Pressure Spike in Smokeless Powders

[KirkD]

That Ballistol trick is good to know. I tend to be a perfectionist when I clean BP out of my arms, especially sixguns, so it turns out to be about a one hour process per gun. Part of the problem is not knowing how much cleaning is enough, since no one else around here shoots BP in their old guns. You are right about the old corrosive primers. In my opinion, they did more damage than BP ever did, judging from how the first inch of the bore in front of the throat looks in a lot of old guns.

[JohndeFresno]

Bravo! Too much to absorb at one sitting - archiving all pages of this blog. Good work, gentlemen - very impressive research, observations, and dialog.

[Mike D.]

Unless I am loading HV .44-40 cartridges I steer clear of 2400. It's perfect for smaller cases line the .25-20 and .32-20, but Unique, and in some cases Bullseye, works best for the larger cases, like the .38 and .44-40. Like Sixgun said 6.5 grains Unique is perfect for the older SAs, S&Ws, '73 Winchesters, Colt Lightnings, and other guns of that era. I go up to 8 grains for my "smokeless" Frontier Six Shooters. Many thousands of happy rounds run through those guns and they haven't changed one iota.

[w30wcf]

Personally, being somewhat of a traditionalist, the original 44-40 smokeless rounds contained 14 -17 grs. of powder, depending on the propellant used. THerefore, the vast majority of my 44-40 cartridges are loaded with powders within that range. I find that 2400 and 4227 to be excellent in that role.

w30wcf

[AJMD429]

Bravo! Too much to absorb at one sitting - archiving all pages of this blog. Good work, gentlemen - very impressive research, observations, and dialog.

Yep - VERY educational...!

One OTHER issue comes to mind as far as 'old steel' vs. 'new steel' - not just the bursting strength, and stretch, but how about compression as in pressure-peening the chamber or even bore sidewalls? Is that just basically incorporated into 'stretch' engineering? I just wonder if rapid-spiking pressure would tend to compress the steel, short of actually bursting it, or if that would show up as 'stretch' when people measured their guns after extensive rapid-spike powder use.

Personally, I plan to stick with the slow-spike smokeless loads for the reasons KirkD mentions, but this has been a very interesting thread.

[bigiron]

Has anyone actually taken examples of antique steels, perhaps otherwise unsalvagable frames, cylinders,etc, and subjected them to destructive metallurgical testing? It would be satisfying to see real numbers attached to this discussion. I've not turned up much in the past beside some second hand references to testing of decarbonized steels used in late 19th century shotgun barrels, the elastic limit given was in the 25000 psi range although i have no information on the manufacturer. Kuhnhausen has rockwell tested a number of SAA frames, but the jury is out on whether hardness can be directly related to tensile strength. Subjectively, I own two first gen saa Colts, an 1899 non VP and a 1905 VP. Even hand tighting a screw you can "feel" the difference in the steel as the screw torques up; less "strech" in the 1905. I shoot
Trailboss, by the way, in both of them as they have 2nd gen cylinders. I find it easy and as accurate as i need to be for moderate plinking duty, but this thread has got me interested in working up loads with some the the mentioned powders.
Nice to see a thoughtful and informed discussion on this topic instead of the knee-jerk hysteria that is usually provoked by the idea of using smokless in "BLACK POWDER" guns.

[Mike D.]

Seeing Driftwood's post about VP marks on Colt SAs made me take a look at mine. None of my 1st Generation, 1903-08 guns have that mark. These old shooters have had countless rounds fired through them with absolutely no issues.

[Bryan Austin]

Another forum with the same guys

Again, great topic, pards and information!

[Bryan Austin]

Personally, being somewhat of a traditionalist, the original 44-40 smokeless rounds contained 14 -17 grs. of powder, depending on the propellant used. THerefore, the vast majority of my 44-40 cartridges are loaded with powders within that range. I find that 2400 and 4227 to be excellent in that role.

w30wcf

Which do you prefer for revolver and rifle?

2400 or 4227 (IMR?)

What about for the 45LC?

[JohndeFresno]

Another forum with the same guys

Again, great topic, pards and information!

Welcome, Savvy Jack!

[Griff]

Welcome Savvy-Jack. Fun post to review. Forgotten what I'd posted on it. Shot off an PM to a pard and then read on down and I had said the same thing in another reply... Must be slippin' another cog!!!

[Old Time Hunter]

Hobie, hope you put this thread back in the stickies...too good to let it fall through the cracks.

[marlinman93]

Some very good information here, and I like that nobody is getting their panties in a twist either!
I would just add that in over 30 years of owning and reloading old single shot and repeating rifles, I've used BP once, and wasn't all that excited about it. In these many decades I've used smokeless powders almost exclusively, and never hurt any of my old guns, or myself.
I think with proper care, either powder will be equally safe, so it's just a preference of what you personally enjoy shooting, and cleaning up after. I like smokeless.

