Let me see.... In spite of my wealth of ignorance on the subject I'm going to take a shot at your points one by one. I used to be a gun writer, so my lack of information in some areas shouldnt be a barrier:
own two of them. I have some set-up problems I hope you can help me solve.
1. Both pistols are so tightly assembled the barrels' assemblies appear to be forge-welded in place. How can I disassemble?
* I've had two of them and rifled barrel assembly unscrewed readily on both. The little lever at the bottom of the frame locks s the assembly to the frame and, on a brand new one takes some pressure to move downward. Be sure to put the hammer at half cock, then just grab the barrel and do the counter-clockwise thing. On my first one, I wasn't even aware that the shot barrel would unscrew and found it out by mistake after shooting this new one a bit.
The good news is that, while the screws on these and other replicas range from extra loose to air-hammer tight, they are not welded or staked in-however much it may seem that they are.
The side plate (donut shaped) bushing screw on the left frame is split with the nose of the hammer screw sticking through. I had to file down the screwdriver blade in the picture to fit and then hope that it would not break under the massive torque required to loosen the screw. I didn't heat the frame up nearly as hot as some recommend for this but did pass it back and forth over an open flame a couple of times.
The hammer screw is also under tremendous torque and is one of those narrow, shallow deals that so delight custom gun makers because no 20th century screwdrivers will fit. I thinned a screwdriver blad being careful to maintian the square edges at the tip and again was lucky enough for it to work. Before undoing either of these screws, remove the mainspring as it applies some degree of pressure to the hammer.*
2. How to load center barrel so as to hold shot charge in place for long periods. I hike and ride mules. I am concerned the vertical motion will loosen this charge and render it into a grenade.
*
I worry about that too. Best bet would be to check it with a ramrod from time to time to see if it has jarred loose. I found that news paper used as wadding puts a tight grip on the charge /shot column if you pack it in tight. Recoil so so mild with the .44 chambers that it might not prove a problem. I have more work to do on this. I did find on both guns that ignition of the shot barrel is problematic because of short hammer fall. The first gun would fire but only if the web of my hand did not even touch the rear of the hammer. It seems like the touch would speed the hammer up- but it slowed it instead. My current one was taking two strikes to set off the primer until I took a file and increased the bevel on the opening of the shot barrel nipple. So far, it works fine. I also learned that I have to remove the nipple, dribble in pyrodex to prime and replace the nipple for positive ignition free of hang -fires. *
3. Have you experimented with revolver loads -- that is, RB and conical ball? Have you identified both optimum propellant-projectile charges AND maximum for LeMats? I also own several Pietta 1858 Remington "shooters'" grade target revolvers. Apparently LeMats and these (not other 1858s) revolvers use .456-.457-inch projectiles. But metal mass surrounding 1858 chambers is significantly greater than for LeMat. . . . Am I rambling??
* Its a rambling subject. and the answer is a qualified yes. On the lemat, the pietta book recommends .454 balls. I measured my chamber mouths at .448 and find that .451s seat perfectly well and shave a ring off the bullet. .454s would just overstress the ram. Best to get one of the cheap but nice chinese communist calipers and check your own gun to make sure. I am aware that the experts claim best accuracy with various whoop-de-doos such as wool or felt wads under the bullet, cream of wheat fillers between the ball and a light charge etc. I have shot these loads but do not find them interesting. The wads actually produced wider velocity spreads than ball down on powder. The old guys used a charge that fills the chamber with enough room left to seat the ball and this method leaves a bit of wiggle room for lighter charges if you like. Here's a remington load I shot with the traditionl loading method and I've gotten the same degree of accuracy with Colts in the various calibers:
The load is a 30 grain measure with the volumn equivalent of pyrodex P.
Group is one handed standing at 60 ft.
As to powders. FFFG works better than FFG even with the walkers and 50 caliber single shots. One chronograph session will have goex fffg getting higher velocities and/ or better shot to shot consistency than pyrodex but the next might find pyrodex doing a bit better in both or either departments.
Hodgdons 777 is higher energy and gets markedly higer velocities when full loads are used. It also has produced some extremely wild velocity variations in my guns. When I reduce the loads with this stuff, the velocities remain high and the shot to shot variation becomes much more consistent. One of my favorite loads for my .50 Great plains is 20 grains/vol. equivalent and the .490 ball. It is extra accurate and gets the same low 800 fps velocities as 30 grains of pyrodex p. This current Lemat was getting 700 fps with Pyrodex and fffg from the 30 grain spout and 815f with 777 from a 24 grain spout.
4. Have you had to adjust timing of the LeMat yet? Please describe the process if yes.
The tiny screw on the right side of the frame presses against the internal sear which is a flat, circular spring with a sear on the end. It can be screwed in and out to effect timing.- I guess. I haven't done it. With this revolver, the cylinder bolt drops into the locking points with a "Snap" at full cock and is locking up consistently. It appears somewhat glitchy until I get the grips on and then works perfectly. I won't worry about it until I have to.- Hopefully, never.
5. I have small hands. I positively cannot cock the hammer one-handed. In the Forgett book there are numerous photographs of many different LeMat grip-hammer configurations. Are you aware of anyone altering these configurations? Anyone reducing hammer spring tension/strength?
* Reducing the spring tension would dewat the shot barrel to the point that it wouldn't go off (except occasionally when you don't want it to.) With that short throw, it needs all the whack it can get. My first Lemat had a pretty heavy trigger and this one is lighter. I believe that the first one also had a more massive mainspring but, even so, it was boarderline on shot barrel ignition.
As to the small hands- grip thing- I have medium to medium large hands I suppose and really don't know. I do know that the Hammer stacks and is a bit hard to cock for me too. Best plan is to shift grip get a good thumb contact on the hammer and cock on the downswing.
In the same vein, the grip angle is steep and feels wierd if you are used to shooting just about any other handgun. Once I got past that, I learned that it hangs on target well and actually points very well too. The overall configuration did a lot toward letting me shoot accurate off-hand groups with my First Lemat which had a heavier trigger. I would think with an open mind and a small amount of practice the shooters who consider the lemat awkward and not up to colt standards would find out that the revolver possesses good shooting qualities.
Hope all this makes some sense- I had fun writing it. And by the way, Its been a couple of decades since I've read a Fadala book or magazine article. Does he provide any interesting shooting information on the Lemat?