Originally Posted by vatackdriver
The 243 wssm or 25 wssm would be fine candidates and there happens to be one of these for sale on this forum. I have a coworker that let's his granddaughter hunt w/ his 6br, she's 12 so probably light enough recoil and shoots like a laser
WSM cases have become hard to come by these days. Plus they are a true high pressure design with a large case head. Meaning more recoil (probably more than a hot loaded .243). Looking in the Hornaday manual, I see the velocity tobe similar to a .250AI with a 100 grain bullet, but with about 20% more recoil. (similar chamber pressures)
You can easilly load the 6BR to about 2750 with a 100 grain bullet (will actually go a little faster). They are known to shoot extremely well, and are also a very forgiving round. The 6XC is also known to be very accurate, and probably will approach the 2850 fps mark without too much trouble. The 6/250AI will do 3000 fps with a 105 grain bullet, but you start to build up pressure fast at those speeds. Nice thing about the 6BR is that you can get by with a fairly short barrel (22" would be fine) to help keep the weight down and also give you a much better off hand shooting balance.
One other round not mentioned, and is also a knowingly accurate round is the 6x47 based off the .222mag case. It will push a 90 grain bullet to about 2700 fps, and with that small case had, have a lighter bolt thrust. Be one heck of a coyote round as well!