Cast Boolets ans Surplus Powder for 45/70

[ohshooter]

Checking through some of my reloading data, I saw that I had prints outs from the "old" cast bullet forum for loads using surplus powder. I didn't find one for the 45/70. The bullets are Lee 457-340 and 457-405, the rifle is a Marlin 1895 SS. I'm looking for opinions and/or loads for the surplus powder. I have a good range of the surplus from NM-04 (fastest) to WC 860 PD (slowest). I'm planning on using this for Ohio deer this year.

[5Shot]

WC844 would be my pick. My 45-70 likes a full charge of H335 and a 437gr Hard Cast. I shot a group with 3 shots touching (it's a Ruger #1). Hodgdon lists this load under the Marlin/#1 secton.

[9.3X62AL]

One surplus powder load I have used successfully and accurately in the 45-70s (Ruger #1 and Marlin 1895) involves duplexing, which some folks frown upon. Using the Lee 405 grain RN bullet, I first drop 6.0 grains of IMR-4198 into the case, followed by 48.0 grains of WC-860. The bullet is seated to give very slight compression to the powder column in the interest of keeping the "initiator" (4198) close to the primer and the s-l-o-w 860 atop the faster fuel. Results have been 1873-level ballistics (1300-1325 FPS), 1-1/4" groups at 100 yards/aperture irons, and complete consumption of the slow powder without unburned powder kernels in the rifle's bore and eventually in its action. I started with 100% density 860 solo under this bullet and some heavier numbers, and they all left bore trash in their wake--even the 560 grain Mastodon Flattener #462560. (Surprisingly, that long bullet flew true in the #1's 1-20" twist.......#462560 was meant for the 458 Win Mag and 460 Weatherby that use 1-12" to 1-14" twist rates, for whatever that factoid might be worth). I went about the duplexing slowly, first using 4198/860 in a 2.0/52.0 ratio as above, then 4.0/50.0, and at 6.0/48.0 got old school ballistics and a trash-free bore. I have run these loads for close to 20 years, and they do no more damage to brass than do other conventionally-loaded 45-70 ammunition......by that, I mean that at 10-12 firings I start getting case burn-throughs at the point where the bullet base rests inside the case when seated and subsequently fired. Kinda reminds me of the old paper-hull shotshells in that respect.