The number on my 452 pb solid is 452-277-RF-BP6. It looks like the catalog number for the 454's is 454-280. I just weighed some from my first batch. 3/4 range lead and 1/4 WW came out between 288 and 289 gr. as cast. Not surprising since I'm using a softer alloy than the wheel weights used in the mold specs.
Anyone loaded these in 450 BM yet? I'll be using IMR 4227.