10mm questions

[SDBlaster]

I'm going hunting this year and want to take a 10mm as a bear gun. I'm looking for a 10mm Glock 20 but someone told me I can convert my Glock 21 into a 10mm ??? Is that true ? And if so is it a barrel conversion or entire new slide set up ? Or am I just better to buy/ ppt a 10mm Glock ??? Thank you !

[Munny$hot]

I went this route before so I'll save you the headache, waste of time, and money. I bought the Glock Store conversion barrel which sounds like the easy, but it's not. The problem is the breach face for the .45ACP is larger then the 10MM case head so it will not extract reliably since the live/fired case is not held by the extractor/breach face cutout even when using a 10MM extractor and G20 mags. Converting your Glock 21 to fire 10MM is very simply done by either buying a complete factory or Lone Wolf G20 slide/barrel assy. You may have seen the horror stories of the unsupported chamber creating catastrophic failures or bulging cases which did happen with early model 10/40MM, but Glock has solved that problem and shooting Buffalo Bore hard cast is not a problem. The only thing I would say is if you plan on running anything above 200 grain bullets I would buy an aftermarket barrel. Under 200 grain a stock barrel will do just fine. While I keep my GP 10mm under 1250 FPS it's has plenty of giddy up. It's like having a semi auto .357 magnum that hold 2-3X more than 5 shot revolver.

[Reno-Kid]

Get a Marlin 1894 Trapper 10mm

[hermosabeach]

no bids yet-
$200 or $250 buy it now for a Glock 20 complete upper - BUT - its for a Gen 4

https://www.gunbroker.com/item/1170578361

If possible, get a used OEM complete slide and upper



I recall Gen 3 glocks used the same frame for the 20 and 21. Slide is different based upon the case head

for your scenario - you need reliability and nothing finnicky...

Create a GB account and save a search to be notified when an item is posted...

[Nego]

do yourself a favor buy a ruger super alaskan in .44 :<)..


rugerpix.jpg

[Spyder]

You can find 10mm barrels that have a wider breech face to fill the G21 slide. Mine shoots extraordinary well out of my G21 with a 6" stainless barrel. Very fun.

A regular 10mm barrel will fit and work as well, but the breech gaps on each side make some people uncomfortable. And it's ugly. I shot hundreds of mine with the mismatched breech. I think mine is a Barsto

[Nego]

You can find 10mm barrels that have a wider breech face to fill the G21 slide. Mine shoots extraordinary well out of my G21 with a 6" stainless barrel. Very fun.

A regular 10mm barrel will fit and work as well, but the breech gaps on each side make some people uncomfortable. And it's ugly. I shot hundreds of mine with the mismatched breech. I think mine is a Barsto

i run a bar sto .357 sig in my XD tactical fine barrel

[Spyder]

https://www.aztecharmory.com/index.php?route=product/product&product_id=40665

[Spyder]

Even better and in stock

https://www.glockstore.com/GS-Gen4-.45ACP-to-10mm-Caliber-Conversion-Kit?quantity=1&custcol9=81

[ar15robert]

Hear you can get a barrel for the 21 to go to 10mm but can’t convert the 10 mm to 45 with barrel change.

best way is complete slide IMO.

[walmart_ar15]

One thing people forget about a bear pistol is that the gun may have to be used when the bear is already on top of u and u need to fire off while pressing the gun against the bear’s body. It is bad news for autos as the slide can be out of battery. Revolvers r more suited in that situation. 500 S&W has a specific bear model.

one may get more mileage with a bear spray.

conversion barrel will never be 100% reliable due to breech face dimension. FTF or FTE r both possible issues. But probably > 95% from most folks experience.

[acaligunner]

All I have to deal with are 2 legged animals.
A lot of folks from AK trust the Glock 20 ( 10mm ) and it has a good record ( according to what I’ve read no experience with that ).

If we go by a grizzly or larger already on top of ya, I think hardly anything is good at that point, because you’d be pretty jacked up by the bear.

There’s also YouTube video of an automatic Simulated bear cut out and the difference between who could get off shots / hits on the attacking moving bear - and the auto did better times and hits than the revolver.

I think the advantage ( or disadvantage ) in such a case is to get off fast shots on the moving, grunting, out of control bear ( I don’t know if that means ) spray and pray ( within reason ) as much lead to the bear.

10mm yeah it’s not as powerful as the 41mag, 44mag, 454casul, 460, 480ruger, or the 500mag - but the G20 in 10mm is lighter, easier on the recoil ( to aid in follow up shots ), and with the right hard cast ammo will work.

Again this is just something offhand, but a handgun in a bear attack would be the last Hail Mary with any pistol / revolver - better make sure the firearm you choose works and ya can hit with it.

^
Again I admit I’m not expert in bear stuff or Big powered handguns ( did grow up shooting 45 Colt / 41 / 44 mag ), but never been attacked by a grizz so my mmv ! Thanks

[Sailormilan2]

The Glock 21 frame (45acp) is the same size as the Glock 20 frame(10mm). So, as was previously stated, all you need is a complete side assembly.
I converted my 45acp 1911 to 10mm by changing the complete slide. Of course, I also changed the Main Spring (Hammer Spring), but I am unfamiliar with the Glock’s so I can’t say that.

[Notpc]

The ejector on the G21 different than the G20, so with a slide swap/conversion you will also need a different ejector. For reliability reasons, I would probably just buy a factory 10MM handgun. I tried to soup up my 21 by buying a Lone Wolf barrel for better chamber support. But the Buffalo Bore hard cast 45acp rounds I bought would not work in the tighter Lone Wolf barrel. The OAL of the BB 45's is a tad longer and would not chamber. Stock 21 Barrel works fine with a 22lb recoil spring. Have you considered a Smith & Wesson M&P 2.0, 10MM? Probably a bit cheaper than a PPT'ed Glock 21.

https://www.turners.com/smith-and-wesson/smith-wesson-m-p-2-0-10mm-optic-ready-4-6-barrel-black-10-rnds-ca-compliant-1990082

[walmart_ar15]

There are standoff devices for autos that will allow slide contact without pushing it out of battery.