Re: Barrel cooling devices / practices
In long range competition shooting from prone, it's common to shoot 25 to 30 shots with each one about 20 to 30 seconds apart. Barrels from such firing heat up very much. If they're properly heat treated and fit to a receiver whose face is square with the bore/chamber axis, hot barrels don't hurt accuracy. They all maintain sub 3/4 MOA accuracy at 1000 yards. This is for the mild 6.5x.284 up through 30 caliber magnums.
I've shot 30 shots at 20 second intervals testing 30 caliber magnum loads at 1000 yards. All 30 went inside 6 inches. Friend of mine shot 40 shots at 600 yards also about 20 seconds apart; group was 1.92 inch. I put 20 rounds from a .308 Win. at 800 yards into 3.2 inches fired at the same rate. Love shooting fast with those super hot barrels made by Kreiger, Obermeyer and the older ones from Hart. And even those skinny Springfield Armory Arsenal match grade barrels made for 7.62 NATO Garands would hold 1 MOA accuracy at 1000 yards for 25 to 30 shots fired just as fast.
If you barrel shoots bullets to different points as it heats up, you might need to fix the receiver face. Or send the barrel back to its maker and ask for a replacement that's properly stress relieved by good heat treatment. Of course if these typical causes ain't the problem, then maybe you should check the shooter's long-term shooting technique for accuracy at the target.
Last edited by Bart B; 11-07-2011 at 10:06 AM.