Is there a general rule used in gauging a safe time span between shots when establishing the accuracy of a sporting rifle? I would think that some with experience may have established a rest period between shots to allow the barrel etc. to cool to maintain cold bore shot accuracy. Or should one fire a succession of three or so rounds and then let it rest? I have been testing loads for my .257 with a light sporter barrel. Unlike my .222 varmint rifle, the light .257 heats up quite quickly. I have arrived at the idea that the hot condition is effecting its point of impact which has frustrated me to no end. Thanks, Peter.

I don't know of any rule here, just opinion. For a light sporter barrel, anything hotter than what is comfortable on the inside of your wrist is too hot. If you are shooting for group, just shoot slow, take a .22 along so you have something to kill time with. For a hunting rifle, I want to know where that first cold shot is going to go. Some people shoot a fowling shot and then don't clean their barrels till after the hunt. That way they have a known point of impact from a cold barrel and a pretty good idea where the second shot will go if they need it.

Sounds like your .257 is noodling. Each rifle will set it's own parameters. My 7mm Rem mag w/ a light barrel is good for 1 a minute off the bench, but my HB .308 Howa will shoot all day. in 5 shot groups, w/ only time to reload.
Very different set ups! You need to find the Rhythm. JP

I don't know. I always fire three or five depending upon the groups size I need. When I was bench resting fired groups of ten, but was using a heavy bbl. Often when varmiting would shoot a bunch without loosing accuracy, again with a heavy bbl.

Hunting buddy had a Win model 70 standard 26 inch bbl. Sometimes we would put 250 rounds a day thru it and my 22-250. guns were glass bedded and free floated. accuracy didn't seem to suffer. I can't say how many spring squirrel hunts these same guns went on.

I guess I broke all the rules, but I never worried about barrel heating and these guns must have gotten hot. Can't imagine doing 200 shots in an afternoon without some barrel heating. Accuracy didn't seem to suffer.

As for light barrelled hunting rifles, well they always get shot five shot groups at the range. They have time to cool down enough for me to go check my targets then another group. Usually shoot three sets of five or more if I'm working up a load. In the woods those rifles only get fired once or twice in hunting situations.

I would suspect a bedding problem rather than a barrell problem.

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Bob from Idaho

As Lumberjak indicated, the pace of firing and ambient temprature will dictate the heat retention of the barrel. Lightweight barrels tend to heat more rapidly and become erratic usually after the 3rd or 4th shot done within a one minute time span.

If you can't hold your hand on the barrel comfortably, it's too hot. Let it cool. Open the chamber immediately after each shot for circulation. I've even been known to take a length of plastic tubing to the range and blowing down the bore to drive out the residual heat lingering there. In the middle of our extremely hot summers, I've taken a 12-pack cooler filled with frozen face towels to drape over the barrels to aid in cooling. When one gets to be just damp and slightly cool, it goes around my neck and another brought from the cooler.

Keep your ammo out of direct sunlight, too. The cartridges will heat rapidly and pressures will be erratic.

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Spent one summer in Phoenix, actually lived in Buckeye, boy what heat. Anything left in the sun was quickly ready to fry eggs on. God I love Idaho.

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Bob from Idaho