50 90 trapdoor loads

kraigwy · March 21, 2016, 11:12 AM

I'm thinking I would get better results here then the reloading section.

I'm in the process of getting a Springfield 50-70 Trapdoor (original). I want to shoot it but I don't want to use BP.

Anyone have any recommendations for a Low pressure load.

I'm looking at 5744 powder. According to Quick Load, 20 grs. of 5744 will give a 450 grn cast bullet 1060 fps with 8186 PSI.

But I don't know the max pressure on these old rifles.

For an ideal I use 32 gr of 5744 using 255 gr pistol bullets in my 45-70 trap door. Its pretty accurate at 1800 fps with 13K PSI.

But I heard the 50-70 Trap door needs a bit less pressure

Dufus · March 21, 2016, 05:51 PM

The Lyman Cast Bullet Handbook 4th Edition warns that the load data is for use in only newly manufactured rifles designed for smokeless powder and not the original designed for black powder.

I does list a 425 gr Lyman #515141 with 24.0 gr of 5744 with a velocity of 1137 fps and pressure of 14,100 CUP for the 50-70 Government.

I have a digital copy of an Accurate Powder manual from 2003 that I could email to you.

**Mike Irwin** · March 23, 2016, 12:53 PM

A .50-70...

What .50-70?

A Model 1866?

A Model 1868?

A Model 1870?

To be perfectly honest, I don't think I'd consider shooting any of the trapdoors with smokeless until the 1884 Model.

Hawg · March 23, 2016, 02:07 PM

Quote:

To be perfectly honest, I don't think I'd consider shooting any of the trapdoors with smokeless until the 1884 Model.

I know I wouldn't. Either use bp or hang it on a wall or sell it to somebody else.

Tidewater_Kid · March 23, 2016, 04:55 PM

If you can't get real black powder, I have used Pyrodex RS in 50-70 gov't cartridges with no issues. I have fired this in 1866 2nd Allin's and 1868 riles. I use 50 grains (by volume) and a fiber wad. Works great and not hard to clean up afterwards. Bit of hot tap water down the bore and rinse. Then clean like normal.

I use Goex 2F when I can get it.

TK

mehavey · March 23, 2016, 06:36 PM

Question 4 Kraigwy:

What's driving you away from a BP loading ?

kraigwy · March 23, 2016, 09:40 PM

mehavy:

This is gonna sound stupid, but I want shoot CMP matches with it, requiring 10 shots rapid fire in 80s. Don't know if its possible, but I want to try.

Its been my experience BP shoots best if the barrel is swabbed after about 3 rounds.

mapsjanhere · March 24, 2016, 08:41 AM

Not even saying what your fellow shooters think of you clouding the firing line with BP

Buzzcook · March 25, 2016, 09:47 PM

You might consider a black powder substitute like trail boss or pyrodex.

kraigwy · March 26, 2016, 10:21 AM

I like Trailboss for a lot of guns but I don't think I want it in this old rifle.

5744 developes half the pressure (8186 PSI) for the same velocity (1000 fps) as Trailboss's 17365 PSI.

Per Quick Load.

Its the pressure I want to keep down. 5744 works great in my '84 Springfield Trapdoor in 45-70 and my Remington Rolling block in 44-90 Sharps Bottleneck. Low pressure with moderate velocity (equaling BP loads).

Pyrodex puts out about as much smoke as BP which I'm trying to eliminate.

mehavey · March 26, 2016, 11:06 AM

Unfortunately, modern smokeless powders (incl 5744/a personal favorite) induce a much sharper pressure spike than BP.
If you are set on non-BP in a original BP gun, see if you can find some 4759. It more "approximates" the BP curve.

kraigwy · March 26, 2016, 12:19 PM

Mike:

