Barrel Leading Questions

[That Guy]

I just started casting my own 9mm and I have a two related questions about leading.

First, what's the big deal if I get a little leading in the barrel? Will it effect how the gun shoots or what is the issue?

Second, sort of related, if you are getting leading, does it sort of reach a plateau? Is there a certain amount of deposits that will build up or will it just get progressively worse?

My first batch didn't leave any lead in the barrel, but I'm sure at some point I will screw it up. Just wondering what the big deal actually is.


I've searched NES and the internet in general, but I just can't find an answer these questions.

 

[Bob J]

Leading will significantly effect your accuracy..... The more leading the worst the accuracy.... It will stop leading when your barrel is effectively a smooth bore....

 

[kayak1]

This thread will help you.
http://castboolits.gunloads.com/showthread.php?121607-Setting-up-for-boolits-in-a-new-9mm

My first question would be have you slugged your barrel and if so what size is it and what size are you bullets?

 

[That Guy]

I didn't slug the barrel yet. I had read that most 9mm barrels are pretty close and generally work well with standard .356 molds (and, so far it seems to have worked). I used a Lee TL 124 grn mold, tumble lubed with Lee Liquid Alox. Seems to have worked ok - I'm more concerned with when I move into .45 casting.

Thanks for the link - I'll read through that thread tonight.

 

[asp]

You said your first batch didn't lead? Was your batch bigger than 10? In my experience, if I haven't seen leading in 10, I won't see it at all.

If you do encounter it on a load that should work (not overly hot), the factors, in order, that I have come to suspect of being wrong are:

bullet diameter
Alloy
Lube
Charge
The barrel (ream the throat)

As others have said, ruins accuracy and will continue to build up. But at a certain point the gun becomes unsafe to shoot. Lead building up in the barrel also means the bullet has to get pushed through it, causing an increase in pressure in the barrel. It's probably not as big of a deal for middle of the road loads but I wouldn't let it go on loads that are already at or near the max.

 

[kayak1]

I didn't slug the barrel yet. I had read that most 9mm barrels are pretty close and generally work well with standard .356 molds (and, so far it seems to have worked). I used a Lee TL 124 grn mold, tumble lubed with Lee Liquid Alox. Seems to have worked ok - I'm more concerned with when I move into .45 casting.

Thanks for the link - I'll read through that thread tonight.

I size my 9mm to .357 as my M&P slugged at .356. I am sizing with a star and using lsstuff.com Carnauba Red it's $1.80 a stick plus shipping. If you order 100 it works out to less than $1.80 per stick including shipping.
http://lsstuff.com/store/index.php?main_page=product_info&cPath=1&products_id=12

With this setup I just end up with a bit of powder residue to clean as I haven't been able to get my hands on anything cleaner than tite group in some time.

If you want me to send you some of the 9mm I have cast and sized please drop me a PM with your address.

With 45 I have been sizing to .452 for my M&P.

Good luck getting things worked out!

 

[mac1911]

9mm has been my only problem child. I gave up. slugged .356 I used .356 and a 357 mold. LLA and LSS lube also. Barrel gets lead from end to end.... 45 was no problem at all until I tried mixing a harder alloy vs straight wheel weights. leaded up the muzzle end pretty good. switched back to straight wheel weight alloy and LLA been fine.

 

[highscore]

9mm has been my only problem child. I gave up. slugged .356 I used .356 and a 357 mold. LLA and LSS lube also. Barrel gets lead from end to end.... 45 was no problem at all until I tried mixing a harder alloy vs straight wheel weights. leaded up the muzzle end pretty good. switched back to straight wheel weight alloy and LLA been fine.

We tried casting in 9mm for XD's. Five pistols and they all loaded, very badly. Only tried a few lubes but bumped the diameter of the bullets up to .359. Only one barrel puts up with lead and it was only when sized to .359, some loading but at least it grouped. I've had cast bullets keyhole on the first round in a clean barrel. If I were to try cast bullets again, it would be with a replacement barrel not made by Springfield.

 

[mac1911]

We tried casting in 9mm for XD's. Five pistols and they all loaded, very badly. Only tried a few lubes but bumped the diameter of the bullets up to .359. Only one barrel puts up with lead and it was only when sized to .359, some loading but at least it grouped. I've had cast bullets keyhole on the first round in a clean barrel. If I were to try cast bullets again, it would be with a replacement barrel not made by Springfield.

Is 9mm a "problem" for cast in general? I must be lucky as my 38/357 lee mold does fine in all my revolvers....i get a little leading in the "throat" whern I use 38s in my 357. it takes about 300rnds for a build up be seen. I clean it every 100 rnds as I do shoot 357 out of it also. If I go to long the cylenders get gunked up and 357 cases wont seat in the cyl. No issues in my 45s,32sw or my rifles. all straight WW lead

 

[Gammon]

I have witnesses some problems with European 9s. Seems like those folks can't agree on what diameter 9mm is.

 

[jpm]

I have witnesses some problems with European 9s. Seems like those folks can't agree on what diameter 9mm is.

some of them use polygonal rifling which doesn't play well with lead either

 

[Patriot]

I never had a leading problem that correct sizing of the bullet didn't cure completely. I never played
around with my mix to cure a leading problem. My standard mix is a little softer than Lyman #2.

