Black powder in solid head cases 2.0

[robert12345]

I hate to beat a dead horse , but have another question about black powder in the 45/70.

Rifle is; New,Marlin 1895, 45/70, Ballard rifling, 22 in bbl.
Powder is 10 pounds of GEOX 2f, ..been sitting around for 25 years.
Bullet is the 330 gr.,Gould HP.
.
In my collection, I have a few old Lyman reload manuals, and in a dark corner of one, is a note which says a reloader can use 10 grains 4759; then Black powder on top for a duplex load.

Q:
Has anyone tried this duplex load ?

Q:
Bullet lube ? .......I have on hand a mix of bee wax, and Neet's foot oil. ( It's a good lip balm, and a great boot grease. )

Q:
Primer,,, large rifle, or large pistol ? ..........I know in the old days, the mercury primer had a very weak flame.

Q:
Velocity of this duplex load ?

Q:
Bullet alloy in lead/tin, due to a likely higher velocity ?

Note:
For an over powder wad, I will be using the paper from a summer's old hornet nest.

Years ago, an old gun writer (Sam Fadala) used to recommend "hornet nest" for muzzle loaders; to separate the patch from the burning powder's flame front.
I used hornet nest "paper" often in my friend's .54 with RB, and it worked...good ! The patches were recovered very clean, and the bore stayed clear of BP fouling...

[Lead pot]

A 10gr duplex load of 4759 for a 45-70 is a pretty hot load I would think. That is a 14.2% if you use 70 grains of black. I hope your still around to tell us how good it worked.

[M-Tecs]

http://www.assra.com/cgi-bin/yabb/YaBB.pl?num=1233014429

[hpbear101]

M-Tecs link is spot on for duplex loading from my experiences. I have loaded duplex in the past for my 1886's and it is safe (IMHO), but I do not use them in Trapdoors. Why are you wanting to duplex? If it is to reduce fouling it does help, so does a good lube and breath tube. If you are concerned about the reduced capacity of solid head brass over balloon head brass it is not that big of a deal. I use GOEX Cartridge and have tried several loads with that very bullet. A lightly compressed 62 grains with a fiber or plastic wad has been my most accurate, I've used up to 68 grains (drop tube and more compression) and doesn't seem to be quite as accurate, any of them are accurate enough for hunting. BP is such an inefficient propellant that a few grains here and there isn't going to make a big difference in velocity. Issues like a good lube, and a good wad will likely have more of an impact than a few grains of powder.