glocks and cast bullets

[luober]

Do all Glock handguns have a polygon type bore,and is the rumor that they do not handle (accuracy) cast bullets as well as a conventionally rifled barrel true? What semi-auto handguns seem to have the most "out of the box" accuracy in 9mm and 40S&W? Thanks

[Hunter]

It is not that the polygonal rifling does not handle lead well but you should not shoot lead out of them at all.
Lead build up is much more drastic in the polygonal barrel and an over pressure situation can occur.

[35remington]

This should get interesting, again.

[9.3X62AL]

If we paid attention to all that is written in gun manufacturer operator's manuals--cartridge reloading would be non-existent. I'll leave it at that. Sell off the Dillons, give away the Rockchucker, use the Lyman 450 to make suppositories. Sell all that wheelweight alloy, too.

[Hunter]

What I posted is what I have been told by a few folks who shoot Glocks and reload (one who took the Glock armors class). I do not own a Glock so I have never researched it for myself.
I also understand shooting lead out of a Glock will void the warranty

[dubber123]

So Al, how many rounds of lead have you got through your Glock .45 now anyways?

[9.3X62AL]

Shooting anything other than factory ammo out of just about all firearms voids their warrantees. On paper. How closely the respective factories hew to that rubric varies.

Buckshot owns a muzzle loading rifle that has a lot more "polygonal" rifling pattern than the ovate hexagonal in the Glock 9mm/357 SIG/40/10mm barrels, or than the octagonal ovate Glock 45 ACP form. The name of it escapes me. His rifle shoots pure lead elongated slugs over black powder, with fine accuracy.

Similarly, I have a Glock 21 with factory barrel in place. I have fired target SWC (Lee H&G #68 copy, Lyman #452460) RN lead castings (#452374), and the BD 45 boolit. Velocities ran from 725 FPS to well past 900 FPS, sizing was at .454" and at .452". Alloy was 92/6/2, lube was Javelina. Try as I might, I cannot get the Glock barrel to form lead deposits.

Lead-friendly 9mm....Springfield Loaded model, or an old Colt Series 70. Both use 1-16" rifling twist, instead of the usual 1-10" or 4 turns/meter. Lead-friendly 40 would be the CZ-75, again due to its slowed twist rate (1-16). Fast twists and high pressure are rifle characteristics carried over into the handgun world by the 9mm and 40 S&W. Make sure the boolits fit, and life should be good. Both the 9mm and the 40 S&W are problematic calibers with lead boolits in any platform, and the teenage mutant mall ninjas that spout the drivel about Glock barrels being unsuitable for lead boolits strike me as the types with too much confidence to have actually experimented with the subject--and too little experience to know any better.

[Hunter]

and the teenage mutant mall ninjas that spout the drivel about Glock barrels being unsuitable for lead boolits strike me as the types with too much confidence to have actually experimented with the subject--and too little experience to know any better.

No disrespect intended but was that comment aimed at me?
Though what I posted may or may not be incorrect I have heard that from folks who are qualified to have an opinion and I was merely trying to help.

[waksupi]

I see Al has chimed in here. Seems like just recently, he gave a real torture test to find out about this. I can't recall reading anything about his pistol blowing up, or getting leaded. Once he gets another 20-30,000 rounds down range, I am sure he will let us know how many times it has blown up!

[9.3X62AL]

Not at all, Hunter. Not at all. Glock enthusiasts seem to have 2 traits in common--1) under 30 years of age and 2) few if any other pistols in their safe, and relatively light experience levels. It is this sort of shooter that normally advances these opinions about reloads and lead boolits in Gaston's Gaspipes. You don't strike me from your post traffic to be that sort of shooter AT ALL.

Attendance at a Glock armorer's school may or may not indicate skill and/or knowledge, but I can practically guarantee that attendees were beaten up over the reloaded ammo question. It's almost a mantra.

