Original Remington 40-70

[labop]

What might be a good starting load for this rifle? It appears to have a paper patch chamber with a transition from the case mouth to the 8 groove rifling of about 0.280 in length tapering frm 0.436 to the groove diameter of 0.4075. Bore is about 0.402 with 1-18 twist. A double diameter bullet, bore diameter or groove diameter? Any possibility a GG bullet would work?

Thanks
labop

[George Babits]

Original load 70 grains of FFg probably and a 330 grain .403 diameter paper patched bullet; or a .409 grease groove. Try it and see what happens. They knew what they were doing 140 years ago and it still works fine now.

George

[labop]

I will get some PPDD bullets in 16-1 alloy. What hardness might work with the GG? I have a Hoch 335 flat nose GG bullet.

labop

[George Babits]

I have no idea what a PPDD bullet is so can't tell you anything there. If you want bullets to "bump up" probably better at 20:1. I use 16"1 on gas check bullets in a 38-55. My original 50-70-2 1/2 Sharps has a groove diameter of close to .415 or so. I had a mould made by Accurate Moulds of that diameter. I have been working with black powder on that rifle, but haven't gotten the right combination yet. One thing you didn't mention on that original Remington - - -is it a straight case or the bottle necked one?? Could make a big difference.

George

[beltfed]

George,
I think PPDD is for PaperPatchedDualDiameter, AKA: DDPP or DDEPP bullets : DualDiameterPaperPatched , or Dual DiameterEllipticalPaperPatched
bullets. Look, for example in the BACO catalog for : JIM403380E mold, designed for 16 twist 40s at 1.325" long. For Labop's orig 18 twist, I suggest
that bullet shortened slightly to about 1.25" long for full stability.
BACO can adjust the diameters for a person's particular chamber, Leade, FF case I.D.
These are working great in a number of people's rifles, particularly those that do not have a paper patch chamber.
beltfed/arnie

[desert deuce]

Had a Hepburn here for a short period of time in 40-70 Sharps Straight and a Roller in 40-70 Sharps Bottle Neck.
The 40-70 Sharps Straight Hepburn had an original 5 land and groove 18 twist barrel and shot the 385 grain Saeco bullet well with 1F Swiss.
FWIW I have the original Ideal 330 grain bullet for the 40-70 SS and it didn't shoot any better than the Saeco but should be a good hunting bullet.

[Geologist]

I have an original Remington 1 1/2 Rolling Block in 40-70 Remington (more or less the same as 40-70 Sharps BN) circa 1877 with a long free bore and lead and 22-twist. The 330 grain duel diameter paper patched has worked the best for me. The cartridge does require a wad stack. Thank you Kenny W.

[labop]

When I said DDPP that was Arnie's 403415E in a BA mold. As Arnie says that maybe too long for 1:18 twist. I think I will try that in 16:1 alloy but also take a few and machine the base off to his suggested over all length. I have a lathe with collet and length stop. That will still leave some of the larger diameter intact. In this really shallow rifling would a harder bullet work better? The rifling is sharp and smooth, no pitting. I really don't understand how any bullet could shoot well if bumped up to .436 and then swaged down to shoot through a 0.4075 groove. That bump up would have to be concentric with the axis of the bullet.
labop

[desert deuce]

"That bump up would have to be concentric with the axis of the bullet."

As in seating the loaded cartridge such that the ogive of the bullet fully engages the rifling?

[labop]

With base of the bullet in the case and the nose in the rifling I'm not sure the bullet would always bump up to fill the cone of airspace with perfect expansion. What would keep it from filling the bottom first, then sides and top? We are talking milliseconds but that could push the nose off center. These bullet alloys are not perfectly homogeneous, hard and soft spots just like brass cases.
labop

[desert deuce]

Won't know until you try.

[Geologist]

Take a look at Accurate mold 41-329-c and it casts like a dream. It works for my old Roller.

[labop]

Thanks I didn't know Accurate made a paper patch mold dual diameter.

[bruce m]

be aware that the 40/70 straight sharps was also called the 40/65 by other makers.
it was considered an idiot proof mid range cartridge.
mot reading i have done suggests it was loaded with 20:1 alloy bullets.

[beltfed]

I find in several rifles, 40-65, 40-72 and 38-50 that
my DDEPP bullets in my 9+1 COWW/Lino , about 15 BHN
shoot very well. The "patch to FF case I.D. / leade" base band
does not have to bump up. It is already a good fit.
In traditional lead /tin, the 16+1 also is in that hardnest range and
works well.
beltfed/arnie