Re: Test results from 338 ST *pics and chronograph data*
I tested the 350grn Wildcat bullets this morning. The results were not good. My barrel twist will not stabilize the long heavy bullets. I feel you will need a 10 or under for this. All my new SnipeTac rifles have a 9.25 twist, this barrel was a prototype i had made several years ago for testing this new round. With any new wildcat it takes time and lots of testing to find the proper twist rates. This is a whole new area when you contiplate running 300gr bullets over 3400fps, spin rate becomes an issue, just how much can the bullet take? Therefore you are experimenting with twist rates, can get expensive, or get lucky on the first try! This twist will work ok for 300 and smaller bullets. I have shot 200grn Noslers in this barrel, they all go into the same hole at 100yds, 3900fps. Not an ideal choice for hunting or barrel life, was just for fireforming and test loads at the time.
I shot several of the 147grn loads with the 300MK for sighters. It was 55deg out today and light winds. The same load yesterday at 65deg produced 3420 on ave. Today with 10 deg cooler temp it was 3375fps ave.
I loaded up 3 test loads with the 350grn bullets, 142, 143, 144 with US869. All loads opened easy, little resistance on the last load. Velocity was from 3140, 3160, to 3205fps highest being the last load. I was mostly looking for what speed the 350grn will be capable of running. The recoil was no different from the 300MK.
More testing will be needed with the new 9 twist barrels when i get one done.