Shinz,

I can get 2400 fps with a 400 gr. bullet in the Taylor but I can't get the bullet seated down to the cannalure. As such, the bullet sticks out of the case a bit, but it doesn't matter. As the rifle recoils, the bullets hit the front of the magazine box and hence the bullet isn't going anywhere since the powder is quite compressed to begin with.

There is a simple way of estimating bullet velocities for different bullet weights. I have never seen it "published" anywhere but it will get you in the ball park.

Making the assumption that the cartridge case holds so much energy the muzzle energy of different weight bullets will be approximately the same. The heavier the bullet the less powder is typically used, but for estimating velocities one can assume the same powder charge and hence the same amount of chemical energy.

In the csse of a 400 gr. bullet in the 416 Rem. at 2400 fps, the vel. of a 450 gr. bullet is found from equating muzzle energies,

(400)(2400)^2 = (450)(V)^2

V = 2262 fps.

Hence, I would expect to get about 2250 fps for a 450 gr. bullet in the 416 RM.

If you do this for the loads in a reloading manual or in the ammo manufacturer's catalogs you will see this to be true.