Glock 21sf 45 acp to 10mm drop in barrel or G20 slide asmby.

[WB300]

First off, to the Mods... I was reluctant to start this thread, but based off of a similar thread in the Private Section, I'll give it a try. I will immediately delete if it crosses the line. For those without access to the Private Section, please don't derail this with content unrelated to my Glock question.

I have a Gen 3 G21sf in 45 acp. I got it back in the day when companies made a drop in barrel to allow it to shoot 10mm, but didn't buy the barrel. Now that my other projects are caught up, I can revisit this. Problem is... newer Glock 45 acp models are more conducive to drop in conversion barrels. Phone calls to Lone Wolf, KKM...etc revealed that they would have to be special order, but they don't have time because of demand for catalog items. Does anyone know of a dealer or manufacturer that has or still makes this drop in conversion? I already have the extractor, recoil spring, and mags.

EDIT: Apparently a Gen 3 G20 (10mm) slide will work on the G21sf, but Lone Wolf and KKM are out of stock. Does anyone know who has the slide only or complete slide assembly in stock?

Let me be clear.... this is NOT a back door WTB in the PX. I am interested in new (retail) and don't want to take a chance on some garage/dremel modified crap. I guess it's more of an "availability" thread. My hunt in bear country is coming up.

@MarinePMI
@Dthomas3523

Thanks in advance,

Will

 

[fdkay]

First off, to the Mods... I was reluctant to start this thread, but based off of a similar thread in the Private Section, I'll give it a try. I will immediately delete if it crosses the line. For those without access to the Private Section, please don't derail this with content unrelated to my Glock question.

I have a Gen 3 G21sf in 45 acp. I got it back in the day when companies made a drop in barrel to allow it to shoot 10mm, but didn't buy the barrel. Now that my other projects are caught up, I can revisit this. Problem is... newer Glock 45 acp models are more conducive to drop in conversion barrels. Phone calls to Lone Wolf, KKM...etc revealed that they would have to be special order, but they don't have time because of demand for catalog items. Does anyone know of a dealer or manufacturer that has or still makes this drop in conversion? I already have the extractor, recoil spring, and mags.

Let me be clear.... this is NOT a back door WTB in the PX. I am interested in new (retail) and don't want to take a chance on some garage/dremel modified crap. My hunt in bear country is coming up.

@MarinePMI
@Dthomas3523

Thanks in advance,

Will

You might have to consider some 185 +p .45 ammo. Should do pretty well.
Do you reload? If, so, a 185+P loading with the XTP bullet will penetrate deeply.
Have you tried sourcing 10mm ammo? Be aware, that much of the ammo, if on the shelves, is the "medium power" loadings (ie = .40 S&W).

 

[WB300]

Thanks for the response fdkay. I have 45 dies, but no components. A buddy has some factory 10mm heavy hitters like Corbon, Buffalo Bore, and others that he would give me. I don't want to shoot lead... just jacketed.

But I guess you brought up another option.... Commercial loaded 45 +P or similar stout loads. I still want stout 10mm, but stout 45 could work in a pinch. I almost went 460 Rowland, but those need a brake to function reliably and I don't want a brake. Not too concerned about recoil as I have a pretty good grip.

 

[fdkay]

Thanks for the response fdkay. I have 45 dies, but no components. A buddy has some factory 10mm heavy hitters like Corbon, Buffalo Bore, and others that he would give me. I don't want to shoot lead... just jacketed.

But I guess you brought up another option.... Commercial loaded 45 +P or similar stout loads. I still want stout 10mm, but stout 45 could work in a pinch. I almost went 460 Rowland, but those need a brake to function reliably and I don't want a brake. Not too concerned about recoil as I have a pretty good grip.

right now, getting anything is difficult.
However, if you can find a Pistol chambered in 10mm, you might be better off just buying a new pistol.
EAA makes a really nice CZ75 clone in 10mm, you can sometimes find the S&W 610, cool thing about that is you can shoot .40 S&W in it as well.

Don't forget the tried and true .41 and .44 magnums.

 

[elwarpo]

Have you considered a g20 slide so stock barrels work. Lone wolf makes them.

 

[WB300]

Have you considered a g20 slide so stock barrels work. Lone wolf makes them.

