So why can't you shoot lead in a polygonal barrel

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I shot lead Laser-cast reloads in my H&K tonight in a match. No signs of leading in the barrel. Lots of opinions dispensed, most did not hold up under scrutiny. I have a steel match coming Sunday, and will fire 150+ rounds. Is there something I should be watching for my gun to do? Will the accuracy go away? Is your advice from experience or based on rumors. Laser-casts are supposed to be hard lead and resistant to barrel leading. Opinions?
 
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I shot lead Laser-cast reloads in my H&K tonight in a match. No signs of leading in the barrel. Lots of opinions dispensed, most did not hold up under scrutiny. I have a steel match coming Sunday, and will fire 150+ rounds. Is there something I should be watching for my gun to do? Will the accuracy go away? Is your advice from experience or based on rumors. Laser-casts are supposed to be hard lead and resistant to barrel leading. Opinions?
 
SAR,
I'm relying on memory for this (always a dubious endeavor!) but some talk of it being a cumulative effect, barrel dependent. Others I've read, have said that it's when you try to transition from lead, back to to jacketed without stripping the lead out, that things go sideways? Still another contingent says, no trouble at all. So my answer is, I have no direct knowledge one way or the other? But I hate mysteries. And this here joint is the myth busters of the firearms world. So I'll enjoy this one myself!
 
I have two H&K45's one well used, and one unfired until last night-a backup gun. I fired twenty rounds from the new gun and removed the barrel for inpection. It was clean. I then fired forty rounds in a match with the broke-in one, I have not cleaned up the gun yet and I can't comment on leading. I had previously shot the second one with FMJ ammo, maybe 300 rounds.
 
I have a CZ82 which of course also has the polygon bore. My reloads consist of cast Lee bullets with liquid alox for lube. After a few hundred rounds I notice a little lead streaking in the middle of the barrel. As I typically only shoot 100 rds at a time through it in one setting and clean after each session I do not consider this a problem.

If I could find a proper die for my RCBS Lubrimatic I think I could make the streaking go away.
 
I heard that the poly rifleing works like shallow conventional rifleing. It grabs the hard jacket and imparts a spin. Whether the softer lead bullets eapand too much and cause friction or not enough and doesn't spin, I don't know. I doubt if this is a safety issue.
 
OK, this is the deal on polygonal.
Some people don't clean their barrels well and wind up with it loaded with copper and then shoot lead in it. Lead sticks to copper and builds up like crazy with no place to go. Then they try to "shoot it out" with a jacketed bullet and bulge or blow the barrel.

So everybody that sells the polygonal barrels says "no lead bullets!" Wouldn't you?

Some of the Glock shooters that come to the range have never shot anything but lead bullets--but they make sure the barrel is kept clean.
 
Originally posted by OKFC05:
OK, this is the deal on polygonal.
Some people don't clean their barrels well and wind up with it loaded with copper and then shoot lead in it. Lead sticks to copper and builds up like crazy with no place to go. Then they try to "shoot it out" with a jacketed bullet and bulge or blow the barrel.

So everybody that sells the polygonal barrels says "no lead bullets!" Wouldn't you?

Some of the Glock shooters that come to the range have never shot anything but lead bullets--but they make sure the barrel is kept clean.
This is my understanding as well. I know many who shoot lead in their Glocks but be aware that you must monitor for lead buildup.
 
I shot lead Laser-cast reloads in my H&K tonight in a match. No signs of leading in the barrel.
One of the problems with polygonal rifling is that you DON'T see the lead unless you look at it the right way. Just looking from the end of the barrel toward a light and everything looks bright, shiny and clean but run a patch from a lead remover cloth through the bore and it will come out black with obvious streaks and pieces of lead. Take a light and get an oblique angle where you can look at the barrel and you will likely see plenty of lead build up too.

The first time I shot cast bullet out of my Glock 19 I thought the same as you until I took"a much closer look and then spent the hour trying to remove the lead. The only good way was to use the white vinegar and Hydrogen Peroxide mix.
 
That's is good to know. What I'm trying to shoot is supposed to be harder than regular cast lead, and coated. Wouldn't I still be leading up a regular rifled barrel to the same extent? It seems to me that the smooth polygonal bore would lead less. While I gotten some good advice so far on this Forum, I am amazed how many shooters have offered up some very poorly thought out guesses. I figured the manufacturers would have valid reasons for not using lead, but all I'm getting is that they just don't recommend it. I'm just looking a technical explaination of what actually happens. So far the Forum has been more specific than the manufacturers.
 
It seems to me that the smooth polygonal bore would lead less.

Not really. I have "fixed" more than one inaccurate Glock by cleaning out the lead that I could see but the owner could not. Copper is even harder to see. If it looks clean but a little dull, that's copper.

A key difference between rifling types is that the lead buildup in a polygonal bore literally has no place to go, and pressures skyrocket quickly. One local guy was vocal about "just shooting out the lead with a jacketed bullet" until he buldged a barrel.
 
OKF,
Question? Does it continue as an issue for people who clean their weapons thoroughly after each use? Or is it something that appears more often to those pulling a snake through it after, and calling it good?
 
Originally posted by Spotteddog:
OKF,
Question? Does it continue as an issue for people who clean their weapons thoroughly after each use? Or is it something that appears more often to those pulling a snake through it after, and calling it good?

Personally, I've never seen a serious high-volume shooter rely solely on a boresnake or other "quick and still dirty" cleaning method. The guys who brag about how long they go between cleanings should never shoot lead in polygonal barrels. I seriously offended one Glock owner when I suggested the "golden grease" that comes in Glocks was not meant to be permanent.

Copper, or copper and lead mixed, requires serious cleaning like copper solvent and/or mechanical cleaning methods. Foul-out is one way to see how much is really still there.
 
Originally posted by Spotteddog:
Thanks! I do so love having my obsessive compulsive disorder behavior reinforced!
I'm a former soldier. I take professional pride in the meticulously clean state of my weapons.
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Originally posted by Steve C:
The only good way was to use the white vinegar and Hydrogen Peroxide mix.
I'm interested. Please provide details of this.
 
Originally posted by The Big D:
H&K what? My P7-M8 has never had a misfire with any round(s.)

Be safe.

Big D,

I have a p-7 PSP and was always told (advised) not to shoot lead bullets as it could cause problems with the gas collection port. I've shot nothing but factory loaded jacketed bullets without any problems.

Regards,

Dave
 
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