On this matter I agree with
@Bart B. but he'll explain it better than I can, truing your action will be MUCH more productive than slapping on a new barrel. The overheating issues tend to be exhibited most when things aren't quite square.....if I remember right Bart says he tests his groups in a HOT barrel or maybe sights in with a hot barrel?? Hopefully he'll chime in soon, obviously his purposes and mine are not the same BUT I believe that on many concepts I agree with him. As for the shilen itself, I apologize I have no experience with them but I will still address how I feel about whether their WORTH it. A .243 is supposed to have an accuracy life of 1500 rds because it's so overbored. This is drill a chipmunk's boogers at 600 yds with trued action type of accuracy. Hunting accuracy barrel life is of course longer. For the price of a shilen/bartlein/Hart grade barrel, I always ask, will I burn it out in 1,2,3 or 4 years? If so, am I OK with spending $xxxx which equals $xxx/year OR $x.xx per shot for my purposes? For sporting purposes I still wear out barrels fast, and expect a .243 to only last 2-4 years, (though that number is growing slightly as the .223 is taking over MUCH of the battle on prairie dogs, but will probably shrink back again as they're all becoming more and more enthusiastic with the sport) so for me, a new barrel isn't too bad regardless of cost, not awesome, but easy enough to live with. Ultimately noone but you should decide whether it's worth it as we're not the ones paying your bills nor squeezing the trigger for you
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