Re: Match barrel Vs Fluted barrels
I don't know how big the barrel is now, but, I wouldn't think that 10 shots should be a problem. That is part of the trouble of shooting 1K like we do in a match is the barrel temp going high enough to make the groups open up. The 338LM is a BIG gun and if this is a lightweight barrel, it's gonna get pretty hot because it has no mass. You said it's a fluted barrel so it must be a heavy bbl gun, and again, you are the best person to decide if it's opening up or not. I don't have a cartridge that big on any of my guns, but, none of them seem to get wild after 10 shots either.
As for "Match" barrels. I have had all my match barrels fluted until the most recent one and I would have done it if the company would have tapered it and done it. I've had people say that fluted barrels have no place in match shooting, yet, the annual aggs have been won with them so who knows. I cannot find a difference in performance between the fluted and straight barrels. I like the way they look and they're easier to hang onto. They are stiffer for barrels of equal weight and length, but arguements go both ways on that too. I will say this, if your gun opens up and gets wild after only a few shots, it's not the flutes in the barrel.
If you have something that you disassemble and reassemble enough times, sooner or later, you'll have two!