[Chris Larson l]

Hi all, new to the site and hoping someone here can help me.

I recently converted my G21 to a 10mm. Today I went to the range, and got misfeed with every round.

Here are the details -

Mags - G20 Stock Mags
Barrel - Lone Wolf Alpha Wolf 10mm stock length barrel.
Recoil Spring - 20lb Stainless Steel Recoil Spring from glockstore

These are all the parts recommended in this article -
https://www.thetruthaboutguns.com/frankenglock-10mm-45-glock-21/

I tried two mags worth of Blazer 180 Grain. Every round was a misfeed. Should I go back to the stock 21 recoil spring? Could it be the mags?

I’m scratching my head on this one. I really want this to be my truck gun so I could use the help.

Thanks,
Everyone

 

[mtstream]

Can you give more description of “misfeed”. What did you actually observe? The spent shell was still in the chamber, the next round didn’t get picked up, round jammed against the feed ramp, etc etc.

Was it consistently the same issue?

 

[Chris Larson l]

Can you give more description of “misfeed”. What did you actually observe? The spent shell was still in the chamber, the next round didn’t get picked up, round jammed against the feed ramp, etc etc.

Was it consistently the same issue?

The spent casing was not ejecting before the next round could follow. Next round was picked up but basically pinched the spent casing in the chamber unable to eject.

 

[mtstream]

Good to know. The position of the spent casing in the chamber could give clues as well. It sounds like the spent casing appears to not have been removed from the chamber? This would indicate a problem with the extractor. If the spent casing did a stovepipe (tried to eject but bounced around in the gun then got caught by the slide in a vertical position) it is possibly an ejection issue that could be related to the RSA.

I expect based on your post that the empty stayed in the chamber as this is not uncommon with .45 to 10mm conversions. The normal tolerances in a G21 can result in the extractor having difficulty gripping the rim on a 10mm round well enough to consistently extract it.

Other than knowing the issue appears to be extractor related and this is a fairly common problem with the conversion - I’m not knowledgeable about resolving it as I don’t do this conversion. I would first inspect the extractor for any possible damage that might cause the problem. If it’s a tolerance issue, there may not be a great answer.

Search for GRT45’s posts about converting the 21 to 10mm. They’re pretty extensive.

I would also give Lone Wolf Distributors a call and see if they have any recommendations.

 

[mtstream]

Looking back I see you mention wanting it to be your truck gun - personally, I wouldn’t trust my life to a conversion. As a 45acp the 21 is a really great self defense gun.

 

[Chris Larson l]

Looking back I see you mention wanting it to be your truck gun - personally, I wouldn’t trust my life to a conversion. As a 45acp the 21 is a really great self defense gun.

Much appreciated. I’ll keep doing some digging to see what I can come up with. I really wanted this to workout for a truck gun or hunting side arm. If all else fails I’ll go back to stock G21 and leave it be.

 

[Scott60]

You might need to mod the extractor a bit to swing it about half a millimeter further inboard. There is a small "pad" on the inside that contacts the extractor slot "bottom". This can be carefully stoned down to allow the extractor to move in a get a better grip.

As I remember it, the extractor for a G20 slide will not fit a G21 slide. The 10mm rim is around 1.4 mm smaller than .45 ACP which is positively "yhuge" in extractor land. The empty case is shifting toward the opposite side as it clears the chamber, and as it passes over the cartridge being lifted, it being "bobbled" from under the extractor, thus leading to the situation you describe. The loose case ends up jammed in the port with the next round attempting to chamber.

 

[NoJoy]

Interesting. I have a KKM 10mm conversion barrel for my Glock 41. Other than a tungsten guide rode (factory spring rate), and G20 mags, no other upgrades. (stock extractor)
I’ve shot over 200 rounds of 10mm & about 50 rounds of 40. No malfunctions yet.

 

[sportsnut44]

the answer to (noJoy) is the kkm is great quality, the lone wolf never works for me. i sold all of my lone wolf barrels and my problems went way.

Interesting. I have a KKM 10mm conversion barrel for my Glock 41. Other than a tungsten guide rode (factory spring rate), and G20 mags, no other upgrades. (stock extractor)
I’ve shot over 200 rounds of 10mm & about 50 rounds of 40. No malfunctions yet.

 

[Sigma40sw]

Question: What vintage G21 are you trying to do this with, Gen 2 or Gen 3. The early G21's have a straight ejector, Gen 3 ejector's are offset inboard more. You may need to install a 10mm ejector because the early 45 ejector is not contacting the loosely held 10mm case.

 

[Borg Warner]

There's only one way to convert a G21 to a 100% RELIABLE 10mm and that's by getting a complete G20 slide and barrel and putting it on your G21 frame.

Whatever the cost difference is between doing that and trying to make a conversion barrel function 100%, it's worth every penny of it. Buy once, cry once.

 

[xdmikey]

When I did the conversion I used a KKM barrel and was advised to file a bit of the hood(iirc)to enable the round to make the jump. It makes more sense to file the ramp but I don't remember it that way.

 

[MinervaDoe]

If all else fails I’ll go back to stock G21 and leave it be.

That's the best idea that I've heard so far in this thread.
My gunsmith wanted to do the same thing as you. So, he bought a complete Glock 20 slide and stock barrel for his G21 frame. This is how an expert gunsmith accomplished the conversion you want to do. :whistling: Just sayin' ....
You do know that the Glock 20 has a slightly heavier slide than the Glock 20, right?
That's the difference between an empty G20 (@ 30.51 oz) vs and empty G21 (@ 29.1 oz). About an ounce and a half to offset additional recoil.

 

[DC1970]

You might need a different ejector. Which will mean you need a new trigger mechanism housing. I was thinking of converting my g44 from .22LR to 9mm and that's one of the things I would need to do along with a new locking block. You might as well just get a whole new trigger assembly so you can just drop it in instead of taking it all apart just to replace the ejector pin.

 

[BarryR]

By the time you buy all the parts/slide ect. you might as well but a new gun.I'm sure the price will be close. Just my 2cents

 

[DC1970]

Looking back I see you mention wanting it to be your truck gun - personally, I wouldn’t trust my life to a conversion. As a 45acp the 21 is a really great self defense gun.

 

[DC1970]

A "Truck Gun" is generally considered to be a gun used to put-down an injured animal that has been hit by a vehicle. It doesn't have to be a high caliber as a 10mm. A .22LR to the temple is enough to kill the wounded animal. Another thing about truck guns is that it is best to not have a gun in your car or truck that you wouldn't want to have stolen as it probably will be stolen if you just leave it in your vehicle all the time. I would suggest using an inexpensive rifle as a truck gun as it is less likely than a pistol to be used in a crime if it gets stolen out of you truck or car.