black powder question

jethunter

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Has anyone ever seen black powder burn rates on a burning rate chart, similar to what we see for smokeless powders? I'd be really interested to see where ffg and fffg rate on the smokeless burn rate chart.
 
Big problem there, Jethunter, is that Black will burn at differing rates depending on how much it is confined.

Out in the open it's scary enough when you are burning off a train of old stuff: it's GONE before you can even get out of the way. Bullseye, for example, is extremely slow in comparison.

Inside a cartridge, I don't even wanta guess.

I have no idea how they do it in the movies. There, they always show a sputtering trail of Black leading to the powder-barrels in the pirate ship or something. In real life, it would be "FFFFfft!BOOM!!!" and the Hero would be looking for a parachute among all those pirate-ship parts surrounding him.

Hope this helps.
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I guess they'd do it the same way they do smokeless powders. Big problem would be that BP isn't as uniform as the smokelss propellants, depending who made it, what recipe they used and so on.
 
Yeah, for sure there is no comparison to be made with smokeless of any sort. IF they did list a burning rate some idiot would be sure to take it as an endorsement to use smokeless in his muzzle loader because the burn rate seemed "similar" to a smokeless powder.
 
So how similar is Unique to Black then burn rate and pressure wise, I mean obviously you can use it in antique back powder firearms.

So there is smokeless that is relatively the same.
 
Absolutely not! Back up do not pass go! Unique is no safer then any other smokeless in BP firearms or cartridges. Within the same maker all BP is the same just the grains are larger or smaller, and the lines cross alot. This idea of any kind of equivalency between smokeless and black is not possible and very dangerous.
 
So why are so many Black powder gun users have great safe results with mild loads of unique then.

And all the smokeless loaded .32 rimfires are safe to use in the BP guns, I and others have shot plenty of it.

The right smokeless in the right amounts must be safe otherwise id be without fingers or my guns.

I was under the impression that smokeless 2400 or slower was O.K. when used carefully.
 
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Some folks use small amounts of alot of different smokeless powders in guns designed for Black powder, there is however no correlation between Black powder and smokeless other then published pressure levels of both. I am not a believer in the safety of using those figures as the pressure curve is different, and the stresses on fatigued metal parts occur in different places, for differing duration. Black powder is safer in these old guns as cases full of powder are usually safe loads and if there is too much powder it will usually just blow out the end of the barrel unburnt.
 
At one time there was an entire class of smokeless and semi-smokeless powders which were safe in Black Powder guns. These were the old BULK powders. They could be loaded BULK FOR BULK with Black and would give similar performance internally as well as externally.

There was, however, a serious difference: the Bulk Powder charge WEIGHED a lot less than the Black charge.

The Bulk powders have all gone the way of the Dodo Bird, but there is ONE old-time powder left which is ALMOST in the same class, but not quite. This is SR-4759. The SR is for "Sporting Rifle"; it is emphatically NOT an IMR (Improved Military Rifle) powder.

Using SR-4759 in RIFLES, you can pretty much duplicate the Black Powder performance by using the SR-4759 at 38 percent of the Black charge BY WEIGHT. It is a very bulky powder but you can NOT load it bulk-for-bulk as the old-time powders were loaded. At 38 percent-of-Black levels, this works out to 29 grains for my .43 Mauser, about 27 grains for a .45-70, 38 grains for a .50-100 and 42 grains for a .50-110 Express. In each case, you have a charge which will duplicate the Black powder performance AND pressures; you will also have pretty near a full case.

SR-4759 works fine in RIFLES (but I still run my Sniders on Black) but it is NOT for shotguns, nor is it for pistols. It would NOT be safe in either gun.

For pistol cartridges, you CAN use LIGHT charges of the faster single-based and double-based powders, but in NO case are these charges anything at all of the order of the original Black charge. A friend is using 6 grains of Unique for his .44-40.... and he is getting much the same performance as if he were using the full FORTY grains of Black.

There is a HUGE difference between modern smokeless powders and the original Black powders. The ONLY near-exception is the very last of the old-time powders: SR-4759.... and you have to know how to use it and you have to be CAREFUL with the stuff.

There is NO smokeless powder which you can load bulk-for-bulk with Black, using your little dippers or powder-horn measures. The very last of these powders went to the knacker's yard many years ago. What we are left with is their COUSIN, so to speak, an ALMOST-but-not-quite-Bulk powder: SR-4759 (long may it continue in production!).

HOPE this is clear enough.

DON'T want anyone getting hurt.

PLEASE read carefully.
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trust me, I am not on side of using smokeless in black powder firearms when I ask this. Just wondering where the new trail boss powder would fit in as compared to the old time powders discussed in this thread.
 
