??? FPS??

[megasupermagnum]

Yeah, a lot. All that was done nearly a century ago. Center fire shotgun is faster.(period)
It's a common global history. Those facts are easily found on line,,
I mean, what is your goal here?
Honest truth is, your ML smoothy,, will never compare to modern magnum shot shell in fps.
It's easy,, the lead time learning curve is different.
Modern CF shot shell isn't superior in harvest to ML,,

Really? What kind of ammo could you possibly be referring to? In the constraints of a shotshell, maybe. Comparing a shotshell to a muzzleloaders, no way. They are fairly comparable with most loads, but the pressure of a muzzleloader is only 1/2 or less. Loaded to equal pressure, I'd bet blackpowder is faster.

 

[necchi]

In the constraints of a shotshell, maybe.

Uhm, yeah(?) I thought that was the topics question.

Comparing a shotshell to a muzzleloaders, no way. They are fairly comparable with most loads, but the pressure of a muzzleloader is only 1/2 or less.

Yes.

Loaded to equal pressure, I'd bet blackpowder is faster.

Yeah, but that's not possible is it?

Oh I could dig I guess, and find the fun facts, I was just speaking to the OP with experience using both all the way back to the 60's with over the counter paper hull center fire 2 3/4" 12 gauge, as a hand loader for said, compared to the same today available over the counter shot shell,,
Sorry,, I'm wrong. Your right.
BP Ml smooth bores win-out every time,, (if only the pressures could be the same)
(with leather cups,,behind a bee's nest wad, with a "spit patch", then a wad of grass for "over-shot")

 

[megasupermagnum]

I see nowhere anyone asked about blackpowder in shotshells. Yes, it is possible to load a blackpowder muzzleloader up to the 11,500 psi SAMMI voluntary limit for a modern 12 gauge shotshell.

 

[Lorne Johnson]

I haven't seen him post in over a decade, but the used to be a chemical engineer on the forum who explained this rather well. When ignited in the chamber the flame front in black powder is subsonic (burns about the same way it does in the open, which is pretty fast, but subsonic). Modern powders (which have a relatively slow flame front in the open) have a supersonic flame front in the chamber, he noted that the powder was mostly burning before the shot leaves the shotshell. This radicachanges the pressure curve, among other things, and frankly makes it hard to compare the two systems.

With black powder the start of the burn moves the shot and thus increases the volume in the burning chamber (which lowers the pressure being achieved, and the more powder one adds, the more this effect takes place). Most guns seem to hit a sweet spot (or balance) for shot in the vicinity of 2.75 to 3.25 drams. This seems to take game just fine out to 30 or so yards, so I just take what BP gives and resist the temptation to attempt greater range.

Interestingly, back when I shot modern guns, I looked at pellet speeds at 30 yards I was surprised at how little advantage one got with the really fast loads (although fast loads do reduce lead noticeably). Probably important for increasing the energy of steel shot, but not much for lead.

 

[megasupermagnum]

I haven't seen him post in over a decade, but the used to be a chemical engineer on the forum who explained this rather well. When ignited in the chamber the flame front in black powder is subsonic (burns about the same way it does in the open, which is pretty fast, but subsonic). Modern powders (which have a relatively slow flame front in the open) have a supersonic flame front in the chamber, he noted that the powder was mostly burning before the shot leaves the shotshell. This radicachanges the pressure curve, among other things, and frankly makes it hard to compare the two systems.

With black powder the start of the burn moves the shot and thus increases the volume in the burning chamber (which lowers the pressure being achieved, and the more powder one adds, the more this effect takes place). Most guns seem to hit a sweet spot (or balance) for shot in the vicinity of 2.75 to 3.25 drams. This seems to take game just fine out to 30 or so yards, so I just take what BP gives and resist the temptation to attempt greater range.

Interestingly, back when I shot modern guns, I looked at pellet speeds at 30 yards I was surprised at how little advantage one got with the really fast loads (although fast loads do reduce lead noticeably). Probably important for increasing the energy of steel shot, but not much for lead.

Either you mistook what he said, or he wasn't a chemical engineer. All propellants react differently under pressure than at atmosphere. That's high school stuff. Secondly, if it were even remotely true, then you couldn't get supersonic with blackpowder, which is false in every sense of the word. Rifles with patched balls are often up in the 1800-2000 fps range. Some as high as 2200-2300 fps, and you could probably get more if you really wanted to, although nobody ever gets accuracy past that. Shotguns hover around the speed of sound because that's where shot patterns best.

The second part of that statement about the pressure curve is not true either. The pressure curve of blackpowder is nearly identical to modern smokeless shotgun powders like Unique or Bluedot. It doesn't matter if we are talking about a 45 caliber rifle, or 10 gauge shotgun, blackpowder pressure curves are rapid. The biggest difference between blackpowder and modern smokeless is how much energy is packed volume for volume. You can absolutely generate high pressures with blackpowder. Standard 45-70 loads with a 405 gr bullet and blackpowder are in the ballpark of 20,000 psi. That's low by modern cartridge standards, but red zone in most muzzleloaders. I'm not one to load to failure, I like my guns. This year I plan to do some pressure testing with some serious loads of blackpowder to show what kinds of pressures are possible in a shotgun.