Can someone tell me more about these calibers? I'm looking at a couple of CZ 550 full stock rifles one in each caliber... I know a little about the 7x57, but have no first hand experience with either round...

Thanks!

Kevin

The 7x57 is the original Mauser round developed in the early 1890's. I have two of them and find them excellent deer rifles. If handloaded, it falls between the 7mm08 and the 280 Rem. Commercial ammo is downloaded as to be safe in older rifles.
The 7x64 Brenneke round was developed in the early 1900's and is almost identical to the 280 Rem. Both of thse rifles would be excellent choices.