Minor leading questions

[Bazoo]

I have a Blackhawk, new model 44 spl. With plain based bullets it has minor leading at the beginning of the rifling. It either builds very slowly or not at all. I’ve tried WW+Sn and 50/50 WW:Pb+Sn alloy. Both were about equal in the amount of leading. Both sized .431 with throats larger than this and bore smaller. 50/50 lube and, bullseye powder at special level loads.

My question is, why? Will a softer alloy lead less? Softer alloy would better match the pressure.

It’s not horrible. It’s globular type leading right at the rifling, not really into the forcing cone or down the bore. When I slugged it I felt a very minor resistance there, but shot it to test and this is the result.

I shot a box of cartridges, with each alloy. Both resulted in this leading. The 50/50 alloy was less to start and built up over the box, the ww alloy started with the first cylinder and seemed to decrease as I shot more. Both evened out and didn’t really get into the forcing cone, other than the normal light grey film that brushes or wipes out. I am getting some lead fouling in the chamber forcing cone / lead area before the throats.

In between boxes, I fired some GCed bullets to remove the minor leading, as well as starting that way so as to be an equal test for both boxes. GCed bullets shoot clean of course.

I’m interested in understanding why, I’m not interested in the benefits of powder coating, so don’t bother going down that path.


Bazoo

[sigep1764]

If you slugged it and felt a restriction, my immediate thought would be to fire lap it with JB Bore Paste. Maybe a minor thread constriction after the forcing cone.

[JonB_in_Glencoe]

Thread choke?

[fredj338]

If you are running really light loads, you might try running a bit softer. Did you pull a bullet & see if it got smaller on seating/crimping? Never been a fan of alox, 50/50 or not, but I doubt its the lube at low pressures.

[Dusty Bannister]

"Both sized .431 with throats larger than this and bore smaller."


If your throats are larger than the bullet when sized at .431" you are going to have gas cutting. How much larger are the throats than .431"? A bullet larger in diameter is suggested so it seals in the cylinder throat. Sometimes more information about the actual powder charge and bullet weight will help sort things out.

[Bazoo]

Some of me throats are .4315 and some as large as .4325 from memory. I don’t have my paper handy.

I’ve been running 4.6 bullseye. Bullets were RCBS 44-245-SWC.

[Dusty Bannister]

It might be possible that the RCBS mold will not cast a bullet large enough to size to the diameter you need. Make sure the mold is clean and has no mold release agent in the cavities. Your COWW and tin should give you about the largest casting as long as you are getting good fill out and not significantly over heating the mold or alloy. If they are shiny, cast them slightly frosted. That might increase the diameter a little bit. Measure several with a micrometer to determine the smallest diameter in case the bullets are oval. Apply some of the 50/50 lube with your fingers (NRA 50/50?) and shoot them as cast and see what that does.

It is possible that shooting a soft alloy, soon after casting, means the case tension might be sizing down the bullet after loading. Are you letting the bullets age 3 weeks before loading? You might need to get a larger neck expander to reduce the neck tension. See what this gives you first.

[gwpercle]

Thread choke?

My thoughts also ... that slight restriction at the threads is squeezing them down just enough to make "undersized" . Doesn't sound too bad and lapping could easily solve the problem .

At 44 special velocities / pressure you want a softer bullet , Elmer Keith wrote 1/20 (tin/lead) alloy for normal velocity / pressure boolits .
Gary

[Bazoo]

These bullets had set a year probably. They are .432 or so as cast and are not narrower in any spot.

I’m using an noe expander and it’s of .429 and of sufficient length.

I have a lot of faith in 50/50 lube. All the research I’ve done, and my own experimentation has backed up, that it’s an excellent lube at reducing leading, and works at all pressure levels. It’s messy to work with, but I deal with it.

[Dusty Bannister]

Pull a loaded round and prove to yourself that neck tension is a bit excessive. Or perhaps your crimp is a bit heavy. Photos? I also prefer the 50/50 lube.


https://castboolits.gunloads.com/showthread.php?307783-expanding-pin-size&highlight=adequate+neck+tension+cast+bullets

[mr surveyor]

faster powder, bump up faster?



jd

[Mk42gunner]

I think Dusty had the right answer in post #7. Try a few of your unsized .432" bullets finger lubed. If that cures your leading, get a .432" H&I die.

I've not used 50/50, I got started by making a batch of FWFL and it has served me well so I keep using it.

Robert

[Bazoo]

Thanks for the replies. I’ll ponder it some more.

I was kinda hoping someone could speak from personal experiences. I’ve been through trial and error with several other guns, and all the suggestions didn’t pan out.

[243winxb]

Match groove diameter + .0005" .430" works with .432" throats. My ww get linotype added. 2" off Rotometal bar. I tested it both ways , soft/large & hard/groove diameter +.0005"

44 mag with Unique or W296. Or coat with Alox. When the forcing cone sizes a fat bullet smaller, where does the extra lead go? :?:

https://www.thehighroad.org/index.php?media/44-magnum-hard-alloy-25-yards.3117/fullhttps://www.thehighroad.org/index.php?media/44-magnum-soft-alloy.3118/full