Agreed brother! And you are absolutely correct about the Enfield too. I only mention the Mark IV 303 British because it was the British evolution of the Enfield which was one of the first purpose built purely for smokeless powder. Unlike some of the original Mauser action rifles that actually were loaded with black powder ammo. And the difference in cup between them and even modern lever guns reflects it. That was my only point. Well, that and I just flat LOVE my MK IV! ;~)Archer wrote:jdb,
The 1917 Enfield isn't part of the Lee Enfield family...
...My comments were as noted not pointed particularly at this specific situation where things may fine. Rather at the implication that, because things are generally designed with a safety margin and that the lawyers tend to increase that margin, that pushing on such a margin is generally safe. Any safety in pushing the limits is very much a matter of the specific circumstances.
But the thing is, a modern Marlin 45/70 as per Marlin has a recommended MAX cup of 44,000. Some of the factory 303 British loads are 48,000 cup. So who knows what kinds of pressures those things could take as a maximum? I know for SURE that I wouldn't want to be around when the thing failed! ;~)
The SMAAI date reflects that too. The MAP they list for modern 45/70s is just over half that of the 303 British. Heck, the 45/70s are actually 8,000 psi less than the MAP they list for 44 magnum. Most manufactures load to the lowest common denominator for the caliber.
And we do the same thing...or SHOULD!
As an example, I load some 300 grain wrist twisters for a 44 magnum Super Redhawk that I wouldn't shoot in a Model 29 Smith if someone would pay me a million bucks. I KNOW it would destroy the Smith...and likely my hand. But I also know that the big ol' Ruger can take it. By the same token, I might load up some 45/70 BEAST for a Sharps style rifle...modern replica of course...that I wouldn't even THINK about loading into a Rossi or Marlin lever gun.
As you say, there are just too many possibilities for failure with the design to push boundaries without understanding the designs and variables.
Heck, there are all manner of variables in guns beyond even loads that effect pressures. Even the twist used by individual manufactures effect how much pressure the same round will produce in that gun. Is it a land and groove or groove bore? Is it a free bored or long throated rifle, meaning how quick does the rifling grab the bullet? All effects pressures and all things that we should consider when deciding how far to push something.
As to claims of huge pressures with black powder, I'm with you. I'm gonna take that with a grain of salt. I've never seen any data that supports anything like that and the physics don't support it. As a matter of fact, everything I've read or experienced is the opposite of that. Black powder burns in a VERY different way than modern smokeless powder. If it didn't, there'd be a heck of a lot of dead or left handed ol' boys round here from all the double and triple charges we've shot out of our front stuffers over the years. LOL
It's just not capable of producing the kinds of pressure smokeless does in a unobstructed barrel where there is a place for the pressure to come out. It just flat does not produce the same kind of energy. But even with smokeless powders, there is a HUGE difference in the pressures that different powders can and do produce. Like 4.3 grains of Unique and a 158 grain round will go 920 fps and make about 16,000 psi. while 4.2 gains of Winchester 231 and a 158 grain bullet will go right at 800 fps and make 15,000 psi. 1/10th of grain difference and 1,000 psi increase.
By the way guys, I dug out a couple of my old loading manuals. My Speer book list 22 grains of fffg black powder for a 36 cal cap and ball. Which is the grand-pappy of the modern 38/357, but it list 21 grains of Pyrodex. Now I'm not sure if that is because of the large size of the grains of Pyrodex, which don't compress like black powder, but whatever the reason, they did recommend 1 grain less for the same caliber.
AND, I dug out my pistol flask with a 28 gain measure on it. A 357 magnum brass filled SLAP to the top is 28 grain. By volume of course. So just guessing, by the time you allow room for a bullet so that the round is short enough it will cycle through our Rossi 92s, I guessing the BEST we would be able to stuff into a 357 is about 24-26 gains of black or Pyrodex and maybe 20-22 grains in a 38 special brass. So there is a good place to start for anyone thinking about it. And that's only going to be a few grains more than what Speer recommends for a cap and ball.
But even at that, you'd need to compress the powder quit a bit to get a bullet in them. Not sure how that will work with Pyrodex. Not sure how much packing it will do? Never tried it. I've got 3 or 4 pounds of it, but as I said, I don't use the stuff in my muzzle loader. Too messy and it's inaccurate in my beloved ol' TC Renegade. ;~)
As far as gap goes, have any of you guys ever seen a lodge fire. I have...several times. I've had it happen twice with my Remington New Model Army. Bad powder and thump, I'm cutting a stick to pound out the round! LOL
But as someone else said, the thing I'd be most worried about with using so little black powder that ya have a gap is lodge fire, not an explosion. ;~0
Best advice, know your gun, know your objective, know the data and HAVE FUN!
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