Extreme hard cast bullets and leading

[PapaG]

Thought I'd share an experience with you all. Had a chance a few years back to buy a couple thousand hard cast 44s, all from a Lyman 429421 mould and lubed with one of those crappy blue wax lubes. Loaded them up to the same level as I had with my own cast bullets using wheelweights, alox/beeswax formula lube and my personal favorite load of 2400. Leading plus, in my Stainless Super Blackhawk, my old 29-2, and my Contender. Not a happy camper. Finally got them cleaned up and went back to my wheelweight/alox bullets. Same load, same guns, virtually no leading. Fifty rounds produced a few light streaks just ahead of the forcing cone.

My theory...too hard, not slugging up to fill the chamber throat and thus gas cutting and leading. Just hard enough, slugged up to fill the throat and no real leading. Also, alox/beeswax, while stinky, seems to lube better.

Your thoughts, guys?

 

[35 Whelen]

MY guess would be the bullets may be undersized. Have mic'ed them? Have you slugged your barrel(s) and the throats of the cylinders?
I shoot straight WW and usually a kind of gooey homemade lube, size bullets .001" over groove size. My K-31 match loads run 1400+ fps and I shoot almost 100 rounds per match and have never had any leading. Same with my 03A3 except I size them .002" over groove. Again 1400+ fps, 95 shots fired in one day, and no leading.
That's my take!
35W

 

[zxcvbob]

Oregon Trails LaserCast bullets are ridiculously hard, but I've never had any leading with them (I can't afford them anymore but I used to use them)

 

[Hunt480]

My experience has been finding which powder to use with a particular cast bullet. For instance, in my 44 SRH the Lasercast would lead my gun badly when I used any load of Unique but I found a load with IMR4227 that does'nt seem to lead at all and is very accurate. I'm assuming the hotter powder was causing the leading in this case.

 

[ArchAngelCD]

There are many reasons for leading, too hard a bullet for the load you're shooting is only one of them. (but it is one of the reasons)

 

[918v]

PapaG,

Your experience mirrors mine with hardcast bullets in a S&W 625 45 ACP.

 

[MMCSRET]

I've had the same general experience with "hardcast". I cast for all my handguns but on occasion I have used commercially produced cast bullets. I got leading from them in most all my guns with about any load combination I tried. The best commercial bullets I ever used were from Cast Performance Bullet Co. when they were in Riverton Wyoming. I prefer plain base bullets and theirs were great. My own cast work for me and they are soft, very soft by some standards. I mix wheel weights and plain lead at a 50/50 ratio for most. Some I mix even softer. Hard may work, but mine work better. I never make any of my bullets harder than air cooled wheel weights; they work in all my magnums and some carbines.

 

[PapaG]

Same diameter as mine, .430. I can go down to .429 with my own and get great results.

 

[NuJudge]

Right after bullet size, I'd suspect the quality of the lube. As a test, can I suggest you clean off the lube from those purchased bullets, relube them with 50% Alox 2138F/50% Beeswax, and then try them again.

Some time when SWMBO is out of town, you might want to oven anneal some cleaned bullets. Put them on a sheet of metal, heat them up to about 400 degrees, then turn off the oven and let them slowly cool.

Really, I'm a believer in hard bullets. I water drop all my cast bullets, as much to ease handling of freshly cast HOT! bullets as to get them hard. I like them a bit over groove diameter.

 

[P-32]

You can also get leading when you don't bell enough.

 

[Walkalong]

I used to shoot some extremely hard "heat treated" cast bullets in "Ruger Only" loads with no leading in a Blackhawk. It happened to have throats sized perfectly for the bore, and the bullets fit the throats tightly.

As ArchangelCD posted, there is a lot more to leading than bullet hardness. They can be too soft, too hard, the wrong size, the throats can be undersized, the bore oversized, or a combo of any two or three of those things.