Glock 20 w/ extended barrel vs. Glock 40 (MOS)

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As a back up weapon in the backcountry - any added benefit of a Glock 40 MOS over a Glock 20 MOS with extended KRG barrel of comparable length?

Would having the slide match the barrel length in the 40 be beneficial in some way over the 20 with an extended barrel? Plan to get an aftermarket barrel anyway, so trying to think of any reason why the 40 would be a good choice over 20. Whichever I go with I'm planning on a Trijicon RMR.
 

Rokwiia

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I looked at and handled both the 40 MOS and 20. I knew I wanted the longer barrel and was going to buy a KKM 6" barrel in either case.

When I was choosing, the 40 MOS already had the carve out done to accommodate a red dot. I also liked the feel of a longer slide which I believe helps slightly to tamp down recoil. Finally, I wasn't crazy about the look of the KKM barrel protruding outside the slide of the 20. Others may like that look and prefer the slight weight savings of the 20.

All things considered, I am pleased I got the 40 MOS and would choose it again were I looking for a 10mm. The KKM barrel is sweet and the combination of it and the 40 long slide make it the most accurate handgun I shoot.

Best luck whichever one one you choose.
 

Mt Al

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Just a different perspective, not claiming what I did is the answer. I carry mine for a sleeping pill if spending the night out and/or for protection during archery season in grizz country. Understood the likelihood of anything happening is low, but just helps me feel better about being out.

Either unlikely scenario is going to be close range and I'll be filling my Sitka boxers while shooting. My main goals are reliability, packability and energy in about that order. As such, I picked a Glock 20 and left it bone stock.

If I was more inclined to hunt with my pistol, I'd do the 40 hands down.
 
OP
Virginia Woodsman
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I looked at and handled both the 40 MOS and 20. I knew I wanted the longer barrel and was going to buy a KKM 6" barrel in either case.

When I was choosing, the 40 MOS already had the carve out done to accommodate a red dot. I also liked the feel of a longer slide which I believe helps slightly to tamp down recoil. Finally, I wasn't crazy about the look of the KKM barrel protruding outside the slide of the 20. Others may like that look and prefer the slight weight savings of the 20.

All things considered, I am pleased I got the 40 MOS and would choose it again were I looking for a 10mm. The KKM barrel is sweet and the combination of it and the 40 long slide make it the most accurate handgun I shoot.

Best luck whichever one one you choose.
Thanks. What holster do you use?
 

Beendare

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FWIW, My stock G20 shoots better than I can shoot it.

So much has been written on modding a self defense weapon...and why its a bad idea.

I suppose if you tune it, and function check you will be fine....but I've seen some horror stories of guys modding their firearms.....

____
 

Trader56

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They will both be great the 40 is more for waking up cranky and the 20 is more like a sleep aid.
 

Brendan

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Personally: Backup and protection weapon I'd personally choose the G20 with Night Sights. For hunting, I'd choose the G40 with a red dot.
 

mcseal2

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I got the Glock 20 with the 6" KKM barrel. I put Trijicon sights on it and like the combo. Mine had some issues with hardcast ammo at first with both the stock and aftermarket barrel that I have talked about previously, but it runs well now.
 
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I looked at and handled both the 40 MOS and 20. I knew I wanted the longer barrel and was going to buy a KKM 6" barrel in either case.

When I was choosing, the 40 MOS already had the carve out done to accommodate a red dot. I also liked the feel of a longer slide which I believe helps slightly to tamp down recoil. Finally, I wasn't crazy about the look of the KKM barrel protruding outside the slide of the 20. Others may like that look and prefer the slight weight savings of the 20.

All things considered, I am pleased I got the 40 MOS and would choose it again were I looking for a 10mm. The KKM barrel is sweet and the combination of it and the 40 long slide make it the most accurate handgun I shoot.

Best luck whichever one one you choose.

Well he and I came to the same conclusion. I'm more accurate with the G40 than the 20. Mine has a KKM match barrel, Deltapoint Pro 2.5 optic with co-witnessed Hawkins suppressor night sights. Try not to drool.

