6mm / 243 105 GR A-Max - What Cal?

[helotaxi]

I'd love to go 243 AI, but fire forming is NOT appealing.
Fireforming ai cases is as easy as loading any other round and most of the time the fireform load is just as accurate as the final case.......just not as fast or cool lookin ;) Loaded hot it will eat a barrel within 1000 rounds though.

But still not as fast as a 6-284 will. 6.5-284 has a barrel life of around 800 rounds before the throat is gone. The 6-284 is even more overbore and thus even harder on throats.

Without getting into really obscure and proprietary cartridges, the .240 Weatherby and the .243 WSSM are pretty much as fast as it gets. There are some real screamers out there but all are either proprietary ($$$) rare ($$$) or require custom dies ($$$). Also, none of them are really well suited to any type of prolonged shooting because they will eat a barrel in short order.

A regular .243, 6mm or an AI version of either is more than sufficient to reach out to 600yds, especially with an efficient bullet.

[SMK Shoe]

I seem to remember a article I read in the early 90's about a wildcat cartridge called the "6mm Mach 4". it was a 7mm rem mag necked down to 6mm. quoted velocities were 4100-4300 fps. only problem was barrel was a smooth bore by 1000 rds. Article stated accuracy started to fall off around 400 rds. Was interesting but who wants to change a barrel every other month. LOL

[keeki]

if your worried about throat, just have it nitrided

[snowgetter1]

I am having my 243 wssm shilen nitrided now. It will be interesting to see barrel life, accuracy and velocity when it comes back. And I forgot to metion the the higher post I had it is a 1 in 8 twist.