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Old January 1, 2001, 01:23 PM   #1
Zach Vonler
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I have seen a lot of references to leading by people that imply they can tell if their barrel is leading by examination before cleaning it. I just loaded a lot of lead bullets and would like to know what to look for so I can check at the range between every few rounds. Are there some sort of reliable indicators to look for?

BTW, I'll be shooting .45acp in a SIG 220-1. I know that leading shouldn't be a problem with a 230gr @ 800fps, but I want to be careful. Oh, and the bullets are Oregon Trail laser cast.
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Old January 1, 2001, 04:38 PM   #2
Doug 29
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I doubt that you'll have any leading until you've shot several hundred rounds. I can only spot it AFTER I clean the barrel with wet and dry patches. Then, 10-20 passes with a brass brush and Hoppe's will remove it. I reload and shoot mainly lead bullets.
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Old January 1, 2001, 04:55 PM   #3
Art Eatman
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I wouldn't worry about leading while at the range, unless you're trying for a 1,000-round day. The harder the bullet, the less the leading.

I've shot a lot of pretty soft lead bullets in my 1911s. It's easy to see the leading in the barrel. The normally-sharp lands have "ramps" of lead built up against them. It's worst nearest the chamber.

I bought a little gizmo called a "Lewis Lead Remover". It has a rubberoid cone which is threaded to fit onto a cleaning-rod looking shaft-with-handle. Onto the cone you fit a circular bronze screen (much like a cleaning patch, but very coarse). Pulling this rig through the barrel removes some 90% or 95% of the lead in two or three passes. After that, it's regular cleaning procedures.

Hope this helps,

Art
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Old January 2, 2001, 09:19 AM   #4
tonyz
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Zach

Oregon Trail Lazer-Cast bullets are a very good bullet With
Exellant alloy's which yield good bullet sealing, which in turn reduces or eliminates leading and incresses accuracy.
I suggest that you get the reloading manual from Oregon Trail Bullets, as it has a chapter on understanding bullet obturation and leading, it also cover all aspects of reloading. It is an exellant addition to your reloading manuals.
What I do to eliminate any leading left in my barrel after shooting for the day, is to take 10-15 rounds of Jacketed bullets or Copper plated bullets with me to the range. Then when I am done shooting for the day, I fire the copper bullets, which clean most all lead buildup. Then when you get home you just have your normal cleaning.


Tony Z







[Edited by tonyz on 01-04-2001 at 11:44 AM]
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Old January 2, 2001, 10:55 AM   #5
Southla1
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I remember the old Winchester "Luballoy" .357 Magnum bullets. They leaded so badly that after less than 10 rounds it was almost impossible to see the rifling in the bore. That was back in the 60's. After one box of the I stcuk with reloads using either the old Markell cast bullets of the few jacketed bullets that were arond back then. Compared to back then today is a breeze, both with the selection of jacketed bullets avaliable and the selection of HARD cast bullets avaliable for sale.
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Old January 2, 2001, 01:44 PM   #6
Banzai
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Leading most often shows up as a sort of silver-gray sheen in the bore of the barrel. You sometimes need to look very closely to see it. Under extreme conditions, you can see it as ramps up and down the grooves of the rifling in your bore, obscuring the usually sharp corners of the lands and grooves.
There are several factors that affect “Leading” in a barrel due to the use of lead alloy bullets, either cast or swaged. Also, leading CAN occur when using full metal jacket bullets with exposed lead cores at the base if sufficient pressure/heat is applied.
Lead cast bullet shooters have been conditioned to think that the harder a bullet is, the better it will shoot. For magnum revolvers and cast bullets to be fired in rifles at higher velocities, that may be true. For regular shooting, and even target plinking, extreme hardness is not necessary, and may even be detrimental to accuracy, and show increased leading over those bullets made from softer alloys.
To work, all bullets must obdurate. What that means is that the base of the bullet will expand under pressure and heat to fill the bore. This accomplishes two things, it seals in gas pressure, and it causes the bullet to grip the rifling.
The primary cause of leading is gas cutting, which is the leakage of super heated gas past the base of the bullet and melting particles from it in the process. The particles are then deposited onto the bore like fine plating.
The three factors that affect obduration are gas pressure, hardness of the bullet, and the shape of the base of said bullet. Since we’re talking about lead bullets here, we can safely assume that it’s a flat-based bullet. Low pressures, which is what most lead bullets are loaded to, may not cause a lead bullet of harder alloy to obdurate properly, thus showing up as disappointing accuracy and increased leading. Softer alloys will obdurate more readily, thus showing little or even no leading.
The condition of the forcing cone in your barrel also affects leading. If the cone is rough, it will scrape off particles of the bullet, which will end up in the gas stream. They get superheated, and deposited just as if they were cut from the side of the bullet.
Using a bullet that is the wrong size also affects leading. Too small is obvious, gas cuts around it before it has a chance to obdurate properly. Too large, and it’s like having a rough forcing cone, as the forcing cone is made to “Size” the bullet down as much as .002, shaving off lead into the gas stream. Check your barrel, as the variance from standard is usually +/- .002.
Not to mention that many lead bullets, which are supposed to be sized when they are lubed, are woefully inadequate when it comes uniformity of size. Check a few in each batch, you’ll be very surprised to find that most are quite a bit larger than listed on the box, and consider a simple sizing tool like the Lee to ensure uniformity. The Lee sizer works wonderfully to correct other commercial cast bullets, with little or no mess, although the extra step is an annoyance.
Using hotter powders, or loading to higher pressures will also increase leading. The lead melts from the base, and has the same net effect as cutting. Also, the higher pressures increase the occurrence of cutting, thus negating the benefits of the specific alloy used to make the bullet. Thus, most load manuals show loads that are NOT max pressure, and typically lower than 1000 fps muzzle velocity. Getting much above this “Floor” increases pressures and temperatures to the level where cutting and base melting normally shows up.
If you’re experiencing leading, the typical cures are to try a lower velocity, cooler powder, or softer bullet. Otherwise, you need to look at what you’re shooting. Magnums, or hotter and heavier loads, need harder bullets. Just like every jacketed bullet likes a different powder and charge level in a particular gun, so, too, do lead bullets. It’s just that they’re a lot trickier to play with, and sometimes what you should try next goes against conventional wisdom. That’s why many people don’t use them, or have had negative results. That’s not to say that harder bullets won’t work, just that what I’ve said above is the current conventional wisdom, and we all know that there are always exceptions.
If you’re gonna load lead, be prepared to play with your loads to find the best combination. After all, you do it with your jacket loads, don’t you??