[Hunter]

Excellent! I do not want to ruffle any feathers and I will freely admit my information was from Glock shooters (which I reckon validated your point).
I do not care for Glocks so I have no first hand information except for a handful of range trips where in the interest in broadening my horizons I tried a few different models.
I learned something new. I reckon I will not jump the gun (pun intended) before I post second hand information.

[versifier]

This is one thing you need to understand about Glocks. The earlier models had chambers that are oversized so they would feed anything, and the case webs were poorly supported. With high pressure rounds like .40 or 10mm, the cases would form dangerous bulges when fired, weakening them considerably. When reloaded, they have a much increased chance of rupturing upon firing, and this caused a lot of KABOOMs. Supposedly, the newer ones have better support in the web area. This does not happen with the .45, which works at a much lower operating pressure, and it is no big deal to reload brass that has been fired in a non-Glock. As to the polygonal rifling building up lead, I have not noticed it in either 9mm(G17), .40S&W(G23), or .45ACP(G21), but I don't shoot anything softer than ww's.

[9.3X62AL]

Hunter, it's all good here. If the board stands for anything, it is that there are very few "absolutes" in the world of cast boolit shooting.

Urban legend said that Marlin Microgroove barrels were unsuitable for lead--many folks here shoot castings in MG barrels with fine accuracy.

Same deal with lead boolits in Glocks--if the boolit fits, and is reasonably hard for the caliber/application and properly lubed, it will shoot well and safely.

2200 FPS was once thought to be the upper limit of cast boolit velocity with anything resembling accuracy.......a number of folks here run castings well past 2400 FPS with fine accuracy.

Never say "never", never say "always" when it comes to castings.

[357maximum]

Never say "never", never say "always" when it comes to castings.




:drinks: :mrgreen: :drinks: I wish somebody would print that in "THE BOOK"

[scrapcan]

I have limited experience with glocks, but my model 19 (9mm) has not had a problem with leading. I have shot about 4 different bullets cast of everything down to range scrap and up to monotype. The barrel slugs at 356. I have shot cast sized to 355, 356, 357, 358. I was using lbt blue soft,javelina lube, Whitelabel lubes, and lee alox. I had light leading after 200 rounds at 355. None with any of the other sizes. I have began to use a saeco TC 124 grain style sized at 358 and have had good luck, it also shoots nicely out of a couple of 38 revolters. The gun gets pretty dirty using lee alox, but no leading.

My testing of my model 19 will continue but I am not a sole glock shooter nor am I a glock armorer. I recommend that each shooter evaluate individually how they feel about taking responsibility for their actions. We reloaders have to realize that sometimes it becomes our responsibility since we are the ammunition manufacturers.

A couple of comments need to be made. I do not run on the top edge. I do check case length and trim if necessary. Watch your seating depth carefully with the 9mm and 40 S&W. It doesn't take much to ramp pressures up. I had this problem with lee alox plugging up the seater die and shoving the bullet farther into the case than desired.

And just so you know, I had a Springfield p9 (9mm standard length) barrel split while shooting reloads. It was on me due to the reloads. I was lucky enough to be taking a mechanics of material engineering course at the time and got to see a host of calculations related to potential induced stresses. Based on the material and the calculations for the barrel, it would be very difficult to reach the stresses required to cause the split with the powder I was using at the time. Passed those results on the the manufacturer and I was still at fault and I paid to replace and fit a new barrel due to the use of reloads. No skin off my nose, but just to show what response you will get from the manufacturers.

[BD]

I got the "no cast lead bullets in Glocks" speech from the local Glock certified armourer. I didn't continue the discussion as he owns the indoor range where I shoot these days and doesn't allow necked boolits in there anyway. He's a Jewish guy in his 80's and i can see where a long number tatooed on the inside of his wrist has been removed. I don't give him any grief. This is a widely held opinion even among experienced folks who just haven't yet come to see by the light of the silver stream.

I don't own any of those glocks as yet although they seem to shoot OK. There's a bunch of young guys out there shootin'em and beating the pants off of me in the IDPA matches.
BD

[9.3X62AL]

Luober--

I surely did not mean to hijack your thread or your questions. As moderators, we try to let threads run without too much steering, a lot can be learned by staying off the brakes and letting the posters turn the wheel. As long as your question gets answered to your satisfaction--all good. If not, jump back in!

