303 British S&B brass question

303's have sloppy chambers and that is mostly the reason why you get case separation. I would anneal the once fired brass. The idea is then to keep the case against the bolt head when firing. Using an O-ring (see below) the case is pushed hard against the bolt head and the expansion then is more uniform and should help to better fireform the cases. Thereafter you need to resize carefully so as not to push the shoulder too far back, or just neck size. That will help in getting more life out of them.

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Thanks Tripod. I did the o-ring thing using my daughter’s braces elastics with the last batch of ammo I fired. I have around 40 odd PPU/S&B that I have fired in this way and just neck sized. I have an older batch of around 80 PMP/S&B that have only been neck sized prior to me learning about the o-ring trick. Will anneal the cases going forward.

3 firings anneal. Repeat. You will get about 10 - 12 firings if your head space is not too bad.
Another thing is to just shoot gentle loads, squeezing that last 150 fps out a .303 lee just ain't worth it.
As for OP, I have not yet found the S&B to be different to other case brands.
I induction anneal for people R3.50 incl return postage, minimum 100 cases for out of town.

Thanks Treeman.Not looking for high velocity in the 303. Still a while before I reach 3 firings. Will contact you when I do.

If you anneal after every firing you have cases that are exactly the same every time.

Thanks Treeman.Not looking for high velocity in the 303. Still a while before I reach 3 firings. Will contact you when I do.

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