Pyrodex longevity

[BrownBear]

...but they used to have a caveat in the literature about Pyrodex having a finite shelf life.

I'm starting to think my own life span is more finite than Pyrodex. The stuff I have is right at 40 years old and still going. Might not be "forever" like black powder, but neither am I. :wink:

 

[Billnpatti]

Yep, I have some that is not as old as yours but still pretty old. I shot some about a year ago and it still went bang. I didn't chronograph it so I don't know if it has deteriorated since I last used it about 8 years ago. I don't know, only a fool argues against the facts so, faced with your experience, maybe the stuff doesn't deteriorate over time. :idunno: Oh well, I shoot only real black powder, with rare exception, so whether it actually does or doesn't deteriorate over time.........I truthfully don't know. I think it does but....... :idunno:

 

[BrownBear]

I used to chronograph it every few years, but after a small drop in the first 10 years, it quit dropping. And I got lazy and quit chronographing. Just too much folderol to put numbers on what I saw on paper, I guess. But no change in accuracy and no change in sight-in was enough to convince me the amount of loss was a non-issue.

My "mentality" about subs is driven by frontier living, I guess. While I prefer real black just cuzz, it's next to impossible to get way out here at the far end of the supply chain. Yet subs are easy to get. It's been my long-held belief that it would be foolish to swear off subs and leave myself vulnerable like that.

Anyone coming up this way to poke a critter is likely to discover the same thing the hard way. And they just better be skilled and experienced in using subs if they don't want to have wasted their investment in plane rides and guides.

 

[Louisk]

It's good to hear the stuff holds up for a while. If I get more summers like this last one my current powder supply is going to be around for a long time

 

[tenngun]

I got about a dozen pounds, I shoot them in my cap guns and I shoot them in my rifle on top of a 20 grain kicker charge. I don’t plan to replace it as it runs out, but I have not had trouble with it. But I clean deep. If you got it shoot it, if you can get the real stuff use it.

 

[BrownBear]

But I clean deep. If you got it shoot it, if you can get the real stuff use it.

That tosses it into a pretty good nutshell.

Heavy emphasis on the cleaning. If you don't clean well after shooting, it will raise cob with your steel. In my firsthand experience, Pyrodex fouling is much worse on steel than that from true black powder, and you have to work extra hard to get rid of it after every shooting session.

 

[coloradoclyde]

Of all the substitute powders, Pyrodex is the closest to real BP in every aspect. It is also the least likely to degrade of all the substitutes. Properly stored, Pryodex will likely outlast you.
If Pyrodex fails you, it is your fault... Not the powder's

 

[dlidster]

This string has really stirred my interest. I have a can of Pyrodex that I haven't opened in 40 years. I originally used it for cast bullet loads in a Winchester 1894 rifle that I really regret having sold when I was younger and dumber. This can has both "RS" and "Rifle and Shotgun" on the front of the label, but reads ""FFFG equivalent" on the back. I haven't used Pyrodex recently, but I believe Hodgdon now considers "RS" an FFG equivalent and "P" an FFFG equivalent.

But, to the point. I was curious to see how the 40-year-old Pyrodex compared to equivalent loads of Triple 7 and Black MZ I have on hand. I did not run the tests in my ML rifle. For the sake of expediency, I ran the tests in .38 Special cases with the powder loaded to the base of a 125 gr. bullet. The volume turned out to be about 18 gr. in my Traditions brass powder measure.

I set the measure by pouring the powder from a case filled to my satisfaction, then pressed the plunger till the powder was flush with the top and locked it. I used this measure setting to charge 15 cases, five of each getting Pyrodex, Triple 7, and Black MZ. I visually checked the cases to make certain the fills were uniform. I chronographed the loads fired from a Ruger Blackhawk with a 7½" barrel. The results are as follows:

Avg. Hi Lo Difference Hi/Lo
Pyrodex 538 645 443 202 37%
Triple 7 800 824 754 70 9%
Black MZ 717 824 662 162 22%

I realize the effective difference in charge uniformity would be less with 80 gr. or so loads, but I was just looking for an indication of what was going on. Since I haven't used recently manufactured Pyrodex to compare with T7 or BMZ, I don't know how its energy compares. For those who do, does current Pyrodex have significantly less energy than T7 or BMZ, or are we looking at degradation over time?

Or, is this just a mystery I'm going to have to live with?

 

[BrownBear]

That's a slower burning Pyrodex, and I'd expect it to perform less well than P in small quanities.
There's also the difference in "power" of the three powders. Trip Seven in particular recommends a 10% reduction in charge from other powders. Don't recall about BMZ, but it may have the same kind of recommendation, unless I'm mistaken.... Again. :wink:

Be interesting to compare P, and the Trip 7 and BMZ with any reductions recommended by the makers.