[Lee W]

A fellow caster and shooter has a Glock with 40-50 K boolits through it in the last eight years.
He was also told cast and Glock don't mix.
He does not listen sometimes.

[USARO4]

I have to add my comments to this thread. I'm just relating my experience with Glock pistols. I once owned a Glock 19 about 15 years ago. I was new to reloading then and had never been told that it was unsafe to fire lead bullets through a Glock. So I proceeded to fire several thousand rounds of lead in the gun. Some of these rounds were quite hot, I was new to reloading and thought max velocity was what it was all about. I loved the firepower from this pistol and would rip through magazine after magazine as quick as I could pull the trigger. The pistol took a real beating but was cleaned and lubed with care. I never had a problem with the pistol and ended up selling it to a policeman. End of that story. In April of this year my best friend bought a Glock 30 as his carry gun. He took it and a 1911 to the range to fire his handloads. His 1911 fired 3 mags of these loads without a problem. He did tell me the loads seemed quite hot. On the 4th round of the first mag in the Glock it exploded in his hand. His hand was numb and bruised, the pistol was ruined. He called me that night to ask what I thought might of happened. The first thing I did was check his load against several manuals. It was a Bullseye load right at max but not over. However the bullets were seated a little deeper than recommended. I think pressure destroyed his gun, but they didnt hurt the 1911. End of that story. My opinion? Simple, polymer pistols are not as strong as steel pistols and despite my own experience with a Glock I dont trust them.

[9.3X62AL]

9mm's are NOT a beginner caliber for the handloader.

+1 to the idea that 1911A1's are STOUT. Some years back, one of the DOJ criminalists did some experimentations in conjuction with the FBI lab concerning 1911 platform strength. This involved massive overloads of 45 ACP's set for destruction, and the things held together through repeated double-charges of Bullseye behind 230 FMJs.

Back to carting boxes onto the truck.

[MakeMineA10mm]

I'll chime in on this.

First, some background - I'm well over 30, and own many pistols other than Glocks, though Glocks out-number all the others now. I'm a Glock-certified Armorer (or, more accurately, I was one - the certification expired, and I'm heading back for another armorer's course this August). I also own a Ballisti-Cast and Magma Sizer and ran my own bullet business for a couple years. I'm a moderator over at GlockTalk, and have been a reloader since I was in junior high school.

That said, let me give you the short answer: I don't think anyone knows enough and has done enough scientific testing to assuredly say one way or the other that lead will or will not work in polygonally-rifled firearms. (Or, more to the point, I believe no one has established what the safe vs. the dangerous circumstances are, because I know there's safe ones, and I believe there are dangerous ones as well.)

Another moderator at GlockTalk is a Failure Analysis Engineer, who has examined, tested, and certified failed Glocks (and other polygonal-rifled weapons) that he established were destroyed by lead bullets. He ran a test with a Glock wherein he carefully loaded and measured the velocity and pressure of a series of (IIRC) 50 or 100 rounds with lead bullets. For a short while (20 rds or so), there were no problems, but then he started getting progressively-increasing velocities and pressure measurements, until, by the end, he was well over max pressure, with a middle-range load. (FYI - He repeated the test with jacketed and plated, and found that thinly-plated would also do the same thing, but slower. He recommended a couple brands of plated that he found to be the thickest, which did not have increasing pressure issues.)

In addition to this fellow, there have been anecdotal reports over at GlockTalk, and there is always Dean Speirs' website. (He's the guy who documented and coined the term, "ka-BOOM".

I, on the other hand, have had similar experiences to Al. My first Glock, I abused on purpose. (I didn't like or trust Glocks, and was able to get a well-used one cheap that I could abusively-test myself.) I fired 5600+ lead bullet HOT reloads (European pressure standards at that time were around 37,000psi) without any cleaning. It showed no problems and no pressure signs. (This is in addition to throwing it down-range against railroad tie backstops, burying it in ice, burying it in mud, etc., etc...)

