Using 7x57 brass to make 6mm Remington brass

david g ranes

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Anyone have first hand experience on making 6mm Remington brass out of 7x57 brass. How did it work and any problems making it work thanks. David
 
Been there & done that about 8 years ago.

PPU 7X57 brass from Graf's.

Neck down to about .290 OD using .260 R die without expander/decapper with die backed way out so no contact with shoulder.

Lube inside necks with powdered graphite, then neck down to 6mm using 6mm Rem die with expander/decapper, some brass spring back happens

Turn necks to .268 - .270 OD (.270 - .015 - .015 = .240, bullet diameter = .243)

Fire Form COW (cream of wheat or cream of rice, raid pantry).

Decap & clean & inspect insides of brass for FF debris.

Anneal - toast with propane for 1 min

F/L size using 6mm Rem or 6mm AI die without expander/decapper - working on uniformity & run-out concerns with annealed brass.

Trim & chamfer necks. 7X57 brass is a tiny bit shorter than 6mm Rem but trim to make uniform.

I took about 1 week to process 100 & used them for about 8 cycles. No problems but lots of work.
 
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Darn it I bought 100 pieces didn't think it would be that much trouble the way people talked thought I would be able to just size and shoot glad I don't have much invested. David
 
Probably would not take that much effort except I am real fussy. Take a few short cuts, like neck down to 6mm with 6mm F/L die, turn necks, trim & F/F. Turning brass necked down from 7X57 is advised - neck walls will be real thick. Be sure .243 diameter bullets slip fit into fired cases.

If I can do it, anybody can do it.
 
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I'll see how it goes not the first money I've throwed out the window keep thinking I'll grow out of that but maybe not. David
 
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