Looking at it on paper their does not seem to be much of a difference. I have heard the .6mm is underpowdered in factory and about equals a .243. But if you reload (and I do) then you can reach the .6mm's true potential? Is this true or did I misunderstand someone? Thanks?

The 6mm has a bit more case capacity. The .243 is based on the .308 case, the 6mm is based on the 7x57 case.


Yes.

about a 100 fps 6mm being the faster.

I find them to be both faster and slightly more accurate

6mm remington is the faster one.

Having had both of these, I liked the 6MM Rem a little better that the 243. It seemed to have a little more killing power. I did however use different bullets in the 6MM Rem.

Does any manufacture make a left hand .6mm bolt action?

You are correct there is very little difference. In fact any of the cartridges where the same bullets are loaded in the basic .308 and 7x57 cases show the same thing. In order to get more velocity out of the 6mm you have to load it to a higher pressure, and then you won't get an increase of 25 yards in trajectory. Check 'em out in the manuals. .260 Rem, 6.5x55/57; .7mm-08, 7x57' .243, 6mm. there ain't anywhere a 200 fps muzzle velocity difference in max loads with the same bullet.

Any difference is negligible and almost unmeasurable. Both are excellent cartridges.

And that, my friends, is the most accurate, lucid, fundamentally sound post I have read to date. Good job Vapodog.