I think a lot of pressure-excursions (fancy word for ka-BOOMs) have to do with bullet set-back. Lead bullets are a little more susceptible to this in auto-pistol rounds, especially when one takes into account variations of crimp due to variable case length. (Who trims 9mm or 45??? - Not me!)

I think the bottom line is there's no way to know. The METRIC caliber Glocks are the strongest and least likely to have problems. I also BELIEVE the 45 Glocks are pretty safe with lead, but that is just an instinct, and I have only the argument that the octogon rifling is less-intrusive against the bullet than hexagon-style.

There are too many variables and too much hear-say about lead in polygonal bores. Some will claim that my friend the failure analysis engineer, has a vested interest in claiming lead is bad in polygonal bores. Some will say that the muzzle-loading rifle with polygonal rifling is too different of an animal to draw correct conclusions. Again, there is just too much hear-say and variables.

I wish someone would categorically study this and figure it out. Until that happens, my recommendation is to watch your cases for pressure signs and clean your polygonally-rifled barrels every 100 rounds when shooting lead bullets. Also, check your loaded rounds against bullet set-back on the edge of your bench (yes, each and every round...).

[The Double D]

. However the bullets were seated a little deeper than recommended. I think pressure destroyed his gun, but they didnt hurt the 1911. End of that story. My opinion? Simple, polymer pistols are not as strong as steel pistols and despite my own experience with a Glock I dont trust them.

Are you old enough to remember SuperVels'? Well cringe, back in the olden days they were were blowing 1911's to smithereens. The cause, nickle cases and JHP bullets. No friction between case and bullet. As bullets were being feed in to chambers the nose of the bullet was bumped and the bullet was pushed back in the case. That reduced powder chamber area in the case and increased pressures enough to blow out through the bottom in the area of relieved feed ramps. SuperVel blamed it to oversize chambers and excessive cut back of feed ramps...sound familiar. Later SuperVel went to a heavier taper crimp and the problems disappeared.

About 15 years back our agency had a series of Glock kabooms with Federal Hydro shoks. Made me think of the SuperVel. I measured OAL of each cartridge in a box of ammo. Then I hand cycled all 50 rounds through my Glock. Not a one retained it's orginal OAL. I did a second test. I loaded magazines with ammo from another box I had first measured. I chambered and fired a round, then ejected and measured the following round that had loaded during cycling. The push back of the bullets was substantial enough to be noticed with out measuring and was far greater than the hand cycled rounds.

One magazine full we used a magic marker to blacken every bullet. We examined the cycle loaded bullet and every one of them had a mark on the nose of the bullet where the jacket rolled into the HP. We expected a mark on the side where the bullet rode up the ramp, but not on the nose with direct linear force towards the rear of the cartridge. That force could do nothing but drive the bullet in the case. Te resulting reduced powder chamber for the load just drove pressures up.

Again we have a nickel case, jacketed bullet with a particularly long flat nose and a steep feed ramp....kaboom!

The Federal Hydro shock ammo is the only ammo I have ever fired in my Glock 19 in 17 years that bulged cases.

As a result of my experience in this area I do not like loads that leave a lot of airspace in the case. I never use Bullseye for just this reason. I also apply a heavy taper crimp to ammo for Semi auto pistol. And, I have fired a bunch of lead through my Glocks without problems.

Dean Speirs' website. I shared this information with Speir. He scoffed at it. His response came back as more that he has an axe to grind with Glock than being interested in finding out what's going on. Sad, very sad and it serves none us of well.

[MakeMineA10mm]

Double D,
You and I are on the same page. I prevent bullet set-back by making sure my sizer die is a tiny bit over-aggressive, and my bell-mouth die is NOT over-aggressive. This results in a tight case-to-bullet fit that leaves loaded rounds looking like the old-fashioned bottles of Coca-cola. This bulge is a simple and quick way of preventing bullet set-back, much like factory-applied canelures, but without the extra step. (I have a Corbin cannelure tool, but it's too much of an extra step in terms of time and effort, compared to the slight bulge from tight resizing dies.)

