Question on a 308 load not in my book

[lead-1]

I have a question about a load for .308 that is not in any book I have. A friend of mine has some 308 rounds loaded with a 170 grain cast, spire point boolit w/gas check and 15.5 grains of IMR-4759 and no filler.
Is that a safe charge for that round? He has it showing 1400+ FPS but volume wise that sounds light to me.

[stubshaft]

I've gone in excess of 27.0 gr of 4759 with no pressure problems. It is not a position sensitive powder and exhibits no bad tendencies when downloaded. It IS a light load but should be perfectly safe.

[lead-1]

Thanks for the input stubshaft, I thought he was in for some teardown work but now I'll tell him it should be OK.

[Larry Gibson]

It should be ok but a faster burning powder such as Unique for use w/o a filler would be better for a 1400 fps load. That is kind of the bottom end for 4759 and it may not reach a psi to burn efficiently and give inconsistent ignition and accuracy. He will probably get best results with the load he's got by raising the muzzle before each shot to settle the powder at the rear of the case against the flash hole.

Larry Gibson

[leadman]

If the load is not consistent he can also go up a few grains and it might clean up. I use 19grs of SR4759 with a 170gr boolit in the 30-06 with excellent results. Also 12grs of Unique will work well for him.

[lead-1]

Thanks guys, I think before its all said and done I will try to find what boolit he is using. It looks like an M2 style bullet.
Maybe a 311329 boolit, I'm going to pull one down to see the actual profile and weight.