A good friend of mine from Wyoming just built the second 338 thunder and we got out to test it finally.
He built this gun as a switchstock rig for benchrest and for hunting elk and everything else in Wyoming. He used my gun last fall to kill an antelope at 1086 yards and just had to have one.
I lent him my reamer and dies and we found some interesting things in load development. Despite having a totally different lot of powder, his gun liked the same load and shot nearly identical speeds. This cartridge has something to it as we have now fired 6 different loads in his gun with the largest standard deviation being 12. Most of the other loads are in the 2 or 3 fps range!! My gun was like this too. I believe it is the 40 degree shoulder that is doing this and the right powders.
Anyhow, back to his gun. It is built on a Stiller Predator action, Lilja barrel, Mcmillan stock, Jewell trigger, Leupold scope, and Vias muzzle brake. Smithed by a guy here in Utah.
Of the loads we tried in our one and only range session, the biggest group went .75" and the smallest being .272". THIS GUN SHOOTS!
Powder was RL22 and the bullet is a 225 grain Nosler Accubond (yes we realize the 300 grain MK has a higher bc as does the 250 grain Scenar but we want this gun to actually KILL something) and the primer was a Fed 215 gm.
With any luck, this gun will kill a heap of game this year. My friend has two cow elk tags, one bull elk tag, three antelope tags, one deer tag, and he is a fox hunter the rest of the year for bounty.
Here is some pics of the hardware: