Custom Build Caliber Suggestions.

[lancetkenyon]

I think any 6.5 pushing 140's at 3,000+ will be a barrel burner. The exception is supposed to be the 6.5saum running only h1000 with a long barrel to keep pressure low. The 6.5-284 is pushing hard to get to 3,000 thus will be hard son barrels and so will the 6.5-06 and 6.5 Sherman. If you are keeping it a standard bolt face the 280ai is about your only choice and not one you will be disappointed with.

The 6.5 Sherman, 6.5SS and 6.5--06AI will push a 140 to 3150-3200fps. If loaded down to 3000fps, those would he very mild in those cartridges. So no worse than a 6.5 SAUM.

 

[Timnterra]

The 6.5 Sherman, 6.5SS and 6.5--06AI will push a 140 to 3150-3200fps. If loaded down to 3000fps, those would he very mild in those cartridges. So no worse than a 6.5 SAUM.

I only hear good things about all the Sherman cartridges and I am going to eventually try one, probably the 6.5 sherman. With that said I don't see how it is physically possible to push the same bullet at faster speeds using less powder and not have higher pressures. This claim defies the laws of physics. This was George Gardiners premise while developing on the Gap4s; a larger case capacity shooting more slower burning powder can achieve the same velocity with lower pressures. This lowered pressure is how it is supposed to be able to achieve longer barrel life. I know neck length has something to do with barrel life and that is probably why the 6.5-284 is hard on barrels. For what it's worth, while loading for my 6.5saum I've had pressure signs at only 2850 FPS. The barrel is only 18", not what the saum is designed for.