Ok, Ok, this last post got me thinking and I had to make one myself.


I own a few .223 rifles. I use these mainly on prairie dogs. I had a new AR-15 reciever to make another one but couldn't seem to find a hole in my collection that needs filling. I already have WSSM and pistol caliber AR-15's. I thought that maybe there is a cartridge that will fit in the AR-15 platform that will buck the wind a little better than the .224 cal bullets but still be available cheaply and plentifully like the .223.

Solution: 6x45
It uses standard .223 brass just necked up to accept the 6mm/.243 bullets. This means just a barrel change in any standard Ar-15 and I'm in business. I am building one just for this caliber though. Intersting enough the lightest bullet weight that I load (70 grain) in .243 loaded in a 6x45 actually is equal in energy and speed to a 22-250 in a 70 grain. That means I'm not shooting an AR-15 with the velocity of a 22-250 without changing anything other than the barrel. even standard mags work.
Now that same 6x45 can also be loaded with 100 grain bullets, something not possible with the .223, and used to hunt coyotes in stiff wind, even smaller deer or antelope.

Will my .243 do this and more? Sure, just not so economically. The .243 uses the same bullets and powder as the 6x45 but just about 10 grains less powder and brass is waaay cheaper.