Cream of Wheat Fire Forming Question

Triple BB

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I had a 100 rounds of new RP 300 RUM brass that I resized for my 338 Edge. Later on I picked up several boxes of ADG 338 Edge brass, so I resized the original brass back to 300 RUM. However, the shoulders are pushed back further than they should be. I've never fireformed with CoW, but want to give it a try to save costs and wear on a newer barrel. I've got some RL26 that I'm not using. What I've read with the CoW method; its add powder, toilet paper to separate powder from CoW and then a small cap of bar soap or wax. Question, how much RL26 powder would be a good starting point? Appreciate any suggestions to do this easier or safer. Thanks
 

MagnumManiac

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Unfortunately, you cannot use a powder like RE26 to do this.
You require a fast pistol or shotgun powder like Clays or Universal.
The idea of doing it this way is that the pressure obtained blows out the case gently and doesn’t stretch the web.
Please do not try this with RE26, detonation is a real prospect with slow powder in small amounts, even with TP as a plug for the case.

Cheers.
 

GLTaylor

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Additionally, the tissue paper is not to separate the powder and cow. Put a fast shotgun or pistol powder in the case, pour the cow/grits in on top of the powder, fill up to the case neck. Then seal the mouth with tissue wad or soap. The tissue is just to keep the cow/grits from falling out into your action while fire forming/handling the shells.
 

GLTaylor

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Both of those are also slower. You want a Fast powder. I usually use powders between Bullseye and International.
 

waspocrew

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Like others mentioned, you’ll want a fast powder like bullseye. I’ve used Unique but felt it was a little slow.

When I started, I filled a case to the neck with powder, then weighed the charge. I then divided the charge in half and started 2 gr below that. Then fill the case with COW and tamp it down with a bit of paper towel. You can then inspect the shoulders and adjust the charge if not forming enough.
 
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Seabeeken

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Just how far back did the resize move the shoulder? It will need to be held against the bolt face by something. In my ackleys, it held by the neck shoulder junction. Im wondering if there is excessive headspace. If so, it could stretch just ahead of the web or separate completely
 

LongBomber

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To get a good fireform you need to expand the neck and get a good false shoulder to hold the case back against the bolt face. Then run a fast powder (i use green dot) and cow.
 

Triple BB

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Went to a local sporting goods store to see if I could find any of the above powders. Picked up a lb of Universal and these primers which I was surprised to see...
Primers.jpg
 

parshal

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Just be sure to clean or check the inside of your cases for any packed in cow residue. There was a thread on this recently.

I fireformed about 500 65SS cases and can attest to this. I wet tumbled and then looked in each case with a bore scope and found COW in the should area on a lot of cases. COW fireforming works but just keep and eye inside the cases. I used Titewad for powder.
 

jrock

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I have not looked into fire forming larger cases but the small Dasher cases I fire form, I used titewad. It worked great. After 3 shots, the barrel was very warm. Plan for a lot of cooling time.
 
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