45-70 load for Springfield TD

[Slugster]

I have been trying to work up a decent load for my 1873 (1884?) Springfield Trapdoor Carbine. Original barrel cut to 22" and restocked into a Montecarlo Rollover (Hideous, I assure nyou, but purchased it pre-butchered). I have had middling luck with it and feel like it will shoot better than 6" at 50 yds. Have used the Hornady .458 Cal 350 gr. S.P., Lee 320 gr RNFP, and an old Lyman 500 gr RNFP. Have been using 1/4 part Linotype to 3/4 parts pure lead with 50/50 Alox/beeswax lube. This does not lead the barrel, but I think this is where my accuracy problem lies. The barrel is mirror bright, lands and grooves are sharp. Slugs to .458", and have sized bullets to .459, and .460. There seems to be nothing mechanical causing inaccuracy.

I cast a quantity of 500 gr bullets of 20 to 1 lead to tin alloy today and will be using iMR 4198 and RX-7 to work up loads. My thoughts are that the harder bullet is not "bumping up" or that with a harder alloy I am getting gas blowby. Anyone have any thoughts on this or a powder reccomendation that would work. I have scanned all of my literature and checked my powder supply and this is what I have. Any assistance would be greatly appreciated. I'm going to scan the site to see if anything is extant per my troubles.

[Ithaca Gunner]

Get a copy of J.S. and Pat Wolf's book, ''Loading Cartridges For The Original .45-70 Springfield Rifle And Carbine''. While you're at it, get a LEE 405gr. hollow base mold, some black powder, and Winchester large rifle magnum primers. The book will show you what to do with your components.

[W.R.Buchanan]

Slugster: If you aren't getting any leading in the barrel there probably isn't any gas blow by.

I have had my best luck with loading the .45-70 with 5744 powder.

I would suggest obtaining a copy of Handloader #248 Aug 2007 that has the definitive article by Brian Pearce on loading the .45-70 from Mild to Wild.

It has groups of loads in all pressure ranges from Trapdoor to Marlin 1895, Winchester 1886, and Ruger #1 rifles at the top end with a variety of powders and bullets. You should be able to find something that will work better than what you are saying has been happening.

If it still doesn't shoot right, hang it up over your fireplace and get a new Marlin.

Randy

[LIMPINGJ]

http://castboolits.gunloads.com/showthread.php?190999-My-Trapdoor-Loads-Technique-and-Equipment

[smithnframe]

The carbine load was a 500 grain bullet over 55 grains of black powder!

[M-Tecs]

The carbine load used a 405 grain bullet. The 500 grain bullets came later for rifle usage.

http://cartridgecollector.net/45-70-government

[Nobade]

I spent a great deal of time with my Dad's trapdoor trying to get it to shoot really well. Eventually after much experimenting I decided a .450" pure lead 400 grain slick paper patched up to .461" with 15# green bar paper loaded over a duplex charge of 7.0gr Blue Dot and 55gr. FFg with a paper wad for compression and a .060" poly wad under the bullet gave near MOA accuracy, no first shot flyer, and no wiping needed for all day shooting. The mould was made by NOE but Accurate could make something similar for less money. As a bonus the old pitted barrel is getting better looking the more I shoot it due to being polished by the paper.

[missionary5155]

That is a similar route I would go.
Trapdoors can be plain "fat throated / chambered" with equally fat groove diameter.
Our first 84 shoots real good with a .464 cast. They are all different so do learn your carbines diameters.

[Slugster]

Thanks to all who have replied, your replies have given me much to ponder. I have been a subscriber to Handloader for a very long time and will have to dig out the Aug. 2007 #248 copy that ia sure to be in a box somewhere. Thank y'all very much. Don't know if I want to go blackpowder or not, but that would be more traditional.

[Larry Gibson]

http://castboolits.gunloads.com/showthread.php?190999-My-Trapdoor-Loads-Technique-and-Equipment

My advise.

[1Hawkeye]

If you have any unique in your supply try 13.0 grs with the cast 500 gr. That's what my uncut early 84 likes and will keep them in about a 2" group at 100 yds. Trapdoor normally shoot 3" or less at 100 depending on the bore conditions. Have you checked the bedding on your stock and how the barrel is held in that could be the problem rather than the load your using.

[Ithaca Gunner]

Slugster, black powder and the LEE 405gr. hollow base bullet have some advantages with a Springfield in that the combination will chamber easily and bump up to fill the grooves provided they're cast of the proper soft alloy. The problem with loading groove size+ boolits is many times they don't chamber easily or sometimes not at all. I've never thought clean up was bad at all, I washed the cases in a net bag in the washer. Lyman's #39 Manual gives a duplex load for the .45-70 of, 7-8gr. of SR4759 and filling the case to the bullet with black powder for cleaner burning. I've found 10% Unique under the black powder charge works as well, (5gr. unique under 50gr. black for a carbine load). A 1-40 tin/lead alloy should be used with the LEE 405gr. hollow base mold.


When I posted I had forgotten about Larry Gibson's post on loading for the ''Trap Door'' however it's a good condensation of Wolf's book on loading for it.

[W.R.Buchanan]

Thanks to all who have replied, your replies have given me much to ponder. I have been a subscriber to Handloader for a very long time and will have to dig out the Aug. 2007 #248 copy that ia sure to be in a box somewhere. Thank y'all very much. Don't know if I want to go blackpowder or not, but that would be more traditional.

This might help: Randy

[Winger Ed.]

If there is a concern about the boolit 'bumping up', as soft of an alloy as you can get away with not leading should help it along.
I keep my 405s for the Marlin down to about 1300 fps or so, and my rather soft alloy does fine in all respects.

Many people want to use Lyman #2 or something pretty hard for everything, but ya really don't have to at slower speeds.
Also, yours might be a good situation for powder coating a softer boolit after sizing too.

[jeronimo41]

put about 68 grains in that load and the 500 will shoot !

[Wayne Smith]

68 grains of FFG, 20-1 or softer boolit, and it will hurt at both ends with that metal buttplate with the 457125 - 520 grains of hurt.