I took my Jeffery 450/400 with 24 barrels to the range yesterday to work on load development.

I tried some of the new Hornady 400 ammo. Great news is it put 4 shots, 2 rights and 2 lefts into one and a half inches at 50 yards to point of aim. Bad news, it was going 1800 fps.

I took one apart and the powder looks like H4831SC. The charge weighed 81.8grs. My load with the Woodleigh 400 gr bullet with H4831SC is 85-86grs @ 2,050 fps. I tried some of the Hornady 400gr bullets with 86 grs and got 2000fps and good regulation.

Temp was 40 degrees outside but at my range you shoot from a heated shooting house. I'd estimate the temp inside to have been in the 50s.