Leading

[Oldagefun]

I'm real new at this but have been reading alot about leading. I want to load my kimber custom ll with 200 gr SWC. Bought them at Missouri bullets. I'll be using Win 231 with Starlite cases and CCI lp primers. Working on the loads now. My questions are:

1) What is leading in a barrel? How do I recognize it and what are the main causes of it.

2) If I do manage to lead my barrel what is the best way to remove it?

Really appreciate all the experts here, I've learned soooo much from you guys.
Thanx

[maillemaker]

Here are some pictures of barrel leading:

http://www.thehighroad.org/showthread.php?t=460747

[jepp2]

Those leading pictures show pretty severe leading. You may have a much lighter version of leading.

If you have significant leading, the Lewis Lead remover works very well. Wrapping a some threads from a pure copper Chore Boy around a brass brush is good to remove the last bits.

Starting with a barrel with no lead or copper will help prevent leading. If you think your barrel is clean, shine a light from one end and look down the other end. You can see the deposits and build up.

[PA-Joe]

Leading is a function of the softness of the lead and the velocity you are shooting it at. That is why lead loads are normally kept below 800 fps. It is also one of the benefits of plated and jacketed bullets.

[Doodlebugger45]

Common causes for leading in the barrel:

Bullet sized too large for your barrel

Bullet sized too small for your barrel

Bullet too soft

Bullet too hard

Velocity too high

Rough or irregular bore


A lot of times, it's kind of trial and error for an individual gun, load, velocity, and bullet size and hardness. I shoot them all the time in my Colt 45. I typically run velocities up to about 900 fps so I use cast bullets with a hardness of around 12 for that one. For my .44 mag, I shoot loads at about 1100-1200 fps so I use harder bullets, about 18 or so. Same way for the .357 loads. They run at around 1250-1300 fps so I use bullets at about 18 BHN. No leading. But for my .480 Ruger, those loads can get up to 1400 or more, so I use a gas check on the cast bullets, and they are pretty hard too. So far, I haven't tried cast bullets in the .454 Casull, but other people do it all the time with velocities over 1500 fps.

[BDS-THR]

Missouri Bullets Facebook "Discussions" page has a nice article on leading:

Leading Defined
By Jim Taylor

Leading is: Deposits of bullet alloy that have been smeared into the surface of the gun's bore. In extreme cases, it will build to the point where the rifling is completely choked with deposits and the barrel appears to be smooth-bored. Once leading begins, it will have a tendency to strip alloy from the next bullet which builds the deposit with the next shot. Each successive bullet fired will "iron" the lead into the surface of the bore and make it more difficult to remove the deposit.

Chamber and Forcing Cone Leading
This is normally caused by shooting a bullet that is too hard (BHN too high) for the velocities used. Either use a softer alloy, or increase the charge (within published loading data, of course!) to correct this problem. This can also be caused by shooting a bullet that is too small in diameter. Revolvers will lead in the chamber and forcing cone while closed breech weapons will lead in the chamber and the beginning of the rifling area. You should measure the cylinders for revolvers and size the bullets to them, not the bore (unless the bore is larger than the chambers, in which case the problem will have to be corrected by a gunsmith or the factory) and measure the bore in closed breech weapons to determine proper bullet diameter. Rule of thumb says the bullet should be .001" larger than the bore or equal to (or very slightly larger than) cylinder diameter in a revolver. If the alloy is soft enough, you can get away with a slight "push fit" in a revolver cylinder, but certainly the bullet should be large enough to not fall through the small diameter portion of the cylinder freely!

Breech Leading
This is lead fouling that begins in the rifled portion of the bore, but after the chamber or forcing cone, and extends into the bore for a distance of up to several inches. This is normally caused by shooting a bullet that has a low BHN (too soft) for the pressures or velocities used. The bullet will actually strip as it enters the rifling as it does not have the strength to properly engage and begin rotation due to the forces pushing it through the barrel. It doesn't mean it's a bad bullet alloy, it just means you are driving it too hard. If you want to go faster, you will need a stronger alloy with a higher BHN number. Alloys must be used which fit the application. There is no such thing as a "magic" alloy that works for every single application!

Bore Leading, Muzzle End
When lead fouling occurs at the muzzle end, you have run out of bullet lubricant. Either use a better lube, or more of it to correct the problem. If you can, use a bullet with more, or deeper and/or wider lube grooves. After firing a box of cast bullets, say 20 to 50 rounds, there could be a lube "star" on the muzzle. This indicates that there is simply left over lubricant and the bullet exited the muzzle with plenty of lube. If, however, you find a lead "star" instead you need to try something different as the bullet ran out of lube. You may be able to simply reduce the charge (lower velocity) and correct this. The alternatives are use a better lube or a different bullet design that can carry more lube. As an example, there are .45-70 Govt. 405 grain bullets on the market with only a single lube groove. Barrels over 16"-18" long using this single lube groove design bullet will exhibit muzzle leading after only a few shots! Frankly, the only reason this bullet exists is that it is simple to manufacture!