Tom
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Old January 3, 2001, 02:33 PM   #7
Cheapo
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My leading always looks like dull streaks, on both the lands and in the grooves. For some reason, it's usually in the middle of both.

For an interesting exercise, push a dry, tight patch through the bore before applying any solvents. You'll typically see flakes of lead on the patch. Sometimes, that removes half the leading on the first pass!

But its the last 10% of the lead that takes all the elbow grease, IME. What little leading I get with Oregon Trail bullets usually disappears after 20 to 50 strokes of the bronze brush. Most of it's gone after 5 strokes, but it's that last little bit that wants to hang around.

Oregon Trail slugs are FAR easier to clean up after than any "factory" or "reloaded" lead rounds I've ever fired!
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Old January 5, 2001, 09:34 AM   #8
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Banzai, you got it right. I've seen 'hard cast' lead a barrel so bad after a few rounds that it was a smooth bore. On the other hand, I have an 03A3 with over two thousand lead rounds fired and no leading. Size (diameter), alloy, speed, barrel condition, and lube are just some of the variables that must be dealt with. Good and excellent lead loads don't just happen all by themselves. With a matched load it is possible to 'condition' a bore that it seldom if ever needs to be swabbed. sundog
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Old January 5, 2001, 11:34 AM   #9
Southla1
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Sundog, I too have an 03A3 that positivly LOVES that Lyman 170 grain gas check bullet, cast from pure linotype over 41 grains of IMR-4895 (non canister). It chronys right at 2200 FPS, 1 to 2 inche groups at 100 yards (5 shot) and is YET to lead the barrel. Of course it is a hard alloy and is gas checked.
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Old January 19, 2001, 10:50 AM   #10
Tree Rat
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Banzai - Excellent analysis. You spoke about flat base bullets. What effect does a hollow base bullet, in this case the swaged 148gr HBWC, have in obduration, gas sealing and ability to resist lead partical melt? Tree Rat.
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Old January 19, 2001, 01:29 PM   #11
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This turned out to be an excellent topic, brought up some good info.

Banzai,

Excellent post! Very educational, covers many issues I never considered with my load experimentation, as well as refreshing me on some things that I have read about in the past. Its posts like these that make this forum really worthwhile to me.
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Old January 20, 2001, 12:58 PM   #12
johnnybravo
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Treerat, If I'm not mistaken, hollow base lead bullets allow obduration to occur at lower speeds/pressures.
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Old January 20, 2001, 02:40 PM   #13
Banzai
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Johnny got it right.

Tom

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