Adventures in leading

[MSD MIke]

Since many ask questions regarding leading and how to stop it I thought I would share my experience with one of my guns.

So, I have a Ruger Blackhawk convertible in 45 colt / 45ACP. New out of the box it always leaded badly with any commercially cast bullet of any hardness at any velocity and with all powders and with both cylinders. The leading occurred mostly in the first part of the barrel right after the forcing cone. Very frustrating

Understanding the “fit is king” I measured the throats and slugged the barrel. Barrel was .451 and the throats were .450. Aha, I said and purchased a reamer and proceeded to ream the throats to .452. Now I am loading .452 bullets, shooting through .452 throats and a .451 barrel. Life will be good. Well, not exactly. Life was a bit better but not great. Leading was reduced some and accuracy was improved but even at a reduced level the leading was more than I considered acceptable.

Powders used have been Unique, 231, Red Dot, and Trial Boss with velocities ranging from 750 FPS to 975 FPS. Always leading. So now I decide to cast my own. I have been collecting wheel weights and have a good supply to work with. I purchased a 250 Grain SWC Lee mold and went to town. Bullets fall at about 257 GR with the COWW alloy I’m using. Bullets are sized to .452 and lubed with 50/50.

Now, back at it with the above mentioned powders and velocities but with my own bullets. It seems like I have made some additional progress but I am still experiencing leading at a bothersome level. I decided heck, it leading anyway so I am going to turn up the wick a little bit and I go for 16 grains of 2400 with my home cast 257GR plain base LSWC cast from straight clip on when weights. The load was snappy and accurate and when I get home to clean up my gun is COMPLETLY lead free. I haven’t shot this particular load over a chronograph yet but I think it should exceed 1000FPS. This is great but the load is hotter than I need to pop cans and shoot paper. I now need to find an 800-850 FPS load that doesn’t lead.

My question is what is the lesson here. Have all my alloys been two hard for the lower velocity loads? It seems COWW have been used by many at lower velocities. Should I try casting a softer alloy out of tape on wheel weight or maybe a mix of tape on and clip on. Some say a slower powder starts the bullet more gently into the rifling but I’m not sure I buy it because my slow powder magnum loads in other calibers have higher velocity than my fast powder loads no matter what the barrel length is. I believe they much be going faster when they contact the rifling. The other school of thought is that the higher pressure of the 2400 load slugs up the bullet and seals the bore better. Anyway, I am looking for advice on getting the slower stuff shooting without leading.

Sorry for the long post, here are the cliff notes

Gun-Ruger Blackhawk convertible-45 Colt/45ACP
Reamed throats to .452
Barrel is .451 with no apparent restrictions
Cylinder gap - .005

Commercial Bullets – Numerous manufacturers products used and they all lead.
Powders used
Unique – Loaded from 850-950 FPS.
231 – Loaded from 785 – 875 FPS
Red Dot – Loaded from 750-850 FPS
Trail Boss – 750 FPS

My own 257gr Plain Base LSWC bullet cast from straight COWW
Lubed with 50/50
All the same above loads still lead but not nearly as bad as with commercial cast bullets
Tried the above mentioned load of 16 Grains of 2400 and everything is perfect but just hotter than I like for fun shooting.

Thoughts?

[detox]

You need a lead hardness tester. Your COWW are probably around 13 bhn (slightly hard) which is why the hotter load obturated to barrel and did not lead. If you want to shoot lower velocities go with a softer alloy such as 20/1 and soft lube.

Most all the 45 cal Rugers have a very slight taper in barrel where it is tightened on frame. This will cause leading more easily than a gun with no taper. Usually softer alloys will shoot better in these 45 cal Rugers (20/1 lead tin 7 bhn on my Saeco hardness tester)

[hemiallen]

Any chance polishing the leade of the throat with JB bore cleaner would lessen lead fouling as well? I have done this on rifles, while determining progress with a bore scope, and it has reduced copper jacket fouling.

Allen

[MSD MIke]

No doubt about needing the hardness tester. Its on the list of things to get. Interesting that most commercially cast bulk bullets are as hard as they are. I wonder just how hard you would have to shoot a 18-20 bhn bullet to get it to work.

Mike

[tomme boy]

Mix your lead 50/50 ww,pure. This should be good to 1000 FPS no problem in a pistol.

[Cherokee]

My most used 45 Colt load in a pair of Ruger OM Blackhawks is with RCBS 45-230CM @ 230 gr cast from COWW +1% tin and lubed with White Label CR, pushed by 5.3 gr of WST or 5.5 gr of 231. No leading @ about 800 fps. Also use in 1866 Uberti LA rifle and Redhawk with no leading. I would think your COWW alloy would be fine but you might try slightly softer alloy.

[MtGun44]

Anothetr vote for softer. You are aleady using a great lube, and appear to have the fit issues
handled. Another thing to try is .453 diam.

Bill

[Shottist]

I have read, years ago, that the barrel can be smaller in diameter where the threaded section is screwed into the frame. If so, this "constriction" can be "fire lapped" out using soft lead bullets fired at low velocity and coated with the proper series of abrasive. I have done this with S&W revolvers in the past with good success. I bought the fire lap kit, with 4 grades of abrasives, from a California company (don't remember the name). Don't know if this will solve your problem, but the lap abrasive will polish your barrel and reduce/prevent leading. I have no leading problem with wheel weight bullets in numerous handguns in various calibers. Keep this in mind if all else fails.

[MSD MIke]

Thanks for the advice guys, my first try will be with softer lead and if that doesn't work I will size at .453 and save fire lapping as a last resort.

Thanks
Mike

[zomby woof]

http://gunblast.com/FerminGarza-Firelapping.htm

I used the pin gauge on my GP100 and had thread choke. Firelapping relieved the choke. I reamed the throats and stopped using LLA. It solved the leading problem.

[390ish]

Yeah, I forgot to quench my 9mm WW boolits last time and it was lead city. All this is a learning process.