Charge problem

[Aguila Blanca]

For those who may not know (and I didn't, until a couple of months ago), the pre-1873 Colt Richards-Mason cartridge revolvers weren't chambered in .45 Colt, they were chambered in .44 Colt. Basically, that meant a case about the size of a modern .44 Special, topped with a heeled bullet having a bullet diameter of .451" or .452" and a heel diameter of .430" to fit into the .44 caliber brass.

https://en.wikipedia.org/wiki/.44_Colt

https://www.chuckhawks.com/44_Colt_original.htm

It's a long story, but I have a modern conversion clone with a .44 black powder barrel, which means it takes .45x diameter bullets, but the cylinder is bored for .44 caliber cases. Starline makes the correct brass, and I found a source for the proper, heeled bullets.

My first attempt at loading .44 Colt Original has been a moderate success: they shoot, they're moderately accurate at typical handgun range, and I didn't blow up the gun. But the cases come out absolutely black -- they're clearly not obturating. Today I ran five rounds through a chronograph to see where I stand.

Average velocity: 546 fps
Highest velocity: 635 fps
Lowest velocity: 493 fps
Extreme spread: 142
Standard deviation 59​

I'm disappointed in the consistency (or lack thereof), but I'm still working the kinks out of what is for me an experimental cartridge. To crimp a heel bullet I had to have a special roll crimp die made just for this cartridge. Seating and crimping are a bit problematic.

But ... the bottom line is that the velocity is too low. My load is 4.9 grains of Winchester 231. The heeled bullets are 220-grain, lead round-nose. The 220-grain bullet falls right in between load data for .44 Colt on the Hodgdon web site -- they have loads for 200-grain and 240-grain bullets.

I'd like to bump the velocity a bit, but I load on a turret press with a Lee Autodisk powder measure. That means I can't bump the charge in increments of 1/10th of a grain. At a guess, the next larger aperture will probably dispense about 5.3 grains. 5.3 grains of Winchester 231 is what I load for .45 ACP, behind both 230-grain and 185-grain bullets.

Is that too much of a jump for the .44 Colt?

 

[egd]

I can't answer your question, but this is just an FYI, if you're interested.
I started on the Lee classic turret with the Autodisc. I quickly said the autodisc is not for me because you don't have fine adjustment of powder. I bought a product called "the perfect adapter" which goes in the powder die, then you can mount a reguler powder measure into that. (I used an RCBS uniflow). When the powder station rotates to the shell just flip the handle and your powder drops into the shell. Easy-peasy.

 

[ADIDAS69]

Dither

Go down to your local consignment/goodwill and poach the vibrator from a baby swing. Tape that to your press frame. I did this and all of a sudden my loads from the auto disk system were perfect. Also hope down to your local fastener store such a place like Tacoma Screw or Grainger and they’ll have drill bits in every micro increment needed to get you the perfect size hole. Just be sure to mark the altered disk VERY clearly.

 

[PA-Joe]

Are you double tapping on the measure's handle so that you get a full drop of powder?

You need a quick double tap to make certain enough powder drops into the measuring hole. Then you need a double tap to make certain all of the powder falls out of the measure.

You have to be consistent in how you do your drops.

 

[Unclenick]

AB,

Can you fill in more information?

QuickLOAD has data for pre- and post-1940 44 Colt, neither of which is your cartridge, based on bullet diameters (0.447" and 0.443" groove diameters, respectively), and I suspect the Hodgdon loads are for the latter. I can tell you that it reports 4.9 grain of HP38 (aka, 231) producing 11,044 psi) with a 250 grain Lyman bullet that I dialed down to 240 grains and shortened 0.023" and used at their 1.38" COL, and that is within about 10% of the numbers reported by Hodgdon for a different bullet that may or may not have the same length, which is about as close as QuickLOAD gets with some straight wall cartridges, but, still, it isn't exactly your cartridge. Also, as there is no current SAAMI standard for any version of the 44 Colt, I have no clue what Hodgdon's test barrel chamber looked like. The only current standard is from the CIP, which is for the 0.443" bullet diameter and which allows for a maximum average peak pressure value of 1000 bar or 14,504 psi, but with no current standard for the copper crusher that Hodgdon used.

Two possibilities for your symptom occur to me. One is that the case you are using is for the smaller diameter bullet and a correspondingly smaller diameter chamber in the later versions. I don't expect this to be true based on the CIP dimensions, but leave no stone unturned. Let's see how much the OD of the case has to expand to obturate the chamber to gas flow and make sure that is within reason. Measure the chamber ID and the case OD and see what the difference is. The chambers will probably need to be slugged to get an accurate set of numbers.

A second possibility is your wider bullet at your particular COL is not seating as deeply as the Hodgdon example, and that will reduce pressure by leaving more powder space in the case. The dimensions below will tell us.

So, the information that interests me is your bullet heel length and your actual case length and the case water overflow capacity in grains of water weight up to the level of the case mouth for a new or resized case, whichever you are using (seat a fired primer to plug the flash hole). Let us see how the pressure prediction compares to the previous one with that data. If it drops some percentage we'll have a good guess at how much lower your actual pressure is than Hodgdon's (assuming that it is lower). The soot makes it sound like it is.

In the meanwhile, if you have some Hodgdon Clays, try Hodgdon's load with that powder. It is rather quicker than 231 and may make pressure fast enough to expand the case for a better seal before the bullet really gets moving and lets gas start escaping.