I was in the same boat last fall - my son was 12 and had an elk tag. I already had a Remington 700 BDL in a .243, with the length of pull reduced to 12 1/2"; but was a little apprehensive about the knock down of the .243. Found a 7MM Douglas blank for $65, turned it down to a #4 sporter, and chambered for 7MM-08. First load I tried with it shot MOA. 150 Swift Scirocco with a moderate charge of H-380 gave me a little over 2700 fps in the 25" barrel. A real little sweetheart to shot in terms of recoil.

He wound up shooting an elk in the neck at 230 yards. Didn't look like the bullet expanded very much, but it worked nonetheless. His second shot at about five feet went in the elk's mouth and was found later during butchering in the animal's hip. It did expand all the way to the base, but appears to have a lot penetration at the expense of a smaller wound channel - at least at these velocities.

I have since developed some loads for the 140 Nosler Ballistic Tip and the 140 Sierra Gameking, which both shoot around MOA as well. They should perform well at the more modest velocities of this caliber. Looking at the horsepower chart, I'm going to try to limit this caliber to 300 yards on elk.