My buddy has a ruger in 338. It has a 24 inch barrel. He wants to put a new stock on it and cut the barrel down to 18 or 20 inches. He is willing to lose the velocity, what can he realistically expect for accuracy? He wants to cut the firearm down to reduce overall length so it won't hang up in the thick bush moose hunting.

A 338Win can shoot very accurately out of a 20-22" barrel. It is very common to do what he is doing. In my opinion, barrel length has very little to do with accuracy to a point. Has to do with powder burn rate and consistency in doing that, the thoat length, the smoothness of the barrel, the round of the crown. Just an opinion. I mean, you can't expect to have a 1" barrel and get accuracy.

He probably won't lose accuracy if the job is done correctly but muzzle blast could be severe if the barrel is shortened to 18 or 20".