I feel that bullet set-back is a HUGE issue / cause of catastrophic failures, and it goes very undiagnosed, because the evidence is gone when the gun explodes (the bullet usually is out the bore. Same factoid is true about over-loads. To my non-engineer but experienced eye, I would say once you've eliminated bore obstructions, I would look HARD at load being used and loading techniques of the reloader. If those check out, the test you described to test for bullet set-back is in order.

[scrapcan]

This is one of the most informational discussion on this topic I have read. I own a 19 and read a lot before I plunked down the money. I would like to see more data on the bullet setback. I think you guys are onto something there. I do recall reading some old info on the supervels and what was written above jives with what I remember.

My 19 seems to like 357 or 358 diameter cast. Of course they look like the proverbial coke bottle mentioned above (of course I like women with curves also). Never thought about bullet movement at feed as a possible cause.

Well now you guys have done it, you made me think on a Friday afternoon.

[9.3X62AL]

MM-10......

I suspect your "telescoping bullet" scenario is a BIG factor in the Glock kB equation. I think the kB occurrence is a "pertfect storm" scenario, in which the telescoped bullet--unsupported chamber area in older-series Glock 40's--and a weakened case area from past firings and sizings overlays the unsupported chamber area at time of firing. Murphy's Law gets no plea bargains.

I ran this scenario past a Glock tech rep that was visiting my agency a few years ago. He would not confirm my speculation as the cause of these events, but called my supposition "very sound" or something like that--then chanted the mantra. My opinion--lead boolits in and of themselves are NOT the cause of Glock self-disassembly, and can be fired successfully and accurately. Like you recommend, I take a luck at the bore every 50-100 rounds, and to date the results parallel what happens in other pistol and revolver barrels. Fit is EVERYTHING.

[largecaliberman]

Do all Glock handguns have a polygon type bore,and is the rumor that they do not handle (accuracy) cast bullets as well as a conventionally rifled barrel true? What semi-auto handguns seem to have the most "out of the box" accuracy in 9mm and 40S&W? Thanks

I have a 9mm Glock 34 and have been shooting cast boolits. I use a 124 grain TC Lee mold and lube it with Jakes ceresin. I find that this boolit "carries" more lube than some 9mm's in the market. The only difference is this lube will smoke a lot. I make it a practice to check for leading every 100 rounds or after shooting up 10 magazines. Before I load the next 10 magazines, I would run a dry bore brush a couple of times then run a dry patch to check for lead slivers/particles. So far, not even very very minor leading, just black soot from the powder and lube. :castmine: :Fire:

[The Double D]

I got this email today from Dean Speir. I don't think he will mind me sharing it with since he posted it on his website! The first part is his respones to the second part--my email I sent him...in 2004, I guess it can't be be said he doesn't respond.



----- Original Message -----
From: Dean Speir
To: ddgofer
Sent: Thursday, July 12, 2007 4:31 PM
Subject: Re: Glock blow outs


Don't know how, or why, this was lost in my Inbox for over three years, Douglas, but as my ex-wife used to note with considerable rue, I never throw anything out... and in this instance, that's a good thing. My apologies for this (extremely) tardy response.

But in trying to clean it out now I found your most interesting E-mail... I've added it as a "footnote" to http://www.thegunzone.com/glock/setback.html. You seem to have anticipated this situation by several years, and I love your testing protocol, and to answer your question, no, I know of no one who has performed such a test in a lab environment.

Someone has, however, performed measurements of the precipitously increased pressures in .40 S&W cartridges exhibiting projectile set-back, as my colleague Walt Rauch reported almost a decade ago. (http://www.thegunzone.com/glock/kb-notes.html#a3)

You don't happen to still have that spread sheet and any digital/digitized photos of those rounds, do you? I'd break that out as a separate page if you do, with as much, or as little, attribution as you prefer... I'm very sensitive the "political realities" of agency employment.