So... a Gen 3 G20 slide assembly will work on a Gen 3 G21sf?

 

[WB300]

So apparently it will, but Lone Wolf is out of stock. Grrr!

I am going to ammendment the thread to include slide assemblies.

Thank you elwarpo.

 

[elwarpo]

Pic of a Gen 2 on a SF, gen 3 should fit the same. Order from LW and wait. They get them made from an outside company and do final milling work. They are sold out before they get online, so placing an order is the best bet since you can cancel it if you find something.

 

[mrtoyz]

I’ve been looking for a 20 slide for my Gen 3 21 for year’s. The ones I’ve seen go for $550+. Ouch. I’ve just about given up

 

[Pre64]

If you are an active or retired first responder or a veteran you can buy a new Glock 20 for $485 On the blue label program, If you not one of those join the gssf program for $60 and you will get 2 coupons to buy at the blue label price.

 

[elwarpo]

Don't know about Rocky Brass Slides, but 299 for a rmr cut G20 slide. Posted another thread to see if they are GTG.

 

[Yondering]

So... a Gen 3 G20 slide assembly will work on a Gen 3 G21sf?

Well, yeah, the frames are the same.

I went down the road you describe back when the SF frame was new, and have done all of what you've asked about above. Long slide "G20L" upper, drop in 10mm conversion barrel, and just plain G20 10mm barrel.

Your best option is a complete factory Glock G20 top end if you want to keep the stock slide length. The 10mm slide is heavier than the .45 slide, and for good reason, although that only matters if you're shooting actual full power 10mm and not the common light loads.
Only reason I see to go with a Lone Wolf slide is if you want to make a long slide, basically a G40 in gen 3 flavor. (FWIW my Lone Wolf long slide, complete, weighs almost exactly the same as a new gen 4 G40 top end, within a few tenths of an ounce. Better to just buy a G40 IMHO.) You do take a significant chance on giving up some of that Glock reliability, which is the main reason to buy a Glock in the first place.

The 10mm conversion barrels work fine, but slide velocity with the G21 slide gets pretty high with top end 10mm loads and I prefer not to feed it a steady diet of them. (The G40 or my old gen 3 long slide can use those same loads all day long.)

The easiest method is to just drop a G20 barrel in your G21 slide. The barrel hood is too narrow to align itself, but the external flat sides of the barrel do that in the slide. I did exactly that for a few years before picking up a 10mm slide, and never had a single issue. Accuracy was good, and I do mean good, I'm not one of those guys who shoots pie plate groups at 10 yards and thinks it's "good".

Hope that helps.

 

[WB300]

The easiest method is to just drop a G20 barrel in your G21 slide. The barrel hood is too narrow to align itself, but the external flat sides of the barrel do that in the slide. I did exactly that for a few years before picking up a 10mm slide, and never had a single issue. Accuracy was good, and I do mean good, I'm not one of those guys who shoots pie plate groups at 10 yards and thinks it's "good".

With what little I've found on that, you are the only one who said it functioned reliable, but there could have been other contributing factors. I hunt in WY mountains every year, so reliability has to be there. Thank you for the info.

 

[mrtoyz]

Well, yeah, the frames are the same.

I went down the road you describe back when the SF frame was new, and have done all of what you've asked about above. Long slide "G20L" upper, drop in 10mm conversion barrel, and just plain G20 10mm barrel.

Your best option is a complete factory Glock G20 top end if you want to keep the stock slide length. The 10mm slide is heavier than the .45 slide, and for good reason, although that only matters if you're shooting actual full power 10mm and not the common light loads.
Only reason I see to go with a Lone Wolf slide is if you want to make a long slide, basically a G40 in gen 3 flavor. (FWIW my Lone Wolf long slide, complete, weighs almost exactly the same as a new gen 4 G40 top end, within a few tenths of an ounce. Better to just buy a G40 IMHO.) You do take a significant chance on giving up some of that Glock reliability, which is the main reason to buy a Glock in the first place.

The 10mm conversion barrels work fine, but slide velocity with the G21 slide gets pretty high with top end 10mm loads and I prefer not to feed it a steady diet of them. (The G40 or my old gen 3