Roundballs and pressures

[Cannonfuse]

Hello! I’m curious about how much pressure pure lead roundballs loaded with black powder (and substitutes) generate. I was searching for information on this subject but I didn’t find anything of value. Is there any data, like this chart of modern calibers http://www.leverguns.com/articles/saami_pressures.htm available regarding roundballs and black powder?

For example, what’s the maximum generated pressure of a .44 cal roundball loaded with 25-30 grains of black powder? What about smoothbore pistols vs rifled revolvers?

[T. O'Heir]

The Lyman BP Handbook and Reloading Guide has that info. About $30 from Amazon or directly from Lyman. I'm not seeing any such data on-line though.
SAAMI deals only with metallic cartridges that are loaded by Manufacturers who are loading to SAAMI specs. SAAMI being a voluntary thing. I don't think they ever deal with BP stuff.
A smooth bore pistol is a short shotgun. Flinter pistols, like 'Kentucky' pistols, are rifled.

[Catman42]

what are you shooting this load in? their has been a lot of talk on some muzzleloader sites about 4f verses 2f in real black and the pressures. i dont remember the sites but raised a real rucus. lots of anger. however the truth was proven by some that 4f didnt have any higher pressures than 2f. just cleaner to shoot. a shooter form england used 4f in all his black powder guns and he had a lot of them. i tried it once in a 50 cal muzzleloader and worked good for me. as to the pressures, cant address that but if you go through all the muzzleloader sites you will find data. good question for those who like research.

[rodwhaincamo]

The 2nd edition excludes the pressure data. You need the 1st edition, which is out of print. This for revolvers. It does have muzzleloader pistols data. This is the page showing Goex (standard - not Olde Eynsford) 4F velocity and pressure:

[rodwhaincamo]

No pressure data, but 35 grns of Goex 3F and a .451” ball produced 848 FPS. It takes maybe 24 grns of 4F to achieve that velocity according to Lyman.

[rodwhaincamo]

4F is what Europeans use in handguns. Even the prior bottles of Swiss powder showed this:



A fellow doing research on Civil War paper cartridges tested the ones made by Hazard Powder Co and found the .44 caliber cartridges to contain 4F and found it equivalent using the original pendulum practice for determining velocity/energy as Swiss 4F. Records show the Hazard’s Pistol Powder cartridges using 36 grns to push a 211 grn bullet:



A museum curator who took apart a lot of late 1800’s metallic cartridges found 4F and finer powders to be common even in large calibers.

[Catman42]

thanks for the info from lyman as to the ratio of 4f to 2f to achieve the same thing. never saw that data before, its good info.

[rodwhaincamo]

Though 4F May have been somewhat common in revolvers I see no real reason to use it when we have a few excellent 3F options to obtain the kind of velocity one may want. For me these .44/.45 cal revolvers are backups while hunting and if I can achieve tight groups out to 25 yds with a rest it may also become a primary.

Everyone seemed to say these .44’s were too anemic, that they’d only achieve .38 Spl levels of performance with a bullet and that just wouldn’t be enough to be humane. This is true if you use you the plethora of weaker powders. But with Swiss, Olde Eynsford by Goex, and Triple 7 these can get to standard .45 ACP levels (350-400 ft/lbs). That, to me, is plenty. And I can still use a healthy charge in my rifles and possibly shotguns (often I see 2F or larger actually does better). If these powders weren’t available I’d likely be trying 4F standard Goex in my revolvers at the least.

[Hawg]

I use a lot of 2F in revolvers. I can't tell any difference in power with it. Maybe if you ran it over a chrono there would be a difference but to me that wouldn't be enough difference to matter. I have seen charts that show Pyrodex to be the equivalent of Swiss. I don't doubt it as I use both.

[rodwhaincamo]

I’ve actually been a little interested in trying an energetic 2F. I haven’t tested much but 3F hasn’t been very accurate in my .50 cal rifle. If I can get acceptable performance in a revolver I’d switch (assuming accuracy is still good). 2F Swiss, Olde E, or T7 should be much more energetic than 3F standard Goex and other powders.

I’ve seen impressive numbers from Pyrodex just as I’ve seen what I feel are dismal numbers. Even Hodgdon shows less than Swiss/T7 performance on their site. Because of this, and that I don’t like the fouling I get in my revolvers, I won’t use it.

[44 Dave]

After "unloading" revolver chambers and bp cartridges the powder is squashed to something that is a lot finer grain. powder loaded with a hand ram rod can't get that kind of crushed.

[rodwhaincamo]

That doesn’t account for the paper cartridge that was disassembled.

The curator from the museum is a BP enthusiast on a few of these forums. I’m going with his observations as he’s familiar with BP and with old weapons and ammunition. It seems metallic cartridges don’t overly compress the powder as they might with a percussion revolver. Granted I don’t reload BP and am not all that familiar with them, but what I’ve read was very light compression.

[Hawg]

The only way you're going to crush black powder into a finer grain is with a compression die and I'm not sure that would do it.

[Catman42]

some say use a compression die, i never ever do. just a good 60 thousands wad ontop of the powder. my 38 special and 45 long colt cowboy revolvers shoot very well this way.