Case Hardness

[mike06]

Guys I bought some Peterson 308 SRP cases a year ago. I have since fired and reloaded them at least thirty-five times. I anneal the necks after each firing. I have done full resize and neck size only and even used them in two different rifles both factory chambers. I have not had any splits on any of them and the primer pockets are still tight. I have notice that they are getting a little harder to full resize. I guess the case body is getting work harden. Do you think I am getting near to the end of the case life or keep loading them until they start splitting? Thanks Mike

 

[ormandj]

Probably nearing lifespan. I've heard of some people getting up to 50, but if you're feeling a difference the brass is telling you what's going on. I agree with your assessment, it's probably work hardening. You can keep loading but keep a close eye on things. Do the paperclip thing to check for any potential case head separation to be safe (bend a little right angle and pass it down the case and up the inside wall feeling for ridges, starting at base and moving up.)

As always YMMV, you'd need equipment to measure hardness to really know what's going on, and better safe than sorry if it starts getting worrysome. Keep loading at your own risk, but definitely check with a paperclip on every loading moving forward imo.

 

[mike06]

Probably nearing lifespan. I've heard of some people getting up to 50, but if you're feeling a difference the brass is telling you what's going on. I agree with your assessment, it's probably work hardening. You can keep loading but keep a close eye on things. Do the paperclip thing to check for any potential case head separation to be safe (bend a little right angle and pass it down the case and up the inside wall feeling for ridges, starting at base and moving up.)

As always YMMV, you'd need equipment to measure hardness to really know what's going on, and better safe than sorry if it starts getting worrysome. Keep loading at your own risk, but definitely check with a paperclip on every loading moving forward imo.

Thanks I use the paper chip in my Ar's and in LC brass. I only use the Peterson in my bolt rifles and just a thought I can use my bore scope also. I should have thought of that in the first place.

 

[Texas10]

IMOP, the real tell as to case life is how many times you've trimmed the mouth to make maximum allowable case length. I don't have a firm answer to that so I'm wondering if someone else does. Is say, five times across the trimmer considered the end of the line for a case?

I have tossed cases that were split longitudinally in the case wall, not the neck, suggesting too much brass migrated up the case wall to the mouth.

How much trimming is too much?

In my 223 Rem which I neck size only the brass, I start to get "bolt click" when opening the bolt after firing on cases with more than a dozen loading. This refers to hard extraction caused by the case wall not springing back enough after pressure drops during the firing cycle. In this case, the brass is too work hardened from repeated loadings, and is not sized back to factory case wall dimensions because I'm neck sizing only.

Still produces small groups though.

 

[Uncle Ed]

How much smaller in body diameter are your cases after sizing vs the fired diameter. Meaning how much is your die reducing the body diameter. Chambers and dies vary in size and your die could be on the small side of tolerances.

The first thing I do when the sizing effort increases is polish the die with a snug fitting shotgun cleaning mop and J&B bore paste.

Pausing for a few seconds at the top of the ram stroke reduces brass spring back after sizing.

Hard sizing to me is sizing once fired Lake City 7.62 brass that was fired in a machine gun.

What would bother me more is stretching and thinning in the base web area that will cause a case head separation.
I use the RCBS case mastering gauge below to check for stretching and thinning that measures in thousandths of an inch.
(excessive compulsive $100.00 bent paper clip)

Below a endurance test of various .308 cases. Look at the bottom chart and at which number firing the cases started to stretch and thin before separating.

 

[mike06]

UncleEd I will check and see how much the body is being reduced after sizing and see what I come up with. The stretching of the case I have seen that before but not so much with these cases. I also will polish and clean my dies. I use to only neck size for years. If I could rechamber the fired case without any difficulty I only neck size. I use a Redding body die a redding micrometer bushing die also have a redding type s FL bushing die and last of all a Forster Bushing bump die. Thanks for you reply. Texas10 I don't trim everytime do to the fact of the Remmington Lawyer Chamber having a extra .0020 in chamber length.