[Pop Watts]

Hey Marlinman93.
You sure dug up an old post.
Pop

[Les Staley]

Dang, Pop....glad yer still with us..four years with some of us in the shape we're in makes you wonder. Anybody else from this old post still alive? Great info, by the way...Les

[otteray]

Interesting about Blue Dot and low pressure. I've got a full 4 lbs sitting unused since Hogdon gave it the heave-ho in the 41 mag. Is there any published data with it for 38 WCF?
I still haven't found anything to beat 6.5 gr Unique, though, for accuracy in the old Marlin 1889.

[Bullard4075]

Bravo! Too much to absorb at one sitting - archiving all pages of this blog. Good work, gentlemen - very impressive research, observations, and dialog.

+1!
I too request this be a sticky.

[Old Time Hunter]

What a great read...glad it was brought back up.

[JohndeFresno]

Hey Marlinman93.
You sure dug up an old post.
Pop

Dang, Pop....glad yer still with us..four years with some of us in the shape we're in makes you wonder. Anybody else from this old post still alive? Great info, by the way...Les

I second that motion - haven't seen your posts for a long time - good to hear from you!

[earlmck]

What a great read...glad it was brought back up.

Yep -- I'll second that motion.

And though I haven't used it much in these black-powder pressure level loads, Blue Dot has been much nicer in the higher velocity (where you want a gas check bullet) loads than the 2400 generally recommended. But I surely can't find any published data in 38/40 and that data w30wcf found from the old Hercules book on the 44/40 is more than I could find amongst my collection on that cartridge.

And otteray, my Lyman manual #47 thinks Blue Dot is the best thing going in 41 mag. If I had a 41 mag and a batch of Blue Dot I would certainly be putting those little blue dots to use, even if Allient fails to recognize what a fine pistol powder it is.

[otteray]

I just emailed the powder company about the blue dot and was told that because of a different method of pressure testing combined with recent primer mixture changes, 41Mag is still considered a bad idea with Blue Dot.

[Nate Kiowa Jones]

KirkD"
Sent ya a PM

[mark]

Bravo! Too much to absorb at one sitting - archiving all pages of this blog. Good work, gentlemen - very impressive research, observations, and dialog.

I certainly agree with your comments. It's a topic to be "tucked away", and probably printed.

Thanks Mark

[Malamute]

Kirk, do you have the images of the pressure curve comparisons on your computer that you could post as attachments rather then the photobucket links which arent usable now? I tried getting into the album, but its restricted, and the pictures dont link back directly to see the originals hosted there. Many hotobucket images can still be seen on their site, but not 3rd party hosted. Unfortunately, the linked album is set to restricted access.

[Bryan Austin]

When testing/comparing pressures curves, one must compare apples to apples. Regardless of cartridge used, one must test a cartridge using the same velocities with both powders, then compare pressures. Lowering a given velocity will lower the pressures, and pressure curves, for acceptable use for some cartridges.

For example:
44-40...of course right?

Back Story...
Original Black Powder velocity of 1,325fps produced maybe 17,000cup, later cartridges reduced to 1,300fps @ 13,000cup with the use of post 1884 headstamped cases and maybe a different black powder formula. These black powder loads would have produced a fairly sharp pressure curve for black powder...more shallow with the later version. Thus comparing a 17,000cup black powder pressure curve with a 13,000cup smokeless powder pressure curve, that both maintain 1,300fps velocities.

Original smokeless powder replacements, using DuPont No. 2 smokeless RIFLE powder created at least 1,000 cup less pressure and nearly the same pressure curve as black powder. The difference most do not understand is that later use of fast burning pistol powders created higher pressures and sharper pressure curves in order to produce the same velocities! With the 44-40, Winchester boasted on maintaining original velocities when they offered smokeless powder, specifically for the Winchester 73'. Folks back then wanted hunting loads, not stupid competition mouse fanny burp loads.

Most smokeless pistol loads now days barely produce between 6k (cowboy fanny burbs) and 8k (hunting loads) pressures and barely hit 44 Henry ballistics...and perform at minimums for revolvers of any year. Dumb people are quick to sue for their own ignorance & lies and the Liberal judges cave to them.

Buffalo Bore is the ONLY modern factory loaded ammo at a reported true max pressure load. Their loads produces 1,300fps in rifles at factory rep reported max [13,000cup] pressures using hard cast .429 bullets. If used in smaller bores, the pressures can increase beyond max pressures.....thus you know the rest of the story with Liberal judges!


Here are some pressure charts: https://sites.google.com/view/44winches ... andloading

and here are some 44-40 pressure charts: https://sites.google.com/view/44winches ... andloading

What I did not do during my tests was to test pressures by velocity, rather all my tests were based on max published loads or used handloads. I wish I could test more loads but I no longer have my equipment....and the computers are almost more than I can handle.