Originally Posted by meat head
Kirby, this may sound stupid but how do you fire form one in corn meal
In my wildcats based on the 338 Lapua parent case, those being the 277 AM, 7mm AM, 300 AX, 338 AX and 375 AX, I use 16.0 gr GreenDot over a Win Large Pistol Primer(non magnum), then fill the case with plain yellow corn meal. Tamp the case down hard three or four times to settle the corn mean, then make a wad from 1/4 sheet of TP and press it into the case neck with a punch until everything is compressed tightly. Clean case and fire.
For my RUM based wildcats, I use 14.0 gr Green Dot. These include the 257 AM, 6.5mm AM, 270 AM and 338 Ultra Maxx.
For my 408 Chey Tac based wildcats, I use 22.0 gr Green Dot with the same technique as above. These include the 338 AM, 375 AM, 410 AM, 50 AT.
I use green dot because I can get by with using less powder and still get the job done. When your forming thousands of rounds for customers every year, getting by with 10-15 grains less powder per fireformed case adds up to a decent amount of savings.
Use large pistol primers simply because they are plenty hot to ignite the handgun powder and they will also tell me if pressure are getting a bit higher then I want as the thinner cupped handgun primers will flatted much shooter then a rifle primer. If you see ANY primer flattening, your way over pressured or your headspace is to loose.