Today, I loaded up some 2400(22.0, 22.5, 23.0, 23.5 and 24.0gr) and dacron batting under a 300gr saeco fn gc in my 444 marlin. I know that I use 25.5gr of 2400 and a tuft of dacron under a 280gr wfn gc and it WILL kill deer under 100 or so yards. I am wishing that they go around 1500-1600fps but I'd take accuracy over fps anyday. I'll have to wait to chrony it( i shot the chrony). i know it will be light-medium "kicking" round but that what I want it to be. I have about 12-13lbs of 2400, so I'll use it in my 444. My 444 is a tc encore and 24" MGM barrel(1 in 20" twist). I'm guessing that 24 or 25 gr of 2400 under 300gr boolit is good enough pressure-wise(psi). I have shot 22.0gr of 2400 with a tuft of dacron under a 300gr boolit and the cases looked good. There was no primer being pushed out, cratering....and I was pleased that there was no powder residue left on the outside of the cases. there was no dacron left too. I looked inside of the barrel and found it clean and "ring"less. It "kicked" about as much as a 243 will.
Now if the weather co-operates(which it won't), I'll shoot some groups.