or.... run your 308 with 150grns at 3000fps VS doing it with a bigger cartridge ......your 308 will be straining everything to achieve it.....the bigger cartridge can do it with ease...
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or.... run your 308 with 150grns at 3000fps VS doing it with a bigger cartridge ......your 308 will be straining everything to achieve it.....the bigger cartridge can do it with ease...
Simplification:
Heavy and slower is easier on the barrel, ok short range, and better far downrange.
Light and fast is hard on the barrel, excellent at short range, but loses it far downrange.
So once you have a rangefinder and can cope with rainbow trajectories no need for maximum velocity obsessing.
Greetings Hermitage,
There is no doubt that reduced pressure will reduce throat erosion but the variable you have missed is projectile diameter. The .308 has 60% more throat area than the .243 ( circumference proportional to the square of diameter) so this may turn the tables on erosion. I suggest you do some comparisons using the barrel life calculator to get a better understanding of the effect of the four main variables. The calculator, while imperfect, is based on science rather than guess work.
Regards Grandpamac.
Greetings All,
There is another factor that can effect barrel life and that is the projectile. About 1980 I was working for the late Tony Loughnan who some will remember as a full bore target shooter. One of the things he told me was that he changed the barrel on his rifles after about 1,000 to 1,200 rounds when accuracy started to decline. At the time the NRA allowed only the NATO 144 grain projectile and most shooters handloaded. To get any sort of accuracy many shooters used Shultz and Larsen 1 in 14 inch twist barrels that had tighter than standard bore and groove dimensions. Tony also sorted his projectiles for weight and exposed lead size at the base which also no doubt helped. Regardless as soon as the first signs of erosion appeared accuracy went south. Tony had two target rifles so he always had one he could use while the other was having the barrel changed.
The barrels were not shot out and still gave excellent accuracy with hunting projectiles. The problem was the projectile and not the barrel. Many of those take out barrels were fitted to hunting rifles and gave long service thereafter. One of Tony's barrels is in my Martini and is more accurate than some new rifles.
Regards Grandpamac.