70gr FFg Fills A .45-70 Case; Too Much Compression?

[Nobade]

I've loaded many a Winchester, Federal and Remington 45-70 cases with 70 gr of GOEX FFg, FFFg and Cartridge BP to replicate the M1873 and M1882 service loads. I don't use a drop tube, just throw the charge with a Lyman 55, Then a compression die (Lee expander die body with a flat faced plug) is used to compress the powder to the seating depth of of the bullet.

Yes, the powder is compressed into a solid mass as was the BP in the original service loads. The original 45-70 service rounds were not "balloon heads" but were inside primed with a Benet inside primer. Their capacity is very similar to Winchester cases. With such loads a strong magnum level primer is best to use. For complete information refer to Wolf Spence's book on replicating service 45-70 loads or my posts in;

https://castboolits.gunloads.com/sho...-and-Equipment

That is a very good book to read and really got me started with the Trapdoor rifle. And about the only place I have seen that explains how to use the Buffington sight.

[GregLaROCHE]

With the right tools it is no problem to duplicate the original trapdoor load using 70 gr 2f Swiss and the Lee 458-405-HB. A drop tube and compression die will set the powder height right where it needs to be. And no, the trapdoor does not have a throat at all, just a bevel on the start of the rifling just like the SAAMI 45-70 chamber does.

My normal 45-70 paper patch loads use 81 grains of 1.5F and that fits in Starline cases with .100" to spare by using a drop tube.

Maybe I need to try my drop tube again and try it with some Swiss powder. What was the overall length of those boolits?

[Milky Duck]

try poking the BP in through your funnel with a thin solid plastic rod...just keep poking it around and IT WILL FIT...if I can get 65grns of my non compressed homemade stuff...surely manufactured stuff will fit easier.

[FrankJD]

In fire formed Starline .45-70 brass I can 31" drop fill to the rim with 82 grains of Swiss 1-1/2F, push in a .060" LDPE wad, compress to .1", taper crimp in the PPB.

[Edward]

In fire formed Starline .45-70 brass I can 31" drop fill to the rim with 82 grains of Swiss 1-1/2F, push in a .060" LDPE wad, compress to .1", taper crimp in the PPB.

I do it too with O E 1 1/2 no problem ,he taught me ! /Ed

[craneman]

My match load is 83 gr Swiss 1.5 under a paper patch bullet. Slow poured through a 30" drop tube leaves enough room to seat a .060 ldpe wad then compress .080.
Fits easy and shoots well!
Todd

[John in PA]

Old balloon-head cases held 70 grains. Modern solid-head cases hold 55 grains, the carbine load.

I would have to disagree. The balloon head alters capacity by 3-4 grains max., easily overcome by use of a drop tube and compression die.

[Carrier]

I’ve had no issue getting 70 grains in a Winchester case loading as in Spencer’s book with either a 405 HB or 500 grain bullet. My 1873 trapdoor does have better accuracy with 60 to 65 grains of 2f.

[FrankJD]

There will be an interior volume difference between new, sized brass and fire formed brass, as well as different brand brass.

New brass gets annealed and loaded as is in order to fire form. Fire formed brass is for load development and matches, and it will take a larger charge of powder.

[Larry Gibson]

Keep in mind the original Government 45-70 load using 70 gr of "musket powder" was not loaded into balloon head cases. They were folde copper, then brass cases with an inside Benet' primer. The 70 gr charge was heavily compressed into a solid piece. Burns much more efficiently that way. Winchester cases have very close to the same internal capacity as the Benet' primed original 45-70 cases.

[M-Tecs]

Keep in mind the original Government 45-70 load using 70 gr of "musket powder" was not loaded into balloon head cases. They were folde copper, then brass cases with an inside Benet' primer. The 70 gr charge was heavily compressed into a solid piece. Burns much more efficiently that way. Winchester cases have very close to the same internal capacity as the Benet' primed original 45-70 cases.

That is an often overlook part of the equation. I have a fired one of those in my collection but it is in rough shape. It was found at Fort Snelling in St. Paul during some cable trenching.

The question that I have is with that much compression how is the burn rate effected since the powder is being crushed? I only dabble at BPCR but over compression has not been good for me in respect to accuracy.

[Winger Ed.]

I load a few just for the novelty of them. Not enough to get properly set up though.
I dump the charge through a regular powder funnel, then hold it onto the case mouth with one hand and thump it 5-6 times.
It settles on down into my RP brass.

[Road_Clam]

There is no for me to jam 70g of Goex 2f into a modern commercial case and achieve a needed seating depth of the typical 405 rnfp bullet . Ive tried a drop tube ive tried vibratory methods to help powder settling and bottom line in my experiences i can get about 65gr max and thats using a LOT of compression force .

[freakonaleash]

I just loaded some 45-70 yesterday. Easily able to get 68 grains in the case using 1997 vintage Goex 2FF and a 24" drop tube. Put a .030 wad on top then used the bullet to compress the load 1 band's worth to get it to the crimp groove. Really very little compression and no bullet deformation. Bullet was cast from 20-1. We'll see how they shoot today.

[2manyguns]

yrs back black powder was measured by volume rather than weight,,has that changed ??

[Don McDowell]

The only change is the internet myth about blackpowder being measured in volume... Read the old books, it's always been in grains or drams..

[Kenny Wasserburger]

Don you said a mouthful there old friend. A lot of Bad info in this thread. Some from folks that can’t make BP Shoot accurately. Yet pontificate like some world class marksman.

KW

[FrankJD]

For cartridge guns, BP is always weighed ... for traditional muzzleloaders, BP is (almost) always volume charged. YMMV, but it shouldn't.

[longbow]

I have little knowledge of this subject but if I may I'd like to ask a question... if the powder is compressed to a near solid lump, what difference does granulation make? Why would FFg be preferrable to FFFg?

As Larry points out in post #30 the powder was compressed to a solid piece. I have to think that FFg granules are crushed in that process.

Please enlighten me!

Thanks,
Longbow

[FrankJD]

Let the gun decide the compression to employ. You may find out that ya don't need to make solid cakes of BP in the brass. That's what load development is all about. Coarser powder introduces a tad more air into the mix.