 

[338 dude]

Guys I bought some Peterson 308 SRP cases a year ago. I have since fired and reloaded them at least thirty-five times. I anneal the necks after each firing. I have done full resize and neck size only and even used them in two different rifles both factory chambers. I have not had any splits on any of them and the primer pockets are still tight. I have notice that they are getting a little harder to full resize. I guess the case body is getting work harden. Do you think I am getting near to the end of the case life or keep loading them until they start splitting? Thanks Mike

I may load mine 10or12 times but I have never heard of loading them so much a 308 is fairly mild but why risk etching your bolt face or chamber when you have a case separation

 

[Stepsjframe]

I had noticed the phenomenon when pulling bullets...didn’t have a fancy force gauge to tell me exactly how much the difference was, but it was noticeable... which caused me to do an internet search which turned up that article.

 

[cw308]

Mike06
A least thirty five times , even annealing your brass there comes a time . At one time I used the same 30 cases of 308 for one shooting season to see how long the cases would last , stress cracks on body and necks also loose primer pockets . When one case showed any of those signs I dumped the lot , I got 22 reloads and saw a slight crack . That was just a test . I now use 3 sets of 30 cases , fire 30 cases each weekend and rotate the lots . I full size only to .001 - .002 , trim to the same length every week . I'm not getting any problems , probably because I'm reloading each group about 10 times . Then in the winter I prep 30 new cases 3 different brands , uniform pockets , make sure flash holes are the same size and deburr , trimmed and sized to the same length . I have plenty 308 cases a shooting friend gives me all once fired store bought brass . FC , HSM and ADI .

 

[mike06]

Mike06
A least thirty five times , even annealing your brass there comes a time . At one time I used the same 30 cases of 308 for one shooting season to see how long the cases would last , stress cracks on body and necks also loose primer pockets . When one case showed any of those signs I dumped the lot , I got 22 reloads and saw a slight crack . That was just a test . I now use 3 sets of 30 cases , fire 30 cases each weekend and rotate the lots . I full size only to .001 - .002 , trim to the same length every week . I'm not getting any problems , probably because I'm reloading each group about 10 times . Then in the winter I prep 30 new cases 3 different brands , uniform pockets , make sure flash holes are the same size and deburr , trimmed and sized to the same length . I have plenty 308 cases a shooting friend gives me all once fired store bought brass . FC , HSM and ADI .

I also have had signs loose primer pockets and split necks in other brands but this Peterson only shows being a bit harder to resize the case body. It gets harder about 2/3 to 3/4 down the length of the case. I anneal the necks so no problem there or the primer pockets.

 

[mike06]

Mike06
A least thirty five times , even annealing your brass there comes a time . At one time I used the same 30 cases of 308 for one shooting season to see how long the cases would last , stress cracks on body and necks also loose primer pockets . When one case showed any of those signs I dumped the lot , I got 22 reloads and saw a slight crack . That was just a test . I now use 3 sets of 30 cases , fire 30 cases each weekend and rotate the lots . I full size only to .001 - .002 , trim to the same length every week . I'm not getting any problems , probably because I'm reloading each group about 10 times . Then in the winter I prep 30 new cases 3 different brands , uniform pockets , make sure flash holes are the same size and deburr , trimmed and sized to the same length . I have plenty 308 cases a shooting friend gives me all once fired store bought brass . FC , HSM and ADI .

I know I have got my moneys worth for sure. I was just wondering if anyone else was using Peterson brass. Peterson did do a test that showed no failures after thirty firings also.

 

[Rsadams]

I read through the post and there's some good advice... My advice is you got your money's worth.... Why chance it.. I shoot automatics so we loose them or it just rips them up..... If I can get 10 I got my money out of them , your at 35....

 

[dmoran]

Besides how hot or mild a person runs there loads, the chamber dimensions in comparison to the mother case dimensions, fallowed by the die dimensions in comparison to both, all play a huge role on the amount of case hardening per cycle and brass life.

Sort to speak, one persons setup may be with a tight chamber and dies that hardly let the brass expand at all, while another person with the same caliber may have looser dimensions, causing the brass to expand more, and yield sooner.

My 2-Cents