[Bandit01]

At local shop, I've been warned not to shoot reload's, especially hot loaded 10mm in Glocks. I was told that Glocks aren't reliable and could cause a serious malfunction.

Assuming that this is correct, can someone give me a detailed explanation of why.

[waktasz]

Poor reloads and the not quite fully supported .40 barrel are a bad idea. Shooting lead is also bad because of the polygonal rifling Glocks use. Quality jacketed reloads should not be a problem.

[Bandit01]

Forgive my ignorance but here we go.

You say that the "not quite fully supported .40 barrel are a bad idea".
Is the .40 Glock barrel and the 10mm Glock barrel the exact same?
Is there an aftermarket 10mm barrel that'll work in the G20 that's strong enough to handle "hot loads"?
I had an accident with my old G20 due to bad reloading. I accidently shot a squib and then fired a full load afterwards.
On average, I'm putting around 200 rounds through my G20 a week and it's holding up well. Is this luck or will it eventually wear out?

[waktasz]

Shooting behind a squib will likely destroy any barrel. I'm not sure about the 10mm barrel being the same as the .40, but I think that it is, in fact, slightly different. The problem with the .40 is that hot-loaded ammo plus old brass can bulge the case on the part that is unsupported near the feed ramp. If you reuse the brass too much or overload a cartridge, there is less barrel around the brass holding the pressure in.

[Zak Smith]

Reloads are fine in a Glocks.

They are not the best platform for super-nuclear loads, but certainly +P loads are fine (when such a load is defined, e.g. 9mm).

Do not use unplated lead bullets. The lead fouls on the polygonal rifling, builds up, and can dramatically increase pressure to KaBOOM levels in as few as several hundred rounds.

Reloading does not suffer carelessness or foolishness.

-z

[Black Snowman]

Ditto with Zak, I have about 6000 reloads through my 40 S&W Glock. They have all been Jacketted (mostly Zero) or plated (mostly Rainier).

[model 649]

Take a look here, for what it's worth. Good explanation of case support by chamber. http://www.thegunzone.com/glock/gindex2.html
Josh

[Clark]

Measuring and testing Glock 40sw and 10mm barrrels, I have found the 10mm to be worse.
I think the reason we hear about 40sw more, that there are so many more of them.

Aftermarket barrels are the standard solution for hot loads in Glocks.

[redneck2]

I am the first to conceded that Clark has way more experience than most anyone else here, especially me

that said, from my limited experience and what I read, I suspect there's a big difference in "hot" 10mm Glock loads. From my experience, I think slower powders are a lot, and I mean a lot more forgiving

I've got a G20 and I've used 180 Gold Dots with pretty much all the Blue Dot powder they'll hold in Starline cases. No "Glock" bulge. None.

I'll give a qualified "I think" that you get into more trouble with faster powders than the slower ones. Well, actually slower powders are nearly always more forgiving than slower powders.

If you go on GlockTalk, Mike McNett's worked up a lot of hotter loads for the 10, and IIRC they all seem to use powders in the range of Blue Dot.

I don't care what you shoot if you plug that barrel. Even a .22LR will ring or burst the barrel.

The "Glocks blow up" gets a little old. Let me take your 1911, shoot a squib and then a full power round and see what happens. And yes, I've got a Delta Elite, a Springfield Loaded stainless, and a Colt 1911. Some guys tend to paint everything with a broad brush.

[Zak Smith]

As I said,
Reloading does not suffer carelessness or foolishness.
It's serious business and anybody who acts otherwise deserves what they get, and is doing everyone else a disservice by blaming their equipment.

[The Bushmaster]

I sure am GLAD that I don't own a glock. Of all of my 20 firearms, 9 of them are mix revolver and autos. I have no problem with any of them except a firestar M43 (worn extractor. I've shot it a lot). Oops...Forgot an apostriphy...

[Joe D]

Gosh, guess I had better stop shooting lead bullets in my Glock 34 and 35. So far this year I have put over 4,000 lead bullets through them.

Must be something wrong with the G34 barrel. It has about 1/10 the amount of lead in it that a 9mm conversion barrel for my G35 has after a session. Put 300 rounds through the G34 this week. Two passes with a Bore Snake and any trace of lead was gone.

Let's address the unsupported barrel myth. First of all there has been only one handgun with a fully supported chamber. The old Auto Mag with it's rotating bolt came as close to a "fully supported chamber" as you can get. I have fired tens of thousands of 170 PF reloads, using a 180 gr Rainier bullet, through my G35 without any problem. Glocks are no more likely to blow up than any other gun. A double/over charge will blow up any gun.

Most folks get in trouble with lead bullets by trying to drive them to insane velocities. My 9mm load is a 125 gr bullet at 1050 fps. The .40 load is a 180 at a little over 800 fps.

Let's clear up another myth. No gun manufacturer wants you to shoot reloads, not just Glock.

Redneck, I too have seen all of them blow up, HK, Sig, 1911 Beretta and the list goes on. The problem is, as my old Grand Dad once told me, 90% of the people in the world don't think. They just go through life reacting. There is nothing worse than an "Internet Parrot". They don't check things out for themselves. They just "parrot" something they read.

One more note on lead bullets and Glocks. I tend to belive very little of what I hear/read, especially on the internet forums, and about half of what I see. I decided to test my G34 with lead bullets just to see if all the lead bullet warnings I kept reading were true or false. The Glock barrel profile, in my mind, should have less, not more, leading issues. I fired 1,000 rounds of 125 gr Valiant 9mm lead bullets through it without cleaning the bore. I checked the bore every 100 rounds for lead build up. At the start and end of the test I checked 20 cases for pressure signs. Primers looked the same as was case expansion. At the 1,000 round mark there was a small ammount of lead present in the barrel. Much less than I get in my 1911s using lead bullets. Four or five passes with a Bore Snake and Hoppe's 9 removed all traces of lead.

Reloading is not an art. It is a science.

BTW you don't have to believe a word I say. You should check things out for yourself.

[rick_reno]

At our informal bullseye shoot earlier this week this subject came up – one of the cops present said they’d had some Glock problems with ammo from the Philippines. The brass was two piece, the cylinder part was attached to the headstamp part and when they separated the guns had big problems – which I think would be true of any handgun. He added that they stopped using that ammo and everything was fine.

[Zak Smith]

There has been some pressure data on the lead issue posted. I believe it was posted to GlockTalk c.a. 2000. It also depends on lead hardness.

[Joe D]

Zak, there really was not any documented info on Glock Talk. One of the moderators had stated that he had pressure readings to prove that lead bullets caused a dramatic increase in pressure due to lead build up caused by the Glock rifling. When I challenged him to provide me with his findings and list the equipment,ie transducer, test barrel etc., he used to gather this info with, he was unable to do so. I think the lead bullet myth started with him.
It never ceases to amaze me how quickly someone starts stuttering and backing up when you ask them to substantiate their claims.

[Master Blaster]

I have a a g-26 and a G-34, I have put about 2,000 hardcast lead bullets through the G-26 with no problems at all, lead build up was minor and easily removed with a brush. The G-34 has been shooting plated raniers and plated berry's, I havent been using the hardcast lead, because of the smoke. Plated bullets run cleaner and there is less lead vapor to breathe. The only gun I own that says do not shoot lead in the manual is my beretta 92 FS. I tried it in the beretta anyway and after about 20 rounds the bullets started hitting the target sideways leaving a perfect profile keyhole. I took the barrel out and there were shreds of lead hanging from the rifling, the worst leading I have ever seen in any handgun. DO NOT EVER SHOOT LEAD IN A BERRETTA 92. I think the reason is because the rifling seems to have a faster twist than any other 9 mm I own. 9 mm rifling in general was designed for jacketed bullets IMHO. The problems folks have with the Glock are due to double charges, over pressure reloads caused by setback due to insufficient crimping in the 40 S&W, and shooting into a stuck bullet. The unsupported case head is nonsense, Glocks are no less supported than a 1911 or pretty much any other semi auto handgun, If you dont believe this take the barrel out, drop a round in and compare for your self, I have.

[Zak Smith]

Here's the original thread I was remembering:
http://www.thefiringline.com/forums/showthread.php?s=&threadid=82

A summary of the data:
http://thefiringline.com/forums/showthread.php?p=642209

Is that the same guy?

A friend of mine also blew up his G23 shooting lead.

[Joe D]

Those are the threads. I never could get him to provide the info I asked for. Make and model of transducer, test barrel, recording device etc.
Forgot to mention the lead bullets I buy run in the 19-21 range.

[Rockstar]

Joe, what are the brands of tranducers, test barrels, recorders, etc., that you personally use for testing Glock barrels and can recommend??

[JohnKSa]

I think the lead bullet myth started with him.So you're saying he was good enough to convince Glock to start telling folks to avoid using non-jacketed ammo in their pistols--but not good enough to convince you.

[Joe D]

Rock, I guess I am missing your point. I never claimed to have any sophisticated test equipment, MarkCo did. I just wanted more info as some of his earlier posts left me wondering about the validity of his results. I never received any model info from him. It would have been pretty simple to provide this information if he had such equipment. How do you know if you can or cannot shoot lead bullets in Glocks? Do you even own one? Have you ever questioned why not or is that beyond your ability.

John, no I am not certain where it really started. I don't think Glock spells out that warning in their manual. I guess one day I should read the manual.
The test that I did was pretty simple, but effective. Primer flow and case head expansion are good indicators of pressure. Does it tell you what the pressure is? Of course not. Flattened primers and increased case head diameter does tell you the pressure is increasing. I did establish a baseline with my case diameter measurements. All the diameter tests were done with the same brand and lot of brass. The primers looked the same under a lighted magnifier.
As stated before find out for yourselves, or go through life like sheep and never question anything.
Well gotta go shoot an IDPA match. Hope my .40 Glock does not blow up with those dangerous reloads.

[Clark]

This is a piece of 30-30 brass, cut down to 10mm size, overloaded, and shot in a stock Glock 20 [10mm pistol]

Notice the long distance between the base of the case and where the case bulge forms.
That long distance is the result of Glock's choice on how deep to cut the feed ramp.

[Bronson7]

I also believe the cast bullet/Glock thing is a myth. I've asked for documented testing to support it and guess what? All you get is anecdotal bs about " I knew a guy who knew a guy". The people who've KB'd their Glocks while shooting lead seem to attribute the KB to lead. I guess they can't stand admitting their reloading process got away from them. Most folks who say lead in glocks cause KBs ( and I really believe this) are only parroting what they've heard or read. Now, if someone can present EVIDENCE that lead causes KBs, I'll listen. Just because someone happened to be shooting lead when their glock kb'd just aint going to convince me. If you shoot lead, clean your gun after each range session and you'll be ok (should be doing it no matter what your shooting)
Bronson7

[juggler]

I've been shooting nothing but my own reloads for several years now. My Glock 27 handles it just fine, but I DO make sure to perform quality control checks at least three times. AND I only use jacketed bullets.

The pressures in a .40 are such that I have never felt the need or inclination to go for hot loads. I usually run 4.7 grains of Bullseye and keep the OAL at 1.135.

[RON in PA]

Used to own and shoot Glocks with my reloads. Used plated bullets in 9mm and 45 ACP. Never had a problem in thousands of rounds.

As for the statements that Glock specifies no lead bullets; all the Glock manuals I've read specify no reloads (same as most manufacturers), nothing about lead.

[Joe D]

Got back from the match. It was a miracle that I managed to win it. It is hard to shoot fast holding the gun with one hand and turning your head the other direction to protect yourself from those reload kabooms. :)

[Rockstar]

Joe, I wasn't making a point, just trying to get information. I thought, perhaps, that you'd done similar testing and were familiar with better/worse brands of testing equipment, etc.

I don't reload lead, so the studies involving shooting lead through Glocks don't apply to me; was just curious.

I've followed published data by another individual on various boards who also doesn't use the type of equipment that you mentioned, but he publishes, as facts, chamber pressures,etc., supposedly from a software program that he's using. I'd prefer the method that you suggest, using test barrels, transducers, etc., if I were publishing research results for public consumption.

[Joe D]

Rock, I can't see how a software program can give you accurate pressure readings. I would be real skeptical of his results. As I recall pressure barrel chambers are cut to minimum SAAMI specs. The reason for this is a max pressure load in this chamber should be safe in the larger production chambers.
I have not checked into what the equipment would cost. I would think it would be prohibitive for the home user.

[Zak Smith]

I can't see how a software program can give you accurate pressure readings.
Internal ballistics is the study of the ignition and burning of powder and the acceleration of the bullet through the barrel. It follows physical laws and can be modeled by applying the best that we know about such physical processes.

The most common internal ballistics modeling program is QuickLoad. With the understanding that the experimental results will differ from the predicted results due to things like barrel dimensions, throat dimensions, primers, etc, QL does predict velocity and pressure pretty good on average. In some of my rifle loads, its calculated results for velocity are within 10 or 20 fps of the actual results.

-z

[Joe D]

I would be interested as to how accurate it really is. As I stated before most pressure barrels are cut to the min. chamber specs.
How can it predict the increased pressure due to lead buildup in the barrel? I don't think that is possible.
I also think there are way too many variables that come into play to accurately predict pressure. Some of which you named.

[Zak Smith]

You could adjust the land and groove diameter parameters to reflect a constricted bore.

[Joe D]

Zak, I would be interested in looking at this software. Where can I obtain it?
Still don't see how it can compensate for leading as it is not uniform in it's distribution.
On the other hand this old dog is certainly willing to explore new tricks. I for darn sure don't know it all.

[Zak Smith]

http://www.neconos.com/

[Clark]

That quickload software is right on the money for predicting velocity in 8mm or .223 bottleneck cartridges, but sometimes in straight wall, the powder blows out the muzzle and quickload is way off. It ever says that in the instructions.

For instance, it predicts the velocity right in the middle of a string over my chrono with .223, but sometimes thinks my 9mm overloads are over 1,000,000 psi. That is in 9mm loads that do not even pierce the primer.

It is also accurate on pressure, in that the load for the pressure point at which the primer pocket expands is accurately predicted in 8mm, 308, and .223.

[Rockstar]

Joe, like you, I wouldn't be nearly as concerned about the prediction of velocity as I would the prediction of chamber pressures. As you said, there are just too many variables for one to trust one's life to a software program for determining pressures.

I don't know what method the MarkCo that you mentioned uses, but I guess it's possible that he's actually taking measurements. I'm surprised that he didn't respond to your inquiry about the nature of his equipment.

My problem would be with folks posting load data for general consumption, advertising as a fact that "X" load produced "Y" chamber pressure, when, in fact, the guy doing the so-called testing doesn't have a clue what the real chamber pressures are, assuming that he's depending on a software program.

If the data is posted with a large warning that the pressures are only estimates and might not be accurate, then, I guess it's "user beware."

[Khornet]

Got my G22 in the early 90s. Have shot nothing but handloads after using up 2 boxes of factory.

Bought 1000 180 gr hardcast and began loading up. Didn't load hot; I almost never do. 50 rds produced marked leading which wasa real chore to remove. Not knowing about this Glock barrel thing, I tried again and got the same result. A week later (about 1995 or so) I saw a clipping from a magazine at my club about the Glock lead problem. I still have 900 bullets left. Never used lead again.

I've shot thousands of plated bullets with no problem.

Not saying those who shoot lead with no problem are liars, just saying I had heavy leading. Clearly there are multiple factors, principally hardness and velocity, and maybe the individual barrel.