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Redding form/trim die instructions

PBking51

Gold $$ Contributor
I recently bought a Redding form/trim die for converting 7mag brass to 350 rem mag. I understand how the die is supposed to work, but no idea on how to set the die up. It did not have any instructions in the cardboard box it came in.

Any help is appreciated.
 
Run the F/T die down in the press so that it contacts the shellholder. Lube case, Run case up into the F/T die, Cut excess off with hack saw or cut-off disk (Dremel), Trim case to smooth out rough edges and to get proper case length, use mandrels to expand case to desired size, ANNEAL the Nk/Shoulder, Run through FL sizing die, check case length again, Load to fire-form. If your 1 st case comes up short after the final sizing adjust the F/T die UP a little for the rest of them.
 
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Run the F/T die down in the press so that it contacts the shellholder. Lube case, Run case up into the F/T die, Cut excess off with hack saw or cut-off disk (Dremel), Trim case to smooth out rough edges and to get proper case length, use mandrels to expand case to desired size, ANNEAL the Nk/Shoulder, Run through FL sizing die, check case length again, Load to fire-form. If your 1 st case comes up short after the final sizing adjust the F/T die UP a little for the rest of them.

Thanks for the rundown. Going to 7mm mag to 350 mag still requires to be fireformed? Any recommendations for loads for fireforming using 158gr pistol bullets?
 
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Thanks for the rundown. Going to 7mm mag to 350 mag still requires to be fireformed? Any recommendations for loads for fireforming using 158gr pistol bullets?
I can dig around and see what I can find in some of my old or CB load data.
I highly recommend virgin brass. I had some once fired and couldn’t get it sized down enough right above the belt.
It is a fine cartridge, but not what I would consider a rig to play with much at the bench.
 
Anytime I load for the 7mag I run brass through my larry Willis collet die. This eliminates the brass flow at the belt
 
Here's the first dummy round I made with a 200gr Barnes original. Coal 2.870. Just wanted to see if it would chamber.

I set the die up based on @CJ6 's advice, then cut off, trimmed to length the 7mag brass. Then ran through my collet die to address the bulging case above belt issue I find on mostly all factory 1x fired belted cases. I then Applied a tad of imperial to the inside of the case neck and ran through a lee 350mag FL die with expander/decapper installed. Feeds and chambers perfectly in my Rem 673.

With the scarcity of primers and components, any idea on performance of the first firing without fireforming? I'm thinking , make 20 piece of the brass and use to sight in rifle for 100 yards. I don't forsee using this rifle at the beginning for shots un excess of 200 yards.
20220310_092200.jpg
 
Performance will depend on how it's loaded (powder wise). Most times a F/F load are fairly descent group wise.
 
I wonder why redding lists on its website "338 win mag to 350 rem mag"...maybe because .338 is closer to .358?
 
I would get the cases annealed before shooting them. Good chance of splitting them otherwise.
 

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