Smokeless powder loads for 56/50

[Cannonman1]

Has anyone used Tight Group powder in a 56/50??  I have a bunch and would like to work up a load for my Spencer. I use it in my .45 Long Colt and .44/40 cartridges and it is an accurate powder.

[El Supremo]

This can be a sensitive topic, Cannonman:

Some here have shared smokeless loads that they maintain do not create harmful pressures.  Perhaps a SEARCH will surface them.

BUT KNOW that Winchester, in published data, shared that as little as 10% smokeless substituted for traditional black to achieve the same shotshell VELOCITY, DOUBLED PRESSURES.

Late addition on 12Jul18:
Forgot one other reason, namely ORIGINAL 1865 Spencers and post-war conversions had THINNER sidewalls than 1860's, that contributed to CRACKS in the rear corners of the frame where the top block "seats".  Larry Romano has encountered a few with this damage and they were fired with SMOKELESS loads when converted to use 44-40 and 45 Long Colt SMOKELESS loads that were THOUGHT to be ok for older black powder era revolvers such as the 1873 Colt Peacemaker. Original Spencers were not constructed from much stronger, modern materials.

If you are using a modern reproduction, ask the manufacturer and if you are assured smokeless is approved, try and get the person to share an "approved" load.  NONE of my friends that have asked Taylors/Chiappa can get a useful answer about safe smokeless HAND-loads! 

This is just my years of experience researching, chronographing and pressure testing.
Safety first.  Don't practice anything you can only do wrong, ONCE. 

I have owned and used both a Modern Bond "crusher" and Oehler 43 Personal Ballistics Lab to measure "pressure" of black, semi-smokeless and smokeless loads. In the 1980's, I could not find anyone at H.P.White that could correlate LEAD UNITS AND COPPER UNITS.  Most BP and many cast handgun pressures are in LUP's, whereas others are in CUP's.  I would be ESPECIALLY interested to have those sharing black = smokeless pressure loads provide references for pressure COMPARISON.  Unique powder is a HOT one with a steep pressure curve versus black.  The STEEPNESS of the pressure CURVE matters in comparisons.  Mere comparable velocity for bullet weight is only part of the story. 

Having been called to a morgue to identify what was stuck in the middle of one fellow's brain, a breechplug from using smokeless in a black powder firearm, left a lasting impression.

By the way, the head engineer for a large American maker of muzzle loading BLACK POWDER rifles, told me that they were deluged with liability claims by WIDOWS of the shooters.  Seems the claims were for faulty design.  Well ...... the manufacturer HAD a chemical/ metallurgical test procedure that was COURT ACCEPTED AS AUTHORITATIVE. 
It identified when smokeless had been shot.  When lawsuits were filed, the company's counsel shared info about the test, asked that the rifle be submitted and added that IF the test disclosed the use of smokeless, the claimant would be counter sued with vigor!  Funny thing, those claims stopped dead in their tracks when the ATTORNEYS realized no MONEY!
I was involved in two of these. Also involved with liability cases involving smokeless in break-open shotguns with percussion plugs.  No claimant won when smokeless was used!

Respectfully, especially to those who are comfortable with smokeless loads in Spencers.
El Supremo/Kevin Tinny

[Jack Wagon]

I think that is a very good answer El Supremo. I am also a fan of titegroup in guns of modern manufacture, but would not consider it for my Spencer. The only modern powders I have used in my Spencers are APP and Black MZ.  Jw

[Cannonman1]

Absolutely agree.. My 56/50 caliber Spencer is a Chiappa and is rated for smokeless.. Cowboy Action load (Tight Group )for my 45 Long Colt is at 6 grains .. Basically the same for .44/40..  These are used Chiappa Spencer and a Uberti Henry
Based on your information I think triple 7 or FFG Goex will be my choice for this caliber ( 56/50 ). Unless I have documented loading data that is safe and reliable, I won't go there.
Thanks again
Bill

[PvtGreg]

Try 8gr of TrailBoss under a thin cardboard wad and a 350r Bullet.  I have some old posts from a couple of years ago on this forum that includes target pics.  This is a good 100yrd load for a 56-50 in the Chiappia.

Pvt Greg

[mgmradio]

I use 9.5g of Unique for my 56-50 rifle. Very accurate out as far as I can shoot.