Accuracy from brass

[mountaincarver]

so my latest experience with reloading is my accuracy changed dramatically. known accuracy loads came out of wak and pressure signs didn't make sense. took me a while to figure it all out but I determined it was caused from brass that had several reloads on them. I was amazed to find how accurate I could shoot after replacing my brass with fresh. i would like to hear some experiences and explanations to support this. while sitting at the press, i never detected a problem...

 

[birdiemc]

I would imagine it has to do with the work hardening of the brass. I experienced something almost similar last weekend. I had some brass that was sent to me by an experienced reloader ln this forum that he had annealed. I had to full length size it because it was way to large for my chamber, after sizing, trimming, chamferring, deburring flash holes and uniforming primer pockets, I went to turn necks, there were I think 3 that would not fit into my pilot which is turned to the exact size of my expander. This was brass that had just been annealed and just the normal prep and full length sizing work hardened it to the point that the case neck sprung back undersized. I actually checked with pin gages and it was .001" undersized. So I hit it with the torch, sized again and perfect. All that to say work hardening brass can cause it to spring back differently from case to case resulting in varied neck tension, which will most definitely effect precision.

 

[ar10ar15man]

yep hard necks mean varying neck tension which wreaks havoc on real accuracy.
i anneal EVERYTIME for uniformity.

 

[mountaincarver]

I would imagine it has to do with the work hardening of the brass. I experienced something almost similar last weekend. I had some brass that was sent to me by an experienced reloader ln this forum that he had annealed. I had to full length size it because it was way to large for my chamber, after sizing, trimming, chamferring, deburring flash holes and uniforming primer pockets, I went to turn necks, there were I think 3 that would not fit into my pilot which is turned to the exact size of my expander. This was brass that had just been annealed and just the normal prep and full length sizing work hardened it to the point that the case neck sprung back undersized. I actually checked with pin gages and it was .001" undersized. So I hit it with the torch, sized again and perfect. All that to say work hardening brass can cause it to spring back differently from case to case resulting in varied neck tension, which will most definitely effect precision.

makes sense. I did start to notice that my trimming pilot was not lined up with the neck on more as time went on. most of the time I could rotate the case and make it better. I have to wonder if this is due to case thinning by the head stretching more on one side....

 

[birdiemc]

Are you turning your necks multiple times? I'm new to the neck turning game but from what I understand it's a once and done thing...but could definitely be wrong

 

[mountaincarver]

Are you turning your necks multiple times? I'm new to the neck turning game but from what I understand it's a once and done thing...but could definitely be wrong

no, im talking about trimming case lenghth, not turning.

 

[Kansaswoodguy]

My 6.5 creedmoor seems to benefit from annealing about ever 4th firing I think it would be better every other but I don't have one if the automated annealers so it's a pain to do.

 

[ar10ar15man]

but it is also a 6.5 cm not sure anything will help....lol

My 6.5 creedmoor seems to benefit from annealing about ever 4th firing I think it would be better every other but I don't have one if the automated annealers so it's a pain to do.