The pressure peak of a black powder discharge is at the front of the time continuum. Smokeless powder discharges build to a peak pressure limit more slowly, which is why they are sometimes called "progressive" powders. This also explains why we often see pictures of smokeless powder damage to black powder guns with the damage down on the barrel rather than at the breech. A Pyrodex discharge peak would be between the black powder and smokeless peaks on the time continuum.
I want to thank the readers who quickly pointed out my user headspace error. I apologize for the mistake. Now, this month lets look at some Pyrodex loads for skirmishing, and their suitability for target shooting.
Please also note, I am not advocating the use of Pyrodex as an approved Skirmishing propellant, and, conversely, I am not advocating banning Pyrodex for the same purpose. What I wanted to do is review what Pyrodex is, how it can be used, and then let the reader make his own informed decision.
A Pyrodex load behind an identical projectile as used for your regular blackpowder load will generate what can be perceived as more recoil, but not significantly more. I noticed the recoil increase in the musket, where I was pushing a 500 grain bullet out of a ten-pound Harper's Ferry Three Bander. In the Henry, where the bullet weighs half of the Minie Ball (and the Henry weighs more than my musket), the recoil seemed about the same. The recoil in the Smith Carbine and my pistols was also not noticeably higher with Pyrodex. From the recoil standpoint, Pyrodex and Black Powder are about the same until you get into the large caliber slugs, and then the increase is nominal. Most of the time, I was shooting from a bench, which always increases felt recoil. An offhand shooter may not notice the increased recoil at all.
One thing I did notice was that my Pyrodex groups in the Smith and Henry were very close to those I get with my Black Powder loads. I even got one group better than the black powder Smith loads, which I found encouraging for applications outside of N-SSA competitions. This test was a bench test, though, and the Smith was also the only firearm that exhibited noticeable hang fires with the Pyrodex propellant. As I mentioned last month, Pyrodex ignites at a much higher temperature than black powder, and that requirement, combined with the long primer communication channel and two turns in that channel resulted in hang fires more than half the time. A steady bench helps eliminate the effect of the hang fires, however, we all know the N-SSA is not a bench shooting competition. Since N-SSA rules prohibit duplex loads of any kind, using FFF or FFFF powder in the back of the Smith cartridge is out of the question.
|
firearm |
load |
bullet |
BP Velocity |
Pyrodex Velocity |
|
M1855 Musket |
60 grain or equivalent |
Ball Accuracy .580 450 gr |
688.3 fps |
781.4 fps |
|
Smith Carbine |
25 grain or equivalent |
Ball Accuracy .517 350gr |
684.2 fps |
751.5 fps |
Henry Rifle |
30 grain or equivalent |
NSK .452 RNFP 250 gr |
893.8 fps |
1090 fps |
M1858 Remington |
18 grain or equivalent |
Speer RndBl .454 141 gr |
553.2 fps |
510.4 fps |
I actually liked the Pyrodex best in the Smith and Henry applications. In the Henry, with magnum primers, quick ignition was delivered routinely. The internal ballistics seemed identical in the Henry, and Pyrodex results were on a par with the black powder, with the noticeable exception that velocities in the Smith and Henry with charges of equal volume of black powder and Pyrodex always resulted in higher velocities for the Pyrodex loads.
I had inconsistent results with the Remington pistol. I was using a reduced load, and it may be that you need to use more Pyrodex to get consistent results. The Musket test also resulted in higher velocities for Pyrodex, but the group for black powder was more consistent. Further testing of the musket and pistol may result in more refined data.
For cleaning Henry cases after Pyrodex use, I just soak them for ten minutes in a vinegar bath to neutralize the residues. Cases can then be prepped as usual for Henry. Be careful not to get any of the vinegar solution on blued firearms, as it can cause severe spotting of the finish.
Pyrodex certainly has its place in historical shooting. I use it in shotgun as well as Civil War firearms. Whether or not it is suitable for skirmishing is a decision out of our hands. Personally, I wouldn't use it in original black powder firearms, but do use it in modern replicas. I think the use of Pyrodex can be successful, but is up to the individual where Pyrodex is an allowed propellant. I hope you enjoyed learning about Pyrodex as much as I did.
Until the next time, promote responsible gun ownership, shoot safe and have fun.