Mike Venturino tends to be a little unreasonable when it comes to smokeless in antiques. Once one understands the different burn rates of smokeless powder and their effect on peak pressure, one can make smokeless loads that have a lower peak pressure than BP and less chance of producing corrosion in the little pits that might not get cleaned out enough. I have shot smokeless in a wide variety of antique Winchesters for over ten years. If you want to keep it simple, using 5744 under a soft cast bullet in the original weight, in amounts producing original Black Powder Velocities, will duplicate BP ballistics but with a lower peak pressure than black powder, and it has enough bulk such that you will not be able to insert a double charge in a lot of the old cartridges. The only difficulty you may run into is that the lower peak pressure of 5744 may not be able to ‘bump up’ the soft cast bullet to fill the grooves. Although you can go with a slightly faster, and still safe, powder such as 2400, I prefer to address the problem by using soft cast bullets and sizing them larger. Also, if the pressure gets too low, you start getting soot on the outside of your cases, since they are not sealing against the chamber. For larger cases, such as 45-70 and 45-90, IMR 4198 works well (it can also work well in smaller cases as well). In general, I go for medium speed powders that produce a low extreme spread in velocities at original velocities. I find that 2400 often produces high extreme spreads in comparison with 5744, which produces the lowest extreme spreads of the powders I have used.

Here is an old post by John Kort …

No less authority than Winchester Repeating Arms Co., deemed that smokeless ammunition was fine for use in their toggle link 1873 Winchester with the introduction of their .44 W.C.F. smokeless cartridge in 1895. The cartridge boxes indicated that this ammunition was to be used in their models of 1873 and 1892.

U.M.C. introduced their .44-40 smokeless ammunition in 1896.

Their original smokeless .44 W.C.F. / .44-40 cartridges were loaded with DuPont No. 2, a bulk smokeless powder. 17 grs. by weight was the charge and filled the same powder space as 40 grains of black powder.

By the early 1900’s, “Sharpshooter” smokeless was used in 15 gr. charges. Sharpshooter was a dense smokeless powder, not too dissimilar in burning rate than today’s 2400. As a dense powder , there was airspace in the case.

The only problem I see with using smokeless powders in a toggle link action, is that if a faster burning powder is used (Bullseye, Unique, etc..) it is possible to accidentally double charge a case which would lead to a catastrophic failure such as the one reported by Scott T.

It is by far best to use smokeless powders whose burning rate is similar to the original smokeless loadings where a double charge could not be loaded into the case. Alliant has published data for Blue Dot & 2400 in the .44-40 at black powder pressure. A double charge of either of these powders would definitely be noticed. 4227, 4759 and 5744 are other powders where it would be almost impossible to double charge a case.

Regarding the issue where it is thought that smokeless stresses the action more than black powder, a noted ballistician has told me that it is the total pressure that the action is subjected to, NOT THE RATE at which it is applied. If it were at the rate at which the pressure is applied, then since b.p. will slug up an undersized lead bullet and smokeless will not, it would appear that there is a faster spike in b.p. pressure than smokeless (at the same pressure)..

I have an original 1873 Winchester made in 1882. I purchased it 6 years ago. I have fired close to 3,000 rounds of smokeless ammunition loaded with the above powders along with about 500 rounds of black powder cartridges. It is as tight today as it was when I purchased it.

REGARDING THE 1876 WINCHESTER

A search of old Winchester catalogs would indicate that they did not offer a smokeless option for the 1876 Winchester cartridges. The reason probably being that this model was discontinued after only being produced into the smokeless era by several years.

In similar cartridges like the .45-70, .45-90, 50-100 and .50-110, the earliest smokeless loadings used DuPont No.1. This was a bulk smokeless powder that was used in capacity loadings just like b.p. It weighed 40% of the b.p. charge. For example, in the .45-70, 70 grs. by weight of b.p. = 28 grs. by weight of DuPont No.1 which filled the same capacity.

Unfortunately, DuPont No. 1 is no longer available, having been discontinued in 1927. Today, 4198 will replicate the ballistic strength of DuPont No. 1 using the same charge, BY WEIGHT. Therefore, using a charge weight of 4198 that is 40% of the original b.p. charge will give similar velocities /pressures of the b.p. loading.

I would suggest starting at a 35% charge weight and adjust from there, based on the velocity you are getting as compared to the original ballistics. I would suggest using the square toilet paper to hold the powder in place. You could try it with and without the t.p. to see whatdifference there might be. AA5744 is slightly quicker than 4198 and is more adapted to cartridges with larger airspace. You could try that at 10% less than the 4198 charge weight and go from there.

At this point in time, there is no smokeless powder that will replicate b.p. ballistics / pressures in your .50-95 with a capacity loading. Even slow burning 4831, with a capacity load in the .45-70, will exceed b.p. pressure and velocity.

Have fun with your ’76.

w30wcf

Cat Creek said
Great information, thank you!  

Win38-55 has it going on….

Here is the original full context to his reply about John Kort’s quote. John is a .22wcf, .30wcf and .44wcf historian.