Hi Brian,
You have to remember that they are thinking from an XTC perspective and the rapid fire requirements of 10 shot strings.
I believe their main issue with the .243AI is the overall length. It's too long to fit in the mags.
The difference between the .243 and 6CM is that the 6CM holds 2 more grains of water. Another thing I found out is that most people shooting 6CM use a 28" barrel to get those velocities.
You have to remember that they are thinking from an XTC perspective and the rapid fire requirements of 10 shot strings.
I believe their main issue with the .243AI is the overall length. It's too long to fit in the mags.
The difference between the .243 and 6CM is that the 6CM holds 2 more grains of water. Another thing I found out is that most people shooting 6CM use a 28" barrel to get those velocities.