 

jeffpg

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I have owned and hunted with both. I liked the 20 with it's 6" Lone Wolf barrel but there's no comparison to the accuracy I achieved with my MOS with the Vortex Venom sight installed. The 20 may have carried a little bit in bear country during elk hunts, but the improved accuracy of the MOS wins hands down in my opinion.

I pretty much have the MOS with me in the vehichle at least wherever I go. I feel pretty secure with it close at hand, and if I add a AR into the equation I'm definitely gtg. I have a second MOS 40 that is highly customized and camoed out that never leaves the house.
 
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Its six of one half dozen of the other. The 40 gives you a longer sight radius, with the 20 you can swap back the original barrel and have a compact. I use a 29 with a 4.75 kkm and that works great for me. The shorter grip makes the pistol pack less noticeably on my pack belt. But they all are very reliable and accurate in my experience.

Edit: just read your original post again and if you are planning on a MOS I'd probably just get the 40 - even though the sight radius length would be moot.
 
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@Where's Bruce: That's a sweet setup. I like the co-witnessing with the night sights.

Once an optic has failed you, you learn quick. Had an EOTech fail on me (no reticle) with four 300+lb razorbacks 110 yards away. That AR10 now has a Trijicon 1X8 Accupower with BUIS.
 

cobbc03

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I love my 20, but having to buy a new slide or having it milled compared to a MOS model sucks. I wouldn't think about getting a barrel that's that much longer than the slide. If you're set on a long barrel, go with the 40, biggest benefit to the 20 is the size and weight, but she is one sweet shooter.
 

TheGDog

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Hey how is the accuracy of the 29 with that 4.75 barrel on it? (Perhaps better question is, did you notice a significant enough increase in accuracy that you felt happy about doing the upgrade?

Do you have to also replace springs or anything to run that?

This has me intrigued because I like the 29's size/form-factor. And having that longer barrel would actually give it a longer barrel than my trusty my ol' Ruger Security Six 4" .357... while giving me 4 more rounds and dropping loaded weight from like 39oz down to the... let's see.. 32.63oz
 
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Throwing in my $0.02 as I have been noodling on buying a glock 10mm Since I had to return a loaner 20 to a “friend”.

FWIW someone who has pretty good glock intel told me it is unlikely that the 10mm will get the gen 5 treatment anytime soon, if at all. He did say he is hearing rumors about MOS versions of the gen 4 20 and 29.

weight difference between the 20 & 40 is 5-6 oz so limited difference there.

for the 20, a KKm barrel and others can be had with some ports that help tame muzzle flip. The redirected Flash / muzzle blast can be a distraction, especially at night or low light.

if you are set on an RMR then the 40 makes a lot of sense. I agree with the poster above about suppressor height sights. I shoot a little USPSA and see all manner of red dots taking a dive During matches and practice.
 

Turkeygetpwnd38

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Something to think about. If you are going to do the glock 20 with extended barrel in a hip or drop down holster, the barrel protrudes from the holster and is unprotected. When you are side hilling or climbing over deadfall and slip a bit, there is a good chance your barrel could end up with a plug of dirt/debris in it, so having a slide that matches the barrel is beneficial (for sight radius as well). It’s not as big of a deal if it‘s on a chest rig, but still a concern. I have a glock 20, 29, and used to have the 40. 40 would be good as a dedicated hunting pistol, but I wouldn’t want to carry it as primary woods sidearm. Weight isn’t the only concern, with the extra length it’s just a little more unwieldy.
Also, send it off to get milled for your particular optic. It’s 75-125 depending on where, about the difference in the price of standard vs MOS. There are several weak points in glock‘s MOS system and I don’t like how high the optic sits compared to direct mount/milled.
 

Rokwiia

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for the 20, a KKm barrel and others can be had with some ports that help tame muzzle flip. The redirected Flash / muzzle blast can be a distraction, especially at night or low light.

I don't find there is enough muzzle flip with my 40 to warrant a ported barrel. YMMV
 
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