Bore Leading, Entire Bore
Normally, this is caused by shooting a bullet that is too small in diameter for the bore. If the bullet doesn't seal the bore, gas will be able to escape past the bullet causing a cutting action similar to the way a cutting torch cuts steel. By the way, gas cutting will only occur if gas can flow. If it flows, what you have in effect is leak. The bullet is not sealing the bore.
The burning propellant will not melt the base of a lead bullet! There is simply too much physical mass to heat to the melting point of lead (about 600-700F) in the short time a bullet is exposed to the propellant gas to bring it to it's melting point! If you want proof, examine wads used in shotguns or black powder cartridge loads after firing. They may show slight darkening, but won't be consumed in flames either! If the burning powder won't melt the plastic or burn up the cardboard, why would it melt a bullet base? The answer is, it can't.

Some years ago my Dad and I ran tests to see if heat could actually melt the bullet bases. We used .357 and .44 Magnums as the test vehicles. To the bullet bases we glued flash paper, the kind magicians use. No matter which powder we used, we were never able to ignite the flash paper. We also put low temperature wax on the bases of the bullets and again were unable to get any wax to melt. As was said already, if you can't melt the wax you sure won't melt lead.

Damaged bullet bases are caused from other things, principally incorrect bullet fit to the bore or a bad bullet to begin with!

Optimum Accuracy
Cast bullet accuracy is directly related to the pressure levels your cartridge is loaded to. If the operating pressure is too low relative to the bullet's BHN (hardness), you will not achieve obturation and the bore will not seal. This will cause gas leakage and erosion (gas cutting) that causes leading at low pressure and low velocity! Optimum accuracy occurs at a point just below the pressure levels that induce breech leading for a given bullet alloy. In other words, if you are shooting an excessively hard bullet for Cowboy Action pressure levels, you will get leading, usually in the forcing cone or chamber area.

Optimum Bullets
Use a bullet of proper alloy for the velocity you are shooting. Many shooters today are using bullets much harder than is called for. In addition use the best lubrication you can get. These three things, proper fit to the bore, proper hardness for the velocity/pressure, and proper lube can make shooting cast bullets an enjoyable time instead of a headache.

[reloader28]

PA-Joe
I disagree with you on that. I shoot alota air cooled WW bullets going alot faster than that. Pressure and fit has way more to do with the load than speed does.

[overkill0084]

http://www.brownells.com/.aspx/sid=1...100036_d_10190

I shoot a lot of 230 gr Missouri bullets out of my Spingfield Armory 1911 (mid-range charge of bullseye). I haven't had any leading problems. That picture was an extreme example of what not to do with cast. Every now & then I find a slight bit of lead residue, Nothing a normal brass brush+Hoppe's can't fix. If you wish to push to higher velocities, puchase the Lewis Lead Remover, just in case.

[Edward429451]

I have to disagree with PA Joe also. I push cast way faster than 800 without leading. Bore fit and hardness.

[wncchester]

Avoid leading with bore fit, hardness AND a good lube. If you want to avoid leading use the old NRA formula lube, 50:50 Beeswax and Alox.

Lots of ways to remove lead from a bore but just pushing a good condition bore brush through the barrel enough times will do it. I once cleaned the bore of a 6" .357 that had been leaded so bad the riflling didn't show, the owner thought his barrel was totally shot out! Took about 30 minutes to completely clean it. (Got to prevent letting the rod rub against the sides of the bore to avoid accuracy destroying wear.)

[maillemaker]

The single biggest contributor to leading is lead.

[BDS-THR]

I get very minimal leading at the chamber end shooting Missouri Bullets 9mm, 40S&W and 45ACP bullets (Lone Wolf barrels for 9mm/40S&W and M&P factory for 45ACP). I get no leading in stainless steel Kimber barrels for 45ACP.

What little fouling/leading I get, they are removed easily with old bore brush wrapped with copper scrubber like Chore Boy dipped in Hoppes #9. Few strokes and barrels are clean.

[IllinoisCoyoteHunter]

As already stated, it is all about proper fit. If the bullets "fits" (meaning it is generally 1-2 thousandths over groove diameter), you do not need to be as picky as how "hard" your alloy is. Harder is NOT always better. I shoot air cooled WWs over 2200 fps in my 454 casull (using a gas check, of course... ). Generally, I can get to about 1250-1300 fps without a gas check and no leading (although pressure is a better gauge for when a gas check is needed, IMO). You will know when you have leading, trust me. COPPER....COPPER....COPPER Chore boys will de-lead any barrel quickly. Peel off a few strands and wrap around a cleaning brush so the fit is nice and tight in the barrel and you will be good to go. Did I mention to make sure it is a COPPER chore boy?

[PA-Joe]

I understand that you can shoot lead bullets at more than 800 FPS but then you have to cast special alloys or use gas checks. The new reloader may not have a good enough knowledge about casting bullets to shoot above 800 FPS.

[IllinoisCoyoteHunter]

I understand that you can shoot lead bullets at more than 800 FPS but then you have to cast special alloys or use gas checks. The new reloader may not have a good enough knowledge about casting bullets to shoot above 800 FPS.

Once again, I disagree. I believe that this common misconception is the reason why alot of shooters don't cast their own or shoot cast bullets. I guess that just leaves us more lead to shoot....

[Hog Buster]

I’ve been shooting cast WW, no gas check, at max load of 296 in my Model 29 for years (1200 fps or so) and never any leading.

Hot? Yes... Accurate? Not so much... Fun to shoot? Definitely.....