in trying out some bullets from a new mold mp's 432640 gc, I got a good load with 20 grains 4227, but as 4227 is it leaves a lot of powder in the barrel.
yesterday I thought maybe I'll try some 300mp since I have a bunch of it. I referred to Brian Pierces nov 2011 work in handloader mag, since ive had good success with 358156 in 357 mag 17gr 300mp.
the bullets I'm casting are 275gr solids and hollow points ranging from 255 to 265 grains.
Brian starts 250 gr cast load with 24gr 300mp, but both 270gr and 300 grain jacketed bullets his starting load is 20 gr 300mp.
I tried one 275gr solid yesterday in the marlin at 20gr and had noticeable flattened Winchester primer but no sticky extraction. I'm thinking to back off to 19 gr powder.
am I on the right track here.