I am new to black powder shooting but have done a fair bit of research and decided to go with a black powder substitute to start with. I have a pound of Jim Shockey's Yukon Gold that I will use with my BP revolvers in .36 and .44 cal. the main reason being to avoid the corrosive effects of real BP. If this stuff works out I will continue to use it, it may be under powered but I am sure it is safe when used on a volume for volume replacement for BP. I have some real BP on order so that I can try it as well, it might not be as bad for corrosion as I have heard. When I get my guns back together I will load alternate cylinders with BP and substitute and do a direct comparison. There is a sticky about using smokeless in antiques that might help.....:)
 
I too am fairly new to BP but I have tried pyrodex p and I am currently using Triple 7. I like Triple 7 because its less corrosive than BP and pyrodex and it does not contain sulfur so no bad egg smell. Also easier to clean up even with just plain water...I also think that it is hard to compare BP and its substitutes with smokeless powder because they are so different in the sense of how they are measured and how they react when ignited. Its like comparing a flint lock rifle with a Remington 700 rifle both shoot a projectile but at the same time they are not the same. Old and new technology is what it really comes down too. So BP and smokeless are the same but totally different at the same time and not compatible with each other, its as simple as that.
 
I have lately read several online opinions that say the pressure curve on FFFG black powder is similar to Unique, and BP FFGg to Aliant 2400. That was why i started this thread - i'd like to see a reliable source confirm these opinions. .

IMO and experience Unique is no more harsh than black powder on the old pistols when loaded properly. Notice the underline.

BUT - there's a lot more that can go wrong when you use smokeless in a cartridge originally designed for BP. As Ben pointed out - you can accidentally overcharge with black powder and you probably won't hurt anything and might not even notice. But a couple grains too much unique in your antique revolver cartridge and things can break. Accidentally double charge with Unique and maybe you have a 40,000 psi grenade to shoot in a gun that's built for 12,000 psi.

People (and factories) have been successfully loading smokeless in blackpowder cartridges for well over a 100 years now, so it's not unsafe in itself but it requires more vigilence and the margin of error is very much smaller.
 
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Shortly after I got my first Mouser (71 Mauser carbine), many years ago, I pulled down a fresh round of DOMINION .43 MAUSER ammunition. This stuff was for the '71 and for the '71/'84 and also was supposed to work for .43 Spanish.

I knew it was smokeless ammo, but I was more than a bit surprised to find quite a small charge of little hairy PINK balls. I don't think there was anything even close to 29 grains there but the ammo shot nicely and REALLY left an impression..... on your shoulder.

I never did tell the little rifle that it was shooting PINK powder; it would have gone on strike! Nice thing is that the shells reloaded nicely with SR-4759, available then as now.
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Have you ever opened old ammo casings and looked how much powder is inside? Not much sometimes. That's why I'd rather use google and try to find out how much BP was really used or what other people were using with success and then start a safe load with Unique. The only reason BP is considered "safe" is that's in the old days they just filled up the casings to the limit or I read "it is not safe to use smokeless powder because of the failure rate in measuring". Oh well, if that's the reason, ...
 
the one big issue that I have with using smokeless in a BP cartridge is the amount of empty space left from using greatly reduced loads,and the resultant pressure.
I know folks use cream of wheat etc to "top up" rifle cartridges but to what point does this remain practical?
What amount of case volume can you utilize with a filler and still be safe/effective?
Would say 20% case volume under 80% filler still be a functional load?
Hypothesizing of course.
 
Black powder corrosive? Then why do Martini's and Sniders most often have excellent bores? Now some BP substitutes ARE corrosive! I should think that all the corrosion problems result from rifles using corrosive primers that are not cleaned the same day they are fired. BP residue attracts moisture if you don't clean it out. Look at all the antique .22's fired with BP with bores like five miles of gravel road.
 
With SR-4759 you don't use a filler. The powder itself ignites quickly enough and is fast-enough burning that you don't need one. This is one of the characteristics of the old Bulk powders that it has retained.

It is also very bulky for its weight and so there isn't as much room left in the casing as you might surmise. Double-loading is very near impossible!

The 38-percent-by-weight standard for shooting SR-4759 in Black powder rifles was pointed out in many of the OLD handloading manuals. It is not original with me; I have just been using it for the last 45 years.

There are SR-4759 loads in the latest Sierra manual, too. It is the ideal powder for reduced loads. Two years ago, my range buddy of many years bought a .300 Weatherby Mag on a pre-'64 Model 70. He knew that his heart could no longer take the pounding from full-house loads, so he bought 100 brass.... and we spent his final year at the range, shooting a .300 Weatherby that was making tiny little groups, zip recoil, and producing MOST of the power of a .30-30! Fun!
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