Its a 1868 model, made in '69, 5 digit ser. # 51**

March 21, 2016, 11:12 AM	#1
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	50 90 trapdoor loads I'm thinking I would get better results here then the reloading section. I'm in the process of getting a Springfield 50-70 Trapdoor (original). I want to shoot it but I don't want to use BP. Anyone have any recommendations for a Low pressure load. I'm looking at 5744 powder. According to Quick Load, 20 grs. of 5744 will give a 450 grn cast bullet 1060 fps with 8186 PSI. But I don't know the max pressure on these old rifles. For an ideal I use 32 gr of 5744 using 255 gr pistol bullets in my 45-70 trap door. Its pretty accurate at 1800 fps with 13K PSI. But I heard the 50-70 Trap door needs a bit less pressure __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071

March 21, 2016, 05:51 PM	#2
Dufus Senior Member Join Date: December 10, 2014 Posts: 1,965	The Lyman Cast Bullet Handbook 4th Edition warns that the load data is for use in only newly manufactured rifles designed for smokeless powder and not the original designed for black powder. I does list a 425 gr Lyman #515141 with 24.0 gr of 5744 with a velocity of 1137 fps and pressure of 14,100 CUP for the 50-70 Government. I have a digital copy of an Accurate Powder manual from 2003 that I could email to you. Last edited by Dufus; March 21, 2016 at 06:02 PM.

March 23, 2016, 12:53 PM	#3
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	A .50-70... What .50-70? A Model 1866? A Model 1868? A Model 1870? To be perfectly honest, I don't think I'd consider shooting any of the trapdoors with smokeless until the 1884 Model. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

March 23, 2016, 09:40 PM	#7
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	mehavy: This is gonna sound stupid, but I want shoot CMP matches with it, requiring 10 shots rapid fire in 80s. Don't know if its possible, but I want to try. Its been my experience BP shoots best if the barrel is swabbed after about 3 rounds. __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071

March 24, 2016, 08:41 AM	#8
mapsjanhere Senior Member Join Date: August 6, 2009 Location: Albuquerque Posts: 2,832	Not even saying what your fellow shooters think of you clouding the firing line with BP __________________ I used to love being able to hit hard at 1000 yards. As I get older I find hitting a mini ram at 200 yards with the 22 oddly more satisfying.

March 23, 2016, 04:55 PM	#5
Tidewater_Kid Senior Member Join Date: July 3, 2005 Location: Alabama Posts: 925	If you can't get real black powder, I have used Pyrodex RS in 50-70 gov't cartridges with no issues. I have fired this in 1866 2nd Allin's and 1868 riles. I use 50 grains (by volume) and a fiber wad. Works great and not hard to clean up afterwards. Bit of hot tap water down the bore and rinse. Then clean like normal. I use Goex 2F when I can get it. TK

March 23, 2016, 06:36 PM	#6
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 6,885	Question 4 Kraigwy: What's driving you away from a BP loading ?

March 25, 2016, 09:47 PM	#9
Buzzcook Senior Member Join Date: November 29, 2007 Location: Everett, WA Posts: 6,126	You might consider a black powder substitute like trail boss or pyrodex.

March 26, 2016, 10:21 AM	#10
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	I like Trailboss for a lot of guns but I don't think I want it in this old rifle. 5744 developes half the pressure (8186 PSI) for the same velocity (1000 fps) as Trailboss's 17365 PSI. Per Quick Load. Its the pressure I want to keep down. 5744 works great in my '84 Springfield Trapdoor in 45-70 and my Remington Rolling block in 44-90 Sharps Bottleneck. Low pressure with moderate velocity (equaling BP loads). Pyrodex puts out about as much smoke as BP which I'm trying to eliminate. __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071

March 26, 2016, 11:06 AM	#11
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 6,885	Unfortunately, modern smokeless powders (incl 5744/a personal favorite) induce a much sharper pressure spike than BP. If you are set on non-BP in a original BP gun, see if you can find some 4759. It more "approximates" the BP curve.

March 26, 2016, 12:19 PM	#12
kraigwy Senior Member Join Date: June 16, 2008 Location: Wyoming Posts: 11,061	Mike: Its a 1868 model, made in '69, 5 digit ser. # 51** __________________ Kraig Stuart CPT USAR Ret USAMU Sniper School Distinguished Rifle Badge 1071