Leading in revolvers with top loads

It seems that maximum load data within SAAMI specs can be found in loading manuals. That would be the first place to look, and is probably where people here found their data.

I have shot well lubed cast lead bullets for decades and hardly ever experienced a problem with leading, even at max 44 Magnum and max 357 magnum loadings.

In my experience, leading - results more often from cylinder, bore, bullet size and hardness issues - than from the bullet lube.

I've done well powder coating, then sizing.

MP 432-265 SWC (H&G #503) I have used this same bullet extensively in .44 Magnum revolvers up to 1300 fps with zero leading when sized for the cylinder throat dia's plus 0.001". My Rugers take a 0.430" dia bullet, two Smith .44 Mags prefer a 0.431", and my Marlin 336 in .44 Magnum needs 0.432"-0.433" to do its best. I've had good luck with 2400, Acc #9 and even Unique and Herco. I have both the penta and round hollow point pins for my triple mold and have found that a 50-50 mix of wheel weights and pure lead will give some healthy expansion when pushed to 1200 fps. The HP's are a bit more difficult to cast, soft as they are, and do bear a good scrutiny for culls, but the good ones would make a terrific close-in handgun deer load...say out to 35-40 yds.

In the Marlin, I've pushed the MP design a bit harder, but have not chrono'd the results. l suspect it's ~1500 fps. The alloy I've been using over the years, has always been air cooled wheel weights with ~2% tin for better mold fill out and I lube with 50/50, alox to beeswax. The Marlin has a Micro Groove bbl., by the way, and still gives good, deer killing accuracy out to ~75 yds, with 50 yd accuracy running ~ 2", and will hold up for a 5 shot group too. This is with a 2.5x scope mounted.

I've also used Lyman's version of the old Thompson designed 429244 GC and 429215 GC sized the same as my MP mold. Both Thompsons will give ragged hole accuracy in the carbine and sub-2" groups from the handguns at 25-30 yds. Too, the gas check allows a softer alloy (50-50) WW to lead, while giving equal accuracy and potentially more expansion on game.

The Lyman/Thompson 429215 GC, is my personal favorite in the Marlin as well as my handguns, as it's economical with my dwindling supply of wheel weights, and gives lower recoil in the revolvers. Also, If you're looking for a good .44-40 bullet, this one might work out for you & has worked extremely well with my son's 1925 vintage Winchester M-92 rifle; even with it's pitted bore. It feeds well in my Marlin 336, #2 son's Marlin 1894, and #1 son's Winchester 92.

HTH's Rod

Recovered bullets that have the lube grooves still full.... should tell you something.

Lee Liquid Alox, 100 bullets in a jar with a lid half a teaspoon of liquid alox shake well, pour the bullets out into a beer tray the thin coating will need to dry overnight..

leading will be reduced or disappear.

I haven’t tried casting, but whatever size, lube and tin combination MB bullets use for their .500 mag 400 gr crushers at 18 Brinell result in a super accurate, non-leading formula at maximum published H110 (39 -40) load levels when shot through the PC 3.5” S&W. Not a scientific approach to accuracy measurement but 2 out of 5 shots with this combination will blast 1 gal water jugs at 100 yd off-hand. Expecting 1400 to 1500 muzzle (still waiting for ideal opportunity to chrono these)


CAUTION: This post includes some loading data which may be considered beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK.

My best "heavy" .44 Magnum load is one cribbed from Ross Seyfried decades ago. I use a 325 grain LBT LFN, cast of WW, usually sized to .430 or .431 (just slightly larger than the throats of the particular gun) and lubed with LBT blue soft. The powder is H110, 21 grains. (This is a grain less than Hodgdon's max, but like Ross, I have found that 21 grains tends to give much more consistent velocities.)

With a 7.5 inch barrel the load averages about 1300 fps. Accuracy usually is as good as the guns seems capable; about 1" per 25 yards - although of course there is a lot of individuality.

I generally use LBT Blue soft for everything except blackpowder. I am really not sure if there is any magic to lube, ie. one brand that is significantly better than another. I do believe that softer is usually better and have had most of my really bad results with hard commercial lubes - to the point where I believe that hard lube is more beneficial to the bullet maker than to the shooter. Otherwise, I'd be surprised - happy, but surprised - if anyone can come up with a lube that is head-and-shoulders above everything else.

For my money, bullet fit is 90% of the solution, and bullet hardness is about 8%. Lube - along with phase of the moon and mood of the handloader - makes up the balance. Good luck!

<edit> And just to try to provide all of the info the OP requests: My most used .44s are Blackhawks with 7.5" barrels. I honestly have no idea what my OAL is; it's whatever the cartridge comes to when the bullet is crimped into the groove. And I simply don't put up with significant leading anymore, so have no answer for the question about how long the guns can go without it. With a properly fitted bullet of correct hardness and decent lube, fired in a gun with correct dimensions, I expect to see a light "frost" of lead after the first five or six rounds, and I then expect that same bore condition to be maintained for all subsequent rounds.