doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com black powder shotgun velocities

I first read about this in a series of articles on firearms propellants published by the American Rifleman, back when it was still a Shooter's Mag. As I recall one of the major factors was the Charcoal used. Willow was one of the preferred woods for Charcoal for powder. There was another which was higher regarded but was native to the UK I believe & I forget its name now.

In those days powder makers & made, or had made, charcoal to their specs. I highly suspect that many "Modern" makers of black powder simply use commercially produced hardwood charcoal. Yes it will go bang & put out smoke, but it doesn't reach the peak of that made a century ago.

Look at the velocity specs put out for the 1873 models of .45 Colt & the .45-70 Springfield by the U S Army. Even admitting that today we have solid head cases rather than the old balloon head cases which were used originally & held a tad more powder, the original velocities simply cannot be reached with present day Black.

The old standard 3-1 1/8 12 gauge load gave about 1200 fps @ 15 feet. This is generally un-obtainable with modern powder unless a heavier charge is used. Never-the-less I have always loaded by the equal volume method for shotguns & had satisfactory performance. Volume for 1 1/8 oz of shot will give about 2 13/16 drams of black or 77 grains rather than the 3 dram load of 82 grains. "IF" one points the gun right it will still kill reliably but is not equal in power to the old original loads.

Re velocity, I pulled out an old (1990) copy of The Complete Black Powder Handbook by Sam Fadala, and he says on pg 192:
"My 12 gauge mentioned above loaded with 1-1/2 ounces of shot and 100 grains volume of FFg blackpowder or RS Pyrodex gains a muzzle velocity of close to 1200 fps." Later in that paragraph he says that dropping the shot charge to 1-1/4 oz adds about 100 fps to velocity. Sounds just like a modern nitro load of 1-1/4 oz. He used an Oehler Model 35P proof chronograph, as described on page 50.

3 5/8 drams = 99 grains. 3 3/4 drams = 102.5 grains. Did he state what brand of powder he was using. Data in a Lyman Black Powder handbook did not meet these figures, but were slower.

A modern day 3 3/4 DE-1� oz load is supposed to give about 1330 fps, so this is indeed right in the same range. Some would depend of course on the exact placement of the screens which would vary the velocity a bit if at a different distance from the muzzle.

I did not see his chrono setup for shotguns, but I think he used 15 ft for his muzzle loading rifles. I did not see any specific brand recommendations for BP, but Fadala likes only FFg or Pyrodex for shotguns. His book concentrates on rifles and pistols. I thought I had a Lyman BP book, but no idea where it is.

Pyrotechnicians make much of their blackpowder and conduct contests to see whose is the strongest or best for various effects. In the forum I am on, charcoal seems to be the key and many woods and methods to char them have been tried. Of course milling, corning, glazing, and screening are also important.

When I was a serious competitor in m/l rifle competition I screened every bit of the black I used in matches. I had two screens that it went through. One sifted out the very large kernels by not letting them pass through. Then I took what passed through and sifted it through another finer mesh that allowed the fines to pass through and retained the "medium" sized particles. The very coarse stuff was used for in my shotgun, the very fine was either discarded or given to someone who shot flint. I got very consistent velocities with this sifted powder, usually Dupont GOEX. I have a 14 lb., .45 cal. roundball longrifle (buffalo gun, for those of you who know what that is), that I built, that will shoot 5/8" five shot groups at 100 yds. on a good day. I attribute part of that to the sifted powder.


Screening by the user, for a shotgun, is worse than useless, IMO. It's a total waste of time. I do understand that the poster was referring to screening at the manufacturing facility, before packaging and shipping, but in reality they do not do a very good job of it. There are particles of extremely varying size in a can of black.

SRH

No I was posting about amateur fireworks makers. But yes, the steps are important for commercial operations as well. Blackpowder is to pyrotechnicians what flour is to bakers.

In my Lyman BP Handbook for 12ga, fiber wads, 2F powder:
3.75 Drams, 1oz/shot- 1422fps
same but 1 1/8oz - 1355fps
same but 1 1/4oz - 1250
same but 1 1/2oz - 1100
Strangely enough if plastic wads were used velocities fell. Go figure that if plastic wads seal better there should be higher velocities - at least I think. Better stop doing that.

Example from a pyro site:

The balsa burned at 0.98 seconds (average of 3 sample tests) in the 12" timing trough and the Paulownia beat it out at 0.82 seconds average per foot. All batches identical except for charcoal. Should make some dandy black match or burst.

Pawlonia is often mentioned as a good wood to char for BP.

Paul;
Note the 1250 fps given in the Lyman book is 94% of the normally stated 1330 fps for a 3 3/4 DE - 1� oz load. This does not of course mean that modern day Black Powders are Bad, just they they often do not quite reach the potential of those from a century ago.

I can offer no explanation as to why the velocity fell with plastic wads. I am old enough that I began reloading in card & fiber days. In those days loads were simply listed as X grains of a given power for Y oz of shot. Hull brand or primer was not listed, other than back then R/P hulls used a different size than the 209 everyone else used.

When plastic obturating wads came on the market we were simply advised to reduce powder charge by 10%. It was several years before loads began to be listed by Specific components.

Black Powder does have the unique quality of burning at essentially the same rate regardless of outside influnces so I doubt this 10% reduction would apply with Black. Plastic wads are not generally recommended for use with Black as its higher temps tend to melt the plastic which can cause a sticky mess in the bore. Perhaps something related to this caused the lower velocities.