fire forming brass ... what poweder to use ?

burnt_servo

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I am going to fire form a couple hundred rounds .

I have read a few threads where guys are using 10 -15 grains of bullseye , topped with cream of wheat with a paper towel cap .

I have imr 4227 , lilgun and trailboss , would any of these be fast enough ?

and if so what size of powder charge should I be starting at ?

if it matters , the case I am fireforming is a 9.3x62 brass with the shoulder pushed forward almost 100 thou .


what other powders might work for doing this instead of bullseye ..... ( no one has any bullseye in stock right now ) .
 
I've used fast shotgun powders and cream of wheat, wax, or packed in paper towels before and none of them fire formed as well as a light regular load.
Most cartridges I fireform I just use starting loads and a light-medium weight bullets.
For cartridge conversions I tend to use cast bullets and a fast-medium burn rate powder such as H4198 or SR-4759. Cast bullet data still produces enough pressure to obturate the case but are usually 30-50% below max pressure.
 
My old standard for 303 British to .410 brass shotshells was 15gr of Reddot and top it off with cream of wheat and hot glue. I had to fire each one 2-3 times to get it to fully fire form though because of the low low pressure. With a cast bullet load at ~50% max pressure it would most likely only take one shot.

*edit*
15gr, wait, no, that can't be right. I believe it was 5gr.
A quick Google search shows people using 7-20gr so perhaps it was 15gr.
I forget but with cream of wheat there isn't enough weight to produce significant pressure anyway.
 
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I use about 4.5 to 5 grains of pistol powder/shotgun powder when doing my 308 brass to 7-08, topped with cream of wheat.

I guess 7 would work for you.May have to clean a bit as there are some deposits that may get into the chamber.
 
I've used fast shotgun powders and cream of wheat, wax, or packed in paper towels before and none of them fire formed as well as a light regular load.

X2. No mess, no fuss just perfect case first time plus you get to do some real shooting while fire forming, win, win, win.
 
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