02-09-2017, 03:11 PM
I stand corrected. My answer was based on what Von Gruff told me once:
Giday Drillbos and no the factory ammo cant because of the headspace which is .050 longer with the GM. I did get a couple of boxes of Hornady ammo when I first built the rifle more to get the brass than anything else and debulleted, saved the powder in another set of cases, expanded the neck to 30 cal then necked back down in the Grendel dies with a .05 spacer glued to the shell holder which is a permanent fixture that stays with the Grendel dies. This is how all reloading is done but for the first necking down I added a .006 shim to give me a crush fit in the chamber, added the powder backinto the cases and seated the same bullet to an OAL of 2.405. The GM case gives me a near 10% case capacity advantage but with the bullet seated long it opens up more space for the powder so that with 32.6gn CFE223 under the 123gn bullet I get 2700fps from my 21 in barrel and at just 53K psi. The 100gn ttsx gets 2950 but the 123gn has a better long range performance with less elevation and windage drift.
Without a doubt the most efficient and usable rifle I have built (other than a little 20 VarTarg that is)
Giday Drillbos and no the factory ammo cant because of the headspace which is .050 longer with the GM. I did get a couple of boxes of Hornady ammo when I first built the rifle more to get the brass than anything else and debulleted, saved the powder in another set of cases, expanded the neck to 30 cal then necked back down in the Grendel dies with a .05 spacer glued to the shell holder which is a permanent fixture that stays with the Grendel dies. This is how all reloading is done but for the first necking down I added a .006 shim to give me a crush fit in the chamber, added the powder backinto the cases and seated the same bullet to an OAL of 2.405. The GM case gives me a near 10% case capacity advantage but with the bullet seated long it opens up more space for the powder so that with 32.6gn CFE223 under the 123gn bullet I get 2700fps from my 21 in barrel and at just 53K psi. The 100gn ttsx gets 2950 but the 123gn has a better long range performance with less elevation and windage drift.
Without a doubt the most efficient and usable rifle I have built (other than a little 20 VarTarg that is)