I was just playing around with some BH 209 in my 45-90. I am trying to reload some 535gn postels, and found that with the bullet seated where I prefer it against the lands (c.o.l. 3.55) I have about 3/8ths of an inch air space in the cartridge. I have a Mirocu Winchester 1885 with 34 inch barrel. I am wondering if anyone else has ran up against this, and what they used to fill the gap.
Not really wanting to stir the purist pot, just experimenting with my rifle.