 

[highscore]

Is 9mm a "problem" for cast in general? I must be lucky as my 38/357 lee mold does fine in all my revolvers....i get a little leading in the "throat" whern I use 38s in my 357. it takes about 300rnds for a build up be seen. I clean it every 100 rnds as I do shoot 357 out of it also. If I go to long the cylenders get gunked up and 357 cases wont seat in the cyl. No issues in my 45s,32sw or my rifles. all straight WW lead

I do believe that 9mm is a problem but especially with Springfield. I attended the casting workshop a few years ago and went home with some very nice (actually the best I had ever seen) hollow points. First round keyholes out of a clean barrel. The others did as well. The owner of the mold sent me some more of them in case something was wrong but they keyholed as well. Every bullet made of lead leads the barrel the full length. Every jacketed round shoots in tight little groups. My SA barrel and others I've dealt with are just too loose for lead or possibly it's the shape of the rifling. Personally I think that the looseness of the barrel keeps the combustion from being sealed and goes around the bullet. If I want to shoot lead again, I'll change to an aftermarket barrel.

 

[Gammon]

some of them use polygonal rifling which doesn't play well with lead either

It has been my experience the polygonal rifling works just fine with hard cast lead bullets. The problems with this type of barrel seemed to coincide with the arrival of the Glock pistol on the market. H&K introduced a .45 ACP pistol with this rifling in the seventies which handled lead bullets ok. I think the real problem is barrel vs bullet diameter.

I had no problems with lead bullets in 45 and 40 in Glocks I have owned. They weren't perfect but would easily go 300 to 400 rounds between cleaning. I then tried a 9mm Glock and had nothing but trouble; key holing at 25 yds and horrible accuracy with 130 gr industry standard .356 hard cast lead bullets at about 1000 fps. As an experiment, I loaded the same bullets in .357 diameter at the same velocity. Key holing stopped and accuracy improved to a 4 in group at 50 yds. Obviously the 9mm Glock barrel needed a larger than standard 9mm bullet for optimum performance. Unfortunately the Glock wasn't mine so I never had a chance to check its propensity for leading.

 

[Gammon]

Mistake

 

[jpm]

I had no problems with lead bullets in 45 and 40 in Glocks I have owned. They weren't perfect but would easily go 300 to 400 rounds between cleaning. I then tried a 9mm Glock and had nothing but trouble; key holing at 25 yds and horrible accuracy with 130 gr industry standard .356 hard cast lead bullets at about 1000 fps. As an experiment, I loaded the same bullets in .357 diameter at the same velocity. Key holing stopped and accuracy improved to a 4 in group at 50 yds. Obviously the 9mm Glock barrel needed a larger than standard 9mm bullet for optimum performance. Unfortunately the Glock wasn't mine so I never had a chance to check its propensity for leading.

That's interesting. I had a similar issue with 40 cal in a polygonal barrel. Before I finished a magazine of lead bullets, they were keyholing at 50' or less no matter if I went slower or hotter, different powders, etc. I wonder if a larger bullet would have fixed that problem, unfortunately the gun is gone now but definitely storing this in the memory bank for future reference.

 

[dcmdon]

The hot ticket for clean up after the fact:

http://www.brownells.com/gun-cleani...ead-remover/lewis-lead-remover-prod21587.aspx

 

[Gammon]

That's interesting. I had a similar issue with 40 cal in a polygonal barrel. Before I finished a magazine of lead bullets, they were keyholing at 50' or less no matter if I went slower or hotter, different powders, etc. I wonder if a larger bullet would have fixed that problem, unfortunately the gun is gone now but definitely storing this in the memory bank for future reference.

Generally speaking, the problems you have encountered are almost always due to a mismatch between bullet and barrel diameter. I have had the good fortune of a supply of cast bullets in a variety of diameters to experiment with. When a lack of accuracy raises its ugly head, I try the same load with a bullet with a slightly larger diameter. Increases of diameter of as little as .001 have cured the problem.

 

[DukeInFlorida]

It takes a minimum of three things being right to avoid leading in your barrel:
1) proper hardness of the lead alloy used for casting. During firing, the lead bullet needs to be able to expand a bit to just properly fill and seal the lands and grooves. Too hard and hot gases will jet past the bullet, causing leading. Too soft, and lead will smear and wipe onto the gun barrel surface.
2) Proper sizing of the bullet. In order for the sealing that happens in step one (presuming you used a proper lead hardness) to be effective, the bullet needs to be the proper size. Typically .001" to .002" larger than bore size is where you want to be. That number varies depending on other factors, including the type and size of the lands and grooves in your barrel.
3) A proper lube. Without a proper lube, even a bullet with good lead hardness, and proper sizing will lead the barrel. Typically, the faster the bullet goes, the harder the lube needs to be. The point is that there needs to be enough of the lube, in the right places on the bullet, for the bullet to be lubricated for the ENTIRE trip down the barrel.

I would encourage you all to read Glenn Fryxell's article on this very subject. He covers it well, explains how and why, and gives you good ideas for success.

You can get a copy of it here:
http://www.lasc.us/Fryxell_Book_Contents.htm