Actually it would cost you some velocity, but not as much as you might think. I have a Savage with a 22" barrel and a Arisaka with a 19" barrel, and using the same cartridges (.260s) they are less that 75 fps apart. Still I think the 16.5" barrel would be best suited to be a saddle carbine, that's just a little better than the .30-30. As for the scope, it is a specialty job for use on what is tremed a scout rifle. A thing dreamed up by a great pistollero. You could mount a normal scope on it if you wanted.