and buying several hundred cases at once. Different brands may have different alloys making them either softer or harder than others making the annealing process difficult to do consistantly. As with any reloading consistancy in every process makes the most accurate ammunition. If you want to use different brass brands keep them grouped together when shooting and reloading them. My two cents worth! :grin:
The other thing to learn is when to scrap your brass and buy new! This stuff work hardens and doesn't always soften up correctly when annealing I think due to immpurities and or oxides that form when annealing.  :toast:

[Hot Foot II]

Hi crash...,

I know it's that time of day when my brain is a bit drained ( I just got out of work) but what cartridge are we talking about here?  Did I miss something?

Also, what load(s)?  What type of rifle etc etc.  Lots of details please.

Hoppy

[crashresidue]

Cheers guys,

Sorry 'bout the lack of details!  I'm shooting a 45-110, Shilo Sharps, heavy barrel (16#) and I'm using Pyrodex RS at the "equivilancy" of 80 grains BP: ie 53 grains by weight.  Lit off by Remington primers.  Compressed .125 inches in the press.

I'm slowly replacing my brass with all Bell - but it's a might expensive to do it all at once.  So any help would be appreciated.

Do you get much creep after re-sizing?

cr

[Smokin Joe]

...Don't know if this is your problem or not, but an unlubed or under-lubed expander plug can streatch hell out of cases during the "back out" motion of the loading press.

[Hot Foot II]

Mr. Crash,

It’s too bad you don’t have a rifle chambering that gives you more options for where to purchase brass.  If it was a .45-100 or .45-90 things would be so much easier.  

I don’t know if there is some inherent problem with straight wall cases that are longer than the good old .45-70 where brass stretching is more of a possibility but I can speculate that a longer black powder (or Pyrodex) charge column presents more surface to the inside of the case and hence more force trying to shove the brass forward upon firing.  I have .45-70 brass that has been shot 15 plus times with black powder only and has never needed trimming.  It is important while washing to brush the insides of the cases so one does not eventually end up with a rough surface for the bullet and powder column to drag on.  I go even further and spin a bore brush (dry) in the cases just before priming.  I like to see a shiny/smooth inside surface.

A chamber free of lube and moisture from blow tubing etc is desired for every shot also.

One contributing factor could be a headspace problem.  Probably unlikely but the rim cut might be too deep or your brass rims might be too thin.

Overworking of the brass might be a problem too… consider backing off the die to resize just enough for positive chambering.

If you have to trim cases more than a few thous (if at all) with each loading I think something is amiss.  Have you probed the inside of the cases to feel for thinning (ring) and insipient separation?  And if there is a ring, where is it generally located?  Is it near the base/web or further forward, like about half way between the web and neck?  

For a probe bend a wire or paper clip with a little “L” on the end or if you are a gadget fan get one of the RCBS Case Master rigs.  However, for the price of one of those you could get some more brass…. which is what I would do anyway.  

Like one of the previous posters said… one needs to know when it’s time to retire the worn out old stuff…. painful ($$$) as that may be.  I think you have already figured that out though.  So to summarize; get plenty of new, good quality brass, don’t overwork it with your loading/processing technique and keep it real clean, especially inside.


Hoppy