My .243 700 VLS factory barrel lasted 2,500 rounds or so before it started shooting groups mostly between 1/2 & 5/8 MOA. I switched to a stainless Lilja 12 twist that is approaching 3,000. When shooting loads for development the range has 20 minute periods between cease fires & I limit myself to 1 shot every minute to two minutes to keep barrel heat down. This is a varmint barrel, sporters require more time. If it is real hot outside, I'm in Texas, I use a moist towel past the forearm to help cool the barrel or a dry towel to keep it in the shade. One of the other things that has helped is using bullet lube. I started using moly, then tungsten disulphide( Danzac) and finally hexagonal boron nitride. I think tungsten disulphide is probably the better lube but boron nitride doesn't make the same mess during reloading.
For coyotes I found the 70 grain bullets, Nosler Ballistic tips, Sierra Blitzkings and the Speer TNT in my case, work well out to 500 yards. Chronograph says about 3360 fps for my most accurate loads which isn't blazing fast. In reloading I, sort by weight, trim to length, neck turn to ~.0135 neck thickness, flash hole deburr, neck size after the first firing, polish the id of the neck, regularly anneal and clean the cases. Chronograph & target seems to indicate it all helps and even with the factory barrel.
For coyotes I found the 70 grain bullets, Nosler Ballistic tips, Sierra Blitzkings and the Speer TNT in my case, work well out to 500 yards. Chronograph says about 3360 fps for my most accurate loads which isn't blazing fast. In reloading I, sort by weight, trim to length, neck turn to ~.0135 neck thickness, flash hole deburr, neck size after the first firing, polish the id of the neck, regularly anneal and clean the cases. Chronograph & target seems to indicate it all helps and even with the factory barrel.
