Since Lil Gun & H110 are rare as truth from the White House, I spent some time looking at my powder inventory. WOW ! 5 pounds of IMR 4198. (My 222R favorite)
The general lack of "official loading data" for the 450BM extends to 4198 ..... but reposing in my safe is a S&W 460 Magnum.
Lots of data for it from Hodgdon. With a 325 gr bullet and 41 gr of 4198 it gave 1695 fps from a 10.743" barrel. I made up a dummy 450 BM with the 300 gr Lee GC and 40 gr of 4198. Feeds and chabers perfectly. My BM has a 20" tube, so IMO, I could back down the load and still get the velocity I want. Although the 460 case is a tad longer, the need to seat so much deeper than the 450 avoids any powder compression issues.
When I bought the 4198, I really didn't need it as a pound lasts forever in a 222. Message is: buy any powder you can.
Just bought 3 pounds of 4320 at the local hardware. It's a powder that gets no respect but will keep your 243 to 35 Whelen running when the shelf get bare.
Anyone else have experience with 4198 in the 450 ?
Thanks.