Has anyone used the cream of wheat fireforming method? Normally I jam the lands with the bullet and fireform, but with components being so scarce, and the price of 338 and 375 bullets, I’m going to give the COW method a try. Any tips or tricks, recipes, or experiences would be greatly appreciated.
JTD
I have always done the JTL method personally. I get not wanting to waste pills, but if it ain't broke don't fix it.
I'm a JTL guy, (or double shoulder if I am down sizing brass) as well, I am interested however in alternative methods.
"Long range shooting, It's like golf, but for men"
Ive been doing a lot of research on line and you tube. I’m going to try it soon, and will post all of my results here on the forum.
JTD
I sized one piece of 30-06 bras up to 358, then started sizing it back down to 338. I stopped when I could close the bolt all the way, with moderate resistance. I’m hoping this will become a 338-06 Improved.
I thought I would have to size more of the neck down, but it fits, so what the hell. I’m only going to .do 5 at first. One with 14gr unique one with 15gr one at 16 one at 17 and one at 18.
JTD
I got my cream of wheat / unique test loads made up. I did one at 14, 15, 16, 17, and 18gr. After I shoot them, I will compare and measure them, if any are good I will load the rest up with that load.
JTD
Well. My first attempt at cream of wheat fire forming was a fail. Brass barely formed at all.
From left to right, 14 15 16 17 and 18gr of unique. Back to the drawing board.
JTD
My method . Recent forming examples 06' to 7×57 and 25-06' , 6.5×50SR Japanese from 243 , and 358 Win from 308 . A couple of these are no brainer run them in the dies and done .
The 7×57 was a more challenging one not hard but challenging . I have lots of dies for things I don't shoot and this comes in handy forming stuff . I run the 06' in a 270 die FL then in a 358 Win die left up about .200 no expanders in . A 9×57 would be a better step than 358 , but it's what I have . Then I can form to 7×57 . Some neck lube is ok but keep it off the shoulder , it makes dents then creases ......dry lube or die wax won't but I'm a dinosaur and use STP on a roll pad . I figure good enough for Fred Huntington and PO Ackley it's good enough for me .
Keep bumping until the first case will close firm like 3-5# on the last half of the cam in a bolt action . An adjustment for the 2nd case may be needed .
Anneal the new neck and shoulder area , don't trim it yet . In this example you should the 270 neck which should clear the barrel dia , the 7mm neck and shoulder and a minor shoulder step .
Leaving the long neck does a couple of things . The big one is raising pressures for the form and instant longer . 2nd it will show you where the end of the actual neck is cut in the chamber giving you a true maximum case length . Not a big deal but for some applications it can be important . In the case of the 6.5×50 SR the neck in the chamber is some .07 longer than the factory or drawing specs the shoulder is where it's supposed to be but the rifle is 94 yr old and lived through a war maybe in service . Paper patch also likes to have mouths .01 or less from the end of the chamber . The soft annealed neck will mark at least a few cases with a visible end line to set up trim length .
Charging . I use only 7-8 gr of Unique or Red Dot under a full case of COW or Grits held in place with a wax plug , I use my paraffin , Vaseline , STP cast bullet lube and would discourage hard wax . Many use a ball of tissue , it's really just there to keep the cereal and powder charge compressed enough to not mix or pour out .
Things like 358 from 308 I moved up in the available steps .318 , .335 , .356 .
Actual brass used will have its own quirks of course . HPX 06' sucks for necking and AI . LC doesn't care for much more than 1-2 steps or calibers with out annealing , FC did the whole process from 1x to 358 and 45 with no annealing . Range pick up should be annealed and sized in it's original cartridge with a few exceptions .
I lost about 25% getting 3 brands of 303&30-40 Krag up to .410 .
The 6.5x50 needed to have the head swaged and be turned down slightly about .1 above the extractor groove . It reduces the body dia down from .473 to .455 leaving the rim .470-.475 . I found it would go in one pass but a half stroke and body relube made it go a lot easier .
The closer you get to straight cases the harder it gets to blow them straight . I used a hot 45 Colts load 255 gr with a .451 Round ball in a 45/410 .
In those where bullet cost is a consideration a Lee push through sizer kit with tumble lube and a box of slightly over sized ML round balls or Buck shot . 30 & 32 cal should work with .330 000B up to .380 is nice for 9mm and 358 . In any case choose a size and sizer at least .002 over groove dia and flair the case mouth enough to get half the ball dia in .
Honorable mention .......
Rimmed cartridges most notably 303 Britt will benefit from an 0 ring placed in the rim groove that forces the case back against the bolt face . 303 is notorious for very fat chambers and profiles that don't exactly match drawings .
In cases like 7.7 Japanese that can be formed from 06' but will be small at the base a lap or 2 of half width Scotch tape as needed will help center the case during fire forming and hold the case back also . Any depression left will fill out the second firing .
That’s a bunch of great info. Thanks for sharing it.
I never finished my COW fireforming experiment with my 338-06 Improved. When 18gr of unique didn’t come close to fireforming the case, it took the wind out of my sails.
I may just use bullets and a standard powder charge or I may up the unique a couple more grains, I haven’t decided yet.
JTD
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