Can someone explain the lead issue with polygonal barrels? Is this for unjacketed bullets only or something else? I have a Jericho 941 coming, my first pistol, and I'm a unsure. The LCW deal from CanAm is also a package deal with a Glock 17 - which also uses a polygonal barrel. Does this mean I'm safe to order the LCW for the Jericho?
Explain polygonal barrels & their lead issue?
- Thread starter Noltz
- Start date
I shoot lead in mine ...
be aware of lead fouling ...... if you reload keep velocities low ...
these barrels are usually tighter tolerances and you can get pressure spikes ...
I just don't reload lead anymore ...
I like the copper plated bullets ....
much better ....
be aware of lead fouling ...... if you reload keep velocities low ...
these barrels are usually tighter tolerances and you can get pressure spikes ...
I just don't reload lead anymore ...
I like the copper plated bullets ....
much better ....
]
thenewbieglockguy
CGN frequent flyer
- Location
- Ontario (GTA)
Using lead voids the warranty on a Glock FYI.
Polygonal rifling creates a tighter seal within the barrel compared to standard rifling. This means that lead will build up faster in a polygonal barrel. Too much build up will lead to higher pressures as it will seal the projectile/barrel gap even more than usual. As others have said, you can shoot it, just clean it regularly. I only use jacketed ammo though, so my recommendation is not to bother with lead.
I have been shooting lead in my Gen 2 Glock 17 that I have had since 1986. Maybe older Glocks are tougher?
Keep it clean and you will not have trouble. Not sure why Glock would void warranties but I don't remember anything being said back in the 80's about it
Keep it clean and you will not have trouble. Not sure why Glock would void warranties but I don't remember anything being said back in the 80's about it
Cocked&Locked
CGN Ultra frequent flyer
- Location
- S. Ontario
Polygonal rifling is rifling made without the normal land/groove style of twist in the barrel. Imaging that instead of round, the bore of your barrel is an hexagon and they twist it at the rate of normal rifling down the barrel. (or octagon, or pentagon, it's all the same) It's not a new idea, whitworth rifles of the pre civil war period used polygonal rifling, but they had to cut rather then hammer forge so it was much harder to produce.
As suggested above, it's hammer forged and this process tends to give it a very smooth surface finish. The main idea behind it is a forming a highly efficient gas seal, and lower friction twist medium then standard rifling. It also tends to be easier to clean, no sharp corners you have to dig fouling out of, not that this is usually an issue at hand gun velocities. It also tends to have a very long service life.
If you pick a good bullet with a good lube, you'll probably never see any leading worth noting. Too hard a bullet, or a poor lube (too hard) or a lead bullet pushed to fast will start to deposit leading. Because of the nature of polygonal rifling, once it starts to lead, it will begin to lead faster. If it leads enough, you can decrease the bore diameter to the point that the pressure is well above normal due to the added resistance trying to shove a bullet down a smaller hole. This can lead to a kaboom event in the worst circumstances. You have to be pretty oblivious to let this happen, but there are lots of dumb folk out there.
Some like to shoot a few FMJ bullets after shooting a bunch of lead..the idea is the FMJ scrapes the lead out. I don't like this practice, but others swear by it. <shrug>
Go ahead and shoot lead, just clean as it needs it. If your glock is leading up fast, try a different cast bullet. I prefer a softer lead and lube, and have good results.
As suggested above, it's hammer forged and this process tends to give it a very smooth surface finish. The main idea behind it is a forming a highly efficient gas seal, and lower friction twist medium then standard rifling. It also tends to be easier to clean, no sharp corners you have to dig fouling out of, not that this is usually an issue at hand gun velocities. It also tends to have a very long service life.
If you pick a good bullet with a good lube, you'll probably never see any leading worth noting. Too hard a bullet, or a poor lube (too hard) or a lead bullet pushed to fast will start to deposit leading. Because of the nature of polygonal rifling, once it starts to lead, it will begin to lead faster. If it leads enough, you can decrease the bore diameter to the point that the pressure is well above normal due to the added resistance trying to shove a bullet down a smaller hole. This can lead to a kaboom event in the worst circumstances. You have to be pretty oblivious to let this happen, but there are lots of dumb folk out there.
Some like to shoot a few FMJ bullets after shooting a bunch of lead..the idea is the FMJ scrapes the lead out. I don't like this practice, but others swear by it. <shrug>
Go ahead and shoot lead, just clean as it needs it. If your glock is leading up fast, try a different cast bullet. I prefer a softer lead and lube, and have good results.
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I have been shooting lead in my Gen 2 Glock 17 that I have had since 1986. Maybe older Glocks are tougher?
Keep it clean and you will not have trouble. Not sure why Glock would void warranties but I don't remember anything being said back in the 80's about it
Any use of reloaded ammo(outside commercial reloads) will void the warranty, and that includes lead. Its about covering their a$$ in the event some seriously low digit IQ types fail to clean the lead from the barrel after using lead projectiles. It's also to cover their a$$ from the same mouth breathers who can't pay attention when reloading and double charge a round.
TDC
Not an expert on glocks', but I've read that they can fire "out of battery"; ie slide not completely closed. If your reloads are bulged, swollen(glocked), still have flare, or overlength ctg length, may cause a problem. The 1911 style handgun has a builtin safety for this. Inspect and clean your glock regularly with good lead reloads, should be no problem.
Glocks cannot fire out of battery, like all modern quality pistols such events are not possible due to design.
Tdc
I can't prove it but I suspect that the leading up issue in polygonal rifling is related to the idea that there's no hard edge to dig into the sidewalls of the bullet. So with cast lead being softer than the copper jacket the lead can't get a good grab on the rifling. So the lead smears off the bullet and onto the walls of the barrel.
Much the same issue is found with using cast bullets in Marlin Micro Groove rifle barrels where again there's not an aggressive enough bite on the bullet sidewall to lock it in and spin correctly.
Much the same issue is found with using cast bullets in Marlin Micro Groove rifle barrels where again there's not an aggressive enough bite on the bullet sidewall to lock it in and spin correctly.
Thanks for all the replies. Seems the concern is solely when using unjacketed, lead bullets and not cleaning it. I do not have immediate plans to use reloads, but even if I do I just need to be sure to use jacketed projectiles or be aware to clean the barrel often. Everything here sound correct? Any other tips?
correct, accept your still too worried about using lead in a glock IMO. if you cast your own or use commerical cast bullets then simply check the barrel after 10 shots. if it looks like a slight build up, try 50 shots and see how it goes. if you find to much lead then change loads or bullet sizes etc.
I was just about to mention/ask if Canada legal barrels for some Glock models (one manufacturer I'm familiar with is lone wolf) are polygonal or have traditional rifling? Also if they are the latter, would this do away with any issues of using lead ammo in a glock, since you aren't using a polygonal barrel anymore?
I believe all aftermarket barrels have tradition rifling except igb which has a mix between traditional and polygonal rifling ive shot alot of cast in mine (Igb and storm lake) with no issues or any keyhole. Keyhole's is what alot of people experience shooting cast out of polygonal barrels.
