Polygonal rifling!

[gunfan2]

Is it safe to shoot Powder coated cast bullets in a handgun with polygonal rifling? I have a new H&K 45CT which has that sort of rifling, I'm assuming that it is ok, but we all know what assuming can do for us!

[sigep1764]

As long as the fit is good, there shouldn’t be issues. Fit is king. Seat the boolit, crimp, then pull it to see if it’s the correct size still. Lubed or coated makes no difference. I’ve shot both through a few glocks without issue.

[Sasquatch-1]

Never had a problem in my Walther PPQ.

[1006]

My HK USP 40 would not shoot moly coated or Berry’s copper plated bullets accurately unless the velocity was kept below 1000fps. The Berry plated bullets literally “flew apart”. I would find several small holes in my target rather than a single round hole with the Berry Bullets.

The 45acp might be a different story, given its low velocity.

The twist rate of the barrel, combined with the rifling type is what I believe created the problem for me (H&K USP 40).

[ioon44]

I have been shooting Hi-Tek coated bullets out of Walther PPQ's (9mm & .45 ACP) for serval years without any problems.

My bullets are 11BHN to 12BHN and are sized .002" to .003" over bore da. Fit is king.

Walther barrels are true polygonal rifling Glocks are not.

I tried Powder coated bullets, Hi-Tek coated is better.

[Half Dog]

That’s one of those issues where some will say yes and others will say no. I would wonder if the risk is worth the reward.

[Sasquatch-1]

I have also fired lead bullets from my .44 mag Desert Eagle which is also polygonal rifling. Other than the fact that they were going too fast to grip the rifling they did not cause any safety concerns that I am aware of. I currently fire only jacket in that gun now.

[Hickok]

I have never had a problem in any of my Glocks after thousands of rounds.

[Super Sneaky Steve]

That’s one of those issues where some will say yes and others will say no. I would wonder if the risk is worth the reward.

You're right, the question comes up all the time and answers differ, but what's the risk? I've never heard of anyone's gun blowing up. Worst case you get crappy accuracy. My Kahr 45 loves them. It's worth trying.

[Delkal]

The Glock warning was because of people who thought Glocks are so perfect and reliable they don't have to be cleaned. So they would put thousands of rounds of cast followed by a jacketed bullet which could lead to problems in any pistol. I think the polygonal / cast warnings are overblown and I have a CZ82 with polygonal rifling and only shoot cast with it. At first I was worried about the reported blow ups so I would inspect the barrel after shooting a few mags to check for leading. Fortunately my load is fine and I can put 300+ rounds at the range and only have the slightest trace of fouling that wipes out easily. YMMV.

[Ed_Shot]

I have never had a problem in any of my Glocks after thousands of rounds.

+1, way back when, I consider I wasted money buying aftermarket barrels for my G22 and 21. Now I have proved to myself with thousands of either lubed or PC'd boolits that Glock OEM barrels work wonderfully with cast.

[Half Dog]

You're right, the question comes up all the time and answers differ, but what's the risk? I've never heard of anyone's gun blowing up. Worst case you get crappy accuracy. My Kahr 45 loves them. It's worth trying.

Risk doesn’t have to be dangerous. If I’m willing to risk $1 on a lottery ticket, is that dangerous?

[Tripplebeards]

I was getting leading with my Glock 20 with my own HPs. Didn’t with ACME boolits. I think I was squeezing them down when I was seating them. I put an extra coat of powder coating over my existing sized Boolits and made sure to flair the bells wider. Never re tested.

[jdgabbard]

Metford rifling (a type of polygonal) was first used with black powder muskets, and later with black powder rifles such as the Lee Metford and Martini Henry. There is no issue with using cast with polygonal rifling. There is a problem using cast boolits improperly sized to the rifling.

[Outer Rondacker]

I shoot powder coated bullets in a G37 45GAP. I have not had any issues. Also used to shoot a G29 in 10mm without any issues.

[elmacgyver0]

Risk doesn’t have to be dangerous. If I’m willing to risk $1 on a lottery ticket, is that dangerous?

It must be the Half part; it would never be an issue with the Dog part.

[fredj338]

Coated bullets are just fine in poly bbls. It is all I run in my Glocks. You can even run lubed lead, just clean the bbl more often. Though I never get great accuracy with lubed lead in poly bbls.

[fredj338]

You're right, the question comes up all the time and answers differ, but what's the risk? I've never heard of anyone's gun blowing up. Worst case you get crappy accuracy. My Kahr 45 loves them. It's worth trying.

A bunch of early LEA G22 got KB using lead bullets. Many dept back then used remanuf ammo with lead bullet for practice. Dont clean the bbl, fire jacketed after & it got exciting.

[kevin c]

Many tens of thousands of commercial and home cast HiTek coated bullets through my Gen 3 polygonal rifled Glock barrels without leading issues.

Now the new, more conventionally rifled Marksman’s barrels, I’ve had leading problems with, but I’m still working on figuring out if it’s the rifling, the machining, bore fit, alloy or coating.

[K43]

...I think the polygonal / cast warnings are overblown and I have a CZ82 with polygonal rifling and only shoot cast with it. At first I was worried about the reported blow ups so I would inspect the barrel after shooting a few mags to check for leading. Fortunately my load is fine and I can put 300+ rounds at the range and only have the slightest trace of fouling that wipes out easily. YMMV.

+1 20 years with a CZ82 and haven't had a problem with cast.

[gunfan2]

Thanks for all the replies, I appreciate the info! I know the Hi-tek coated 230 grain TC bullets shoot extremely accurate through that H&K 45 CT.

[charlie b]

The problem I have with my HK VP9 is not the rifling. There is no throat. The sharp edges of the rifling 'shave' off a bit of the bullet and makes for poor accuracy. Jacketed works well. I suspect if it was properly throated it would shoot cast very well.

Unfortunately HK also 'nitrides' the barrel so using a throating reamer is 'difficult'.

Maybe they put a decent throat on the .45 barrels?

[JiriK]

The problem I have with my HK VP9 is not the rifling. There is no throat. The sharp edges of the rifling 'shave' off a bit of the bullet and makes for poor accuracy. Jacketed works well. I suspect if it was properly throated it would shoot cast very well.

Unfortunately HK also 'nitrides' the barrel so using a throating reamer is 'difficult'.

Maybe they put a decent throat on the .45 barrels?

I kind a ordered HK SFP9 OR already. I guess it is same as VP9.
That is bad news. Does PDP do better with cast bullets?

[charlie b]

Don't know. From what I have read from others the VP9 might do ok with lubed cast bullets. I PC all of my pistol bullets and I suspect the sharp edge to the rifling is scraping the coating.

Every now and then someone reports a buildup of lead at the mouth of the chamber. Others with similar barrels don't report problems. From what I have seen lately many mfgs are not throating their semi-auto barrels.

[Sasquatch-1]

Does PDP do better with cast bullets?

I am guessing you mean the Walther. I have no direct experience with the PDP, but I have owned a PPQ for about 6 or 7 years. I am guessing the barrels are very similar. I have never experienced any lead build up problems with it. When shooting it I generally run from 50 to 150 rounds through it.

[ioon44]

The PDP & PPQ have the same Polygonal rifling.

[charlie b]

Just to clarify, the poly rifling is not the problem, it is the lack of throat. Some get them to shoot ok. I have not.