Imagine that, though! "Set-back" with those old 190-grain SuperVel rounds!

Of course, nothing's ever really new, is it? We just keep rediscovering existing truths, #1, and, #2, projectile design and the geometry of 1911-pattern feed ramps have made significant advancements since those days. I'll have to dig out my old boxes of SuperVel for a photo of those particular bullet ogives.

As always....

• Dean Speir <DeanSpeir@ >
«-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-»
Formerly Famous Gunwriter / The Gun Zone Maintainer

http://www.thegunzone.com

--------------------------------------------------------------------------------

----- Original Message -----
From: "ddgofer" <ddgofer@ >
To: <DeanSpeir@ >
Sent: Friday, 19 March 2004 18:59
Subject: Glock blow outs


I have looked over your webpage several time with great interest.

Each time I looked I wondered the same thing.

Back in the late 60's early 70's there were a rash of these type of blowouts with 45 ACP Super-Vel ammunition, in custom 1911's. We had one at a shooting match that scared the heck out everybody.

At first the Gunsmith's were blamed for over polishing the feed ramps, under cutting the case. This was hard to refute as it wasn't occurring in factory guns and it was obvious the case had blown out down the feed ramp.

. Later it was determined that there was an unseen problem that exacerbated the undercut feed ramp. When the slide cycled the nose of the truncated cone hollowpoint bullet would ram the feed ramp with enough force to set the bullet back in the case reducing the powder chamber. The reducing of the power chamber resulted in much higher chamber pressure for the given load powder.

Several years ago(10 or 11 years) my Agency took Federal hydro shok ammo out of the field for just this sort of problem in our 9 mm S&W and Glock autos. They were blowing out the bottom over the feed ramp. They didn't know what was going on.

I got two factory fresh boxes of ammo. With a magic marker I marked all 100 rounds and measured their overall lengths. Then I loaded one box into magazines and hand cycled them through the gun and caught them on the bed. I measured each round after it had been hand cycled, and every single round was shorter. The second box I load into magazines and fired. I fired one round letting the normal cycle occur, loading a round in chamber. Instead of firing the chambered round, I extracted and ejected it on a shooting matt. When I had fire up 25 rounds I took the 25 round left over that had been chambered by the firing cycle and measured them. They were all shorter also, drastically shorter than the hand cycled rounds.. I made up a spread sheet and turned it and the unfired test rounds into the Range Officers and it went away to the great black hole.

Has there been any work done in this area in regards to these blow outs?

[EMC45]

Funny thing about Micro- Groove barrels not being good for lead is that all the .22 rifles I have had by Marlin have Micro- Groove. I don't get it. I have been guilty of perpetuating the Glock barrel thing as well. Sorry. I don't own one and never have. I probably won't own one either.

[OBXPilgrim]

I bought a Glock 17 9mm around 1981, it was the first centerfire handgun I ever owned, even though I'd owned rifles & reloaded for them 5-7 years prior. I figured the only way I get used to it was to reload for it & I put close to 900 rounds through it the first 6 months I had it. Most of those were lead bullets. I found that I liked the 147 gr loads best & I got pretty good with that G17. I started shooting in local indoor IPSC matches with it (and a few outdoor as well), and ran close with alot of the race gun boys for quite a while. The best I ever ended up was 2nd place for the open class over our 6-8 week 'league'. Not too long after moving up in the racks I was told the lead loads were very dangerous & I shouldn't use them any more. I stopped using them, but never had a problem with them.

The loads I used were never 'barn-burners', but were not squibs either.

After shooting up all the lead I had loaded, I haven't used them since until about a month ago. Just got a 147 gr mold from Bullshop to start again.

[robert william]

I have put thousands of lead loads through my Glock 34. In the begining I would shoot a few and check the barrel. Now I just shoot till I get my fill and when I get home I clean the barrel (I haven't found any large amount of metal fouling to date). My loads are mild, 3.8 gr of bullseye under a 125 gr lead bullets with a heavy coat of Lee Liquid Alox.