My take on Glock's

[Failure2Stop]

again, I am not a science guy...

Neither am I, but I can't see how casehead diameter will increase or decrease slide velocity, especially given the way the weapons in question operate.

The Glock's barrel locks to the slide, essentially making the barrel and slide a single unit when the gun is fired. The barrel unlocks after firing, and the ccyle of operation continues.

Now here is where things get a bit dicey to me, as I wouldn't know how to do the calculations anyway. But here is what I see:

The rearward force of the fired cartridge against the breech block will be the same between identical cartridges with the only variable being case-head size. The recoil (rearward force) caused by pressure increase and bullet inertia will be the same, regardless of case head, right?

The force per area of the recoil may change by expanding or decreasing casehead diameter, but the total rearward force cannot change.

The total force applied to the breech-block will be the factor that affects rearward velocity (since the mass of the slide is the same).

I am basing this on the simple calculation of Kinetic Energy being: Velocity=KE/(1/2*Mass), since the rearward velocity of the slide is our concern. The force used in these calculations is in Joules, not energy per area. Thus, the overall mass of the slide and total rearward energy will be the determing factors in rearward velocity.

[rb40]

Hello, I'm new to this group, thanks for having me. I would like to know what everyones opinion is on the Glock 30. I just bought one and had the Tru glow night sights installed. I want to have a trigger job done and replace the barrel.
Thanks for any other advice. Rusty

[ToddG]

that should tell the tale - if you have never watched it you can't believe the things that many modern small arms do during firing - after you see some of it you'll be amazed some guns even work at all

My two favorites were the Beretta Cougar 8357 (the extracted case actually spins 180-degrees before leaving the ejection port backwards) and the original stamped-slide SIG P220 (the round feeds into the chamber not with the stripper rail, but because the slide's recoil force is enough to make the top round in the mag actually jump forward into the chamber).

My department switched to Glocks after five years of running the county police academy's firearms program. In my personal observation (and collective observations of all of our instructors), no other pistol came close to the reliability of the Glocks. I've personally seen myself and my students fire 10,000's of rounds through Glocks of all models.

Have you seen 10,000's of rounds fired through other brands? If so, what, if any, statistical data recording have you done?

A friend of mine who is a US Deputy Marshal informed me that the US Marshal's Service runs the firearms program at FLETC where all Federal LEO's go for their initial training. Their experience with all sorts of different pistols contributed to their choosing the Glock.

USMS does not run the firearms training program at FLETC. While individual agencies may have their own people, the overall program is run by FLETC staff, part of the Dept of Homeland Security. USMS is DOJ.

Another officer in my department spent a year as a firearms instructor training Iraqi policemen. He personally had a G19 at the range that fired over 100,000 rounds. He was convinced of Glock's reliability.

I don't believe anyone is questioning or challenging the reliability of 9mm Glocks in this thread.

[Federale]

From the reports I've seen even the higher velocity 155 and 165 grain loads haven't helped much.

As a member of a very large federal agency that uses the 165 gr. loads, I haven't seen or heard of any issues with our issued Glock 22s. And we issue a lot of them.

[markm]

As a member of a very large federal agency that uses the 165 gr. loads, I haven't seen or heard of any issues with our issued Glock 22s. And we issue a lot of them.

The G22 is a commonly found in many agencies out here, and I haven't heard anything other than the tac light issue from the instructors I know.

[Wayne Dobbs]

This has been an energetic thread!

It always amazes me how fast we can jump on a topic especially when somebody of Larry's reputation and stature begins it. Without a doubt, he's seen a few rounds downrange from quite a few platforms, so when he states something I STFU and listen, take notes and critically compare his input to my fairly decent level of experience (although NOTHING close to that of LAV).

I've yet to encounter a conflict with what Larry has to say if I remain objective.

Glock 9mm service pistols are great service guns in my experience. They are not perfect, but they are a standard of performance. In my first Glock armorer school way back in 1989 the trainer was a straight talker and he stated that the gun was designed from a clean sheet of paper as a weapon intended "to shoot bad guys in a hurry". I think they were successful in that goal, despite some grumbling about ergonomics, grip angles, etc. Cops and other pistol shooters can find something to bitch about with whatever comes along and what I've found most of the time is the more the bitching, the less competent the shooter with whatever they have!

I've watched literally hundreds of Glock 9mm guns in use, both here and OCONUS in training ops. I ordered 9mm and AK ammo by the 500 thousand round lot overseas and then watched it go downrange from students, my trainers and myself. I've watched and fired hundreds of thousands of rounds through 9mm, .40 and .45 Glocks here during my LE training career.

I found out the same things over and over: the G17 and G19 platforms were great, with an advantage to the G17 in overall dependability. I have one 2nd Gen G17 with 65,000 rounds through it with THREE total malfs and those involved reloaded ammo. It's never failed me with factory ammo. While overseas, I saw only one frequent problem with the G19s I encountered and that was the thin slide lock springs that were very prone to breakage. I saw many guns that would horrify most of us cleanliness and lubrication/maintenance wise that ran like a top.

The .40 caliber guns were pretty good, but not as reliable, function wise, as the 9mm guns and they were definitely hard on small parts and locking blocks (of which I've seen about a dozen broken ones). The 3rd Gen .40s are very problematic with attached weapons lights and while there are lots of "fixes" out there, the fact that a "fix" was required with a platform that's been around so long, using OEM springs, factory ammo and popular lights really bothers me. I think that those fixes are likely time bombs and therefore don't own anymore .40s and I strongly recommend folks against them. Unfortunately for Glock and all the end users out there, the G22 is the most popular model for the US market and most folks want a light on their gun. That is a recipe for disaster and I guarantee you that mess is coming at us in US LE circles, because most folks and LE agencies are not going to test their gun/light/ammo combination to see if it really works.

Bottom line is, like we all know, is that Larry is right. Get a G17 or G19 for your Glock pistol and consider the rest of them suspect at some level for really serious use.

[Federale]

The G22 is a commonly found in many agencies out here, and I haven't heard anything other than the tac light issue from the instructors I know.

I have heard of some other departments who have had issues with them, but Glock 22s are in a lot of LEO's holsters and if they were as problematic as some would make them sound, this wouldn't be. There may be some issues that arise with certain ammunition combinations and the Glock 22, but my agency has been using 165 Gr. bullets by the milllions and Glock 22s by the thousands and we simply haven't seen the data to support the assertion that the Glock 22 is a poorly functioning weapon.

[Wayne Dobbs]

I have heard of some other departments who have had issues with them, but Glock 22s are in a lot of LEO's holsters and if they were as problematic as some would make them sound, this wouldn't be. There may be some issues that arise with certain ammunition combinations and the Glock 22, but my agency has been using 165 Gr. bullets by the milllions and Glock 22s by the thousands and we simply haven't seen the data to support the assertion that the Glock 22 is a poorly functioning weapon.

They do work well until you make it a 3rd Generation G22 and add a rail mounted weapon light. Then your incidence of malfunctioning weapons will spike dramatically.

[Federale]

They do work well until you make it a 3rd Generation G22 and add a rail mounted weapon light. Then your incidence of malfunctioning weapons will spike dramatically.

See, you say "will" and that hasn't been our experience.

[TheDutchman]

Jmart it's my understanding the G22 is the #1 selling LEO pistol in the US.