That is some impressive shooting based on the fact that the diameter of the bullet is .338 are you shooting 5 round groups?? what kind of rest are you shooting from?
I had a HS savage 338 lapua and had pressure problems with the chamber being under cut and cases sticking, by the time I got the pressures down the velocity was well below average. I choose to send it off and have it rebarrelled it now shoots sub .5 moa routinly with a brux 30" stainless match grade tube.
If I had it to do again I would have just saved and had a custom made to begin with. JMHO
Mine was accurate, but the pressure issues scared the hell out of me and I told savage so like I said in order to get safe pressures I had to reduce my load to the point where the velocity was terribly low.
The 338 lapua aint a poor mans gun brass and bullets will break a guy