New Glock 20....Have a few questions

S

Stats Shooter

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Gun is Glock 20 Gen 3, larger frame.

I have a 22lb Glockstore recoil spring and SS guide rod assembly on order for heavier loads. I will be handloading some hot stuff.

Question 1: Hardcast bullets in Glock barrels. I have read about some fouling issues but I wonder if those folks are using hard cast of at least Brinell hardness of #24 to #26. Also, if you clean it regularly, wouldn't that make it a no issue?

Question 2: Are after market barrel s like KKM worth it over the stock barrel? I mean, assuming you don't want to go to a 6" slide setup or threaded barrel, and intend on sticking with the 4.6" stock barrel length, any good reason?

Question 3: Better yet, besides money, any reason not too go to an after market barrel?
 
A Glock 20 Gen 3 is on the short list.

I want to buy a replacement bbl to shoot .40s out of for cheap, and carry the 10mm barrel.
 
Just powder coat your cast bullets and enjoy....The only reason I don't have my 20 is because I didn't reload at the time. I always keep an eye out for a 20sf, one of these days I'll own one again.
 
I've had my G20 since '94. Have loaded it with 180GDHP up to 1400fps+. No need for a different spring or steel guide rod.

Have loaded/shot thousands of hard-cast, though I'll alternate between a magazine of cast and magazine of JHP. Now, use plated for 90% of shooting

Have a Lone Wolf barrel - chambers are very tight - had to send it back to be reamed, as cast bullets wouldn't chamber. The barrel has been sitting in the cabinet, untouched, for 8 years.

"Any reason...Worth it..." Without some qualifying information, very tough to answer. You've already seemed to make some assumptions with respect to the spring and guide rod.
 
Just powder coat your cast bullets and enjoy....
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Definitely this.

Using my G40 MOS longslide, I developed a backwoods "Thwaaaper!" load using SNS's 220gn 10mm poly-coated FP hard cast slugs. No lead residue left in the factory barrel, clean up is quick, and the secondary benefit of the ploy-coating is that lead boolits feed 'slick' up the ramp, so I've had no jamming issues either.

Coated HC slugs through the factory 10mm barrel are definitely the way to go.

On the KKM barrels, among the various reviews you can find by 10mm Glock users, they seem to be the most popular supplier of aftermarket tubes with fully-supported chambers, although LWD's 'drop-in' barrels in both 10mm and 10mm-derivative cartridges (e.g., .40 S&W, .357Sig) are popular too.

FWIW, I've had great accuracy from a Bar-Sto 10mm barrel (with fully-supported chamber) that arrived over-sized, rather than "drop-in," and had to be hand-fitted to my G29. I got it for the purpose of shooting maxed-out handloads. My local 'smith did the work, but Bar-Sto also provides that service if you send them your slide. Bar-Sto tubes are, however, spendier than the other makes.
 
Any reason...Worth it..." Without some qualifying information, very tough to answer. You've already seemed to make some assumptions with respect to the spring and guide rod.
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The only assumption I'm making initially, that I will need to confirm, is that the stock 17 lb recoil spring and plastic guide rod would be suboptimal to a 22lb spring. I'm a hand loader and sometimes I juice up loads for various purposes, and sometimes I download. Just depends on what and why.

I can use coated bullets then, so problem solved there...no need for an after market barrel.
 
I can use coated bullets then, so problem solved there...no need for an after market barrel.
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Well, remember though, ... 10mm Glockers bought (and still buy) aftermarket 10mm tubes for two reasons: first, so they can shoot HC lead boolits - which has been more or less mooted by the advent of coated HC slugs - and second, so they would have a fully-supported chamber in which to detonate their near-nuclear handloads, or the super-hot 'Boutique' loads from UW, BB, or DT, without fear of the dreaded KABOOM!

That said, the chamber on my G40 MOS is actually pretty good. Some years ago I did buy a stock-length LWD 10mm barrel for my G20. Today I'd likely get it from KKM.
 
more or less mooted by the advent of coated HC slugs - and second, so they would have a fully-supported chamber in which to detonate their near-nuclear handloads or the hot 'Boutique' loads from UW, BB, or DT.
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You don't need a fully supported in 10mm, or 9mm or any other cartridge. All the examples of confirmed kabooms caused by unsupported brass failure I have seen are in the .40 s&w. Believe me, if I thought a $150 barrel was necessary for safety, I would get one. It is why in my .40's I use s$w m&40's just as insurance.

The biggest reasons for so many kabooms in the .40's are #1: The .40 is a relatively small case, so bullet setback of even .01" is enough to spike the pressure very high with 180 gr bullets, well over 40k psi or possibly 50k. Not as big a deal in the 9mm or 10 mm because small changes in seating depth do not matter as much pressurewise.

#2: For a while federal .40 cases were very thin causing factory ammo kabooms by Leo's who frequently chambered the same round. Setback and thin brass = kabooms. Federal corrected this a while back.

#3 Gamers using very fast powder and double charging, and gamers attempting to download slow powders which resulted in detonation...which would naturally exit in any unsupported area as a path of least resistance.


I have been loading .40 s&w for years. The manuals keep you around 29kpsi, I load to around 32k so over book max for defense and defense practice loads. They have fired fine in some of my family members unsupported glocks too.

I didn't want to go on any soap box on this thread, but internet warnings and myths abound regarding some firearms. And if they are repeated enough, they become "common knowlege" despite being false, or at least misrepresentations of the truth.

I will soon be making ammo commercially (side job) and a good friend of mine makes ammo as a full time job. All common chambers and cartridges have been tested. He has tried to see what it would take for a kaboom in glocks...like the internet legends promote and even double charges with powders like Hs6, or cfe pistol won't do it in glock chambers. The only conclusion after hundreds or thousands of tests is: a screwup dropping too muc hot powder, setback, or detonation of too little slow powder.

Not arguing with you agtman, just quickly addressing why I don't have any reservations about going full tilt in a standard glock 10mm chamber.
 
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StatShooter - no basis to believe the stock barrel, spring, rod are suboptimal. The only thing suboptimal is altering the stock pistol. The Glock 20 was designed for full power loadings. At the time of it's inception, PSI was greater than 37500psi. All I have to go on is my own G20. But, I've had no issues at all. My favorite Glock by far.

+1 for your last post regarding the "Kaboom" bulls**t. I've heard that so many times it's ridiculous.

FYI - if you are going to start making rounds commercially - get a good insurance policy and attorney. I wouldn't touch that business for anything. I give you credit. :-)
 
Not arguing with you agtman, just quickly addressing why I don't have any reservations about going full tilt in a standard glock 10mm chamber.
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Yeah I got that, and agree with what you said... but guys still buy 10mm aftermarket barrels for their Glocks out of an abundance of caution. I was hinting at sarcasm when I referenced "the dreaded KABOOM!" ;)

I've reloaded several thousands of 10mm rounds over the years, re-using brass through several firings, and have never had one. I'm careful about it though, and any 'iffy' cases get tossed. The 10mm is a very forgiving cartridge to reload for, and although I shoot different bullet-weights, none of my handloads run at the ".40-level." If I want play at that energy level, I'll pull out the aftermarket .40S&W tube for my G20 and drop it in (or similarly with my G29), and shoot up a few boxes of relatively inexpensive .40 factory ammo. Lately though, I've been hot-rodding my 10mm handloads through my G40, which is my smoothest and best shooting of the three Glocks.

You're right about there having been hundreds of documented cases of .40S&W KABOOMs! - and not just idiot reloads, but some happened with .40 factory ammo as well.

Good luck with the ammo side-job. :cool:
 
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I can tell you why I bought an aftermarket barrel (a few actually): the factory chamber is huge and the brass balloons up so that you have to run it through a bulge buster (or a Dillon re-sizing die) to get it back to spec.

I have three Lone Wolf Barrels (Two 10mm and a 40) and have well into the thousands of rounds through them and the spent brass is much nicer if you care about that. If I was woods carrying or dare I say carrying the G20 for self defense, then I put the factory barrel back in.

The factory tube is designed for maximum dependability, not keeping brass nice. So....

The only malfunction I have ever experienced with the LW barrels was with 200 grain WFNGC from Doubletap. (That I hand loaded in Starline Brass)

They would hang up on the feed ramp. Leaving skid marks even a few times. I haven't had the same issue with the same bullet in the 230g weight though. Must have a different enough profile to work.

I use the factory spring, even with hot loads. No problems except the one noted above. My G20 is a Gen 4.
 
I had a Glock 20, and a bunch of other 10s. I won't get into the factory vs. aftermarket barrel debate other than to say that I consider case head support to be a very good thing. Especially in higher pressure calibers, whether in a Glock or other manufacturer's pistol.

As to recoil springs, I'm not sure anyone needs to worry too much about having steel guide rods, extra powerful recoil springs,etc. in a Glock. A major factor in recoil operated pistols is slide weight. The Glocks have heavier slides than any other service sized 10MM pistol I'm aware of. Ounces heavier than a Colt Delta for instance. It matters. The recoil spring must reliably return the slide to battery. If it does that, it's working right. In any case, the Glock is about the last 10MM pistol that I'd worry over recoil springs, guide rods, etc.......ymmv
 
I can tell you why I bought an aftermarket barrel (a few actually): the factory chamber is huge and the brass balloons up so that you have to run it through a bulge buster (or a Dillon re-sizing die) to get it back to spec.
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I run all my 40 s&w brass through a Redding grx now. Mainly because I pick up range brass these days. My M&p doesn't need it done if that's what it was fired in. But gkicks do. So if my 10mm requires it, I'm already equipped.

A major factor in recoil operated pistols is slide weight. The Glocks have heavier slides than any other service sized 10MM pistol I'm aware of. Ounces heavier than a Colt Delta for instance. It matters. The recoil spring must reliably return the slide to battery
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I hadn't thought about the slide weight but it makes perfect sense. Like buffer weight on an AR. But I would think recoil spring would matter too. Some ammo makers and independent tests have verified lower velocity extreme spreads and higher mean velocities with 22 vs 17 lb springs in 10 mm....ES reductions from 64 to 17 fps on ammo near 1200 fps. And mean velocity increases of 40 fps with that same ammo. That seems worth it to me. But I'll do my own testing to confirm/refute.
 
So here's another question then. with a longer KKM barrel. Like the 6", do you need the bigger slide? Otherwise it would look kind of funny. Or, I guess I could get the threaded barrel and use the same slide.
But suppressing a 10mm seems silly because unless I use really heavy bullets, full power loads will be supersonic.

Also, what about double diamond barrels or storm lake?
 
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Stats Shooter said:
So here's another question then. with a longer KKM barrel. Like the 6", do you need the bigger slide? Otherwise it would look kind of funny. Or, I guess I could get the threaded barrel and use the same slide.
But suppressing a 10mm seems silly because unless I use really heavy bullets, full power loads will be supersonic.

Also, what about double diamond barrels or storm lake?
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Yeah you can use a longer bbl, no longer slide needed.

Silly is in the eye of the beholder. I think they look pretty cool.
 
Silly is in the eye of the beholder. I think they look pretty cool.
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Fair point.

I'm thinking now about getting an Alpha Wolf threaded barrel. They are made in USA, they add nearly 1" to the barrel OAL giving more velocity, and I can put on a compensator if I want or suppressor. And they say I can use hard cast with no worries which is my main concern. And the added 1" of barrel is a nice benefit.

A good 230 gr hard cast FN at 1200 fps is all business.
 
close one

I've seen in print where a heavier recoil spring in the G20 will supposedly aid in reducing premature unlock, which will rob velocity and I suspect beat your pistol up as well. Seems like the gist of the article was if one sees wide swings in velocity with heavy ammo ( the article may have been by Buffalo Bore) a heavier spring could help. That is all from recall.....I do not have a source.

Closest call I've had reloading was with a g20. A max load of Unique....and primer "X" had always been safe. I switched primers, all I had on hand, and primer "Y" boosted pressures high enough to really bulge some cases at the ramp. Change components.......reduce your loads. I was lucky.
 
A tribute to my new friend (Glock 20)

I have now had some time to put some rounds down range. I have fired about 350 rounds using some armscore target ammo and some heavy underwood 200 gr high velocity rounds.

I want to first say that this full sized glock 20 feels like it was built just for me. I have long fingers, not fat but long. The standard frame on the Glock 20 Gen 3 puts my finger in perfect position on the trigger and my thumbs seem to naturally lay right where they should. I have spent a lot of time and money on grips and triggers and in many cases still couldn't make them as comfortable as this Glock 20 is in my hands right out of the box.

Because of the grip, finger position, and longer sight radius of a large frame pistol, my groups were almost with my .44 mag 6" barrel at 30 yards....and I have been shooting the 44 for several years and have a good hand load for it. Even rapid fire (about a round per second) I was able to shoot volleyball sized groups at 30 yards, and Im not even a competitive pistol shooter!

The longer slide and heavy recoil spring makes this gun and my hands move up and down together as the slide moves back and forth creating a nice natural rythm for following up shot after shot.

The only modifications I am going to make, as I talked earlier, is a longer threaded barrel to shoot cast bullets, and I prefer 3 Dot sights so I will throw on some Trijicon night sights.

We all know the feeling when we get a new gun. We have some fun with it, shoot the heck out of it. But in some cases, the fun wanes a little and we move on to the next new gun while the old "new toy" sits and gets pulled out for maintenance or only occasionally when you want to shoot it. I have several of those (like my custom AK 47 I built or my Dan Wesson .357). But SOMETIMES, you get one and you know right away that this one gets its own storage position, near the front because you use it so often (Like my heavy varmint AR or my custom built bolt action target .22LR).

My only regret is that I didn't get one sooner.
 
Just curious. Did you consider a Glock 40? 10mm with 6 inch barrel and ready for optical sights.

Additional question: Have you thought about Glock factory night sights? They seem like a great value.

A Glock 10mm (model 20 or model 40) has had me interested for quite a while.
 
Just curious. Did you consider a Glock 40? 10mm with 6 inch barrel and ready for optical sights.

Additional question: Have you thought about Glock factory night sights? They seem like a great value.

A Glock 10mm (model 20 or model 40) has had me interested for quite a while.
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The Trijicon 3 dot night sights and glock factory night sights are similar. The ones I am putting on might actually be the same.

As for the 40 vs the 20, I held both of them. The 20 felt better to me. I have no desire to mount a red dot on it, and even if I did, there are mounts for the 20.

Its all personal preference with respect to the two guns as far as I can tell. The 20 factory barrel and slide is shorter, and as such you can put on a longer barrel and muzzle device where the 40 with 6" barrel and matching slide would require a 7" barrel and be very front end heavy.

Also, the 20 is a bit cheaper.

In the end, it seems to be a personal preference thing and what you intend to do with it.
 
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