I found an old note in my 45-70 files that claims 36.5 grs IMR 3031, behind a 405-gr soft-cast slug, is good in a Springfield Trapdoor, Whoever passed this info along to me was using Dacron filler.
Can anyone confirm this load with personal experience? How was your accuracy?
Do lighter loads of 3031 have any merit in these old rifles?
Thanks.