04-10-2012, 07:15 PM
The hardest part of fire forming 7.62x39 into Grendel brass for me, is the expense of the of the projectile. There just isn't a projectile under $19.00/100. And I have about 1500 7.62x39 cases to re-size and fireform. If you plan on reforming brass for your Grendel, get a set of 7.62x39 dies (or just a sizer die) as well or you will ruin alot of the brass trying to re-size it straight to the 6.5mm diameter. Use the 7.62 sizer die to deprime and bring the mouth of the case to a near perfect circumference. You will not need to full stroke with the 7.62 die so there is no need to lube the cases for either of the sizing operations; only after you have fired the 7.62 case into a Grendel case will you need to lube for full length sizing, and every time then on till you discard the case. Its not a difficult task, just time consuming, and in the end; I feel for me, that it is worth the effort! I have a batch of 7.62 cases on their 5th reload!
PS: Stay away from Winchester Large Rifle Primers, the cups are very soft! I have used S&B LR and Wolf .308 primers with good results!! Also when Fireforming 7.62 cases use a powder charge close to or just under the starting weights and seat a smidge deeper, I use 25gn of Benchmark and seat Sierra 120gn Spitzers to 2.225" COAL.
PS: Stay away from Winchester Large Rifle Primers, the cups are very soft! I have used S&B LR and Wolf .308 primers with good results!! Also when Fireforming 7.62 cases use a powder charge close to or just under the starting weights and seat a smidge deeper, I use 25gn of Benchmark and seat Sierra 120gn Spitzers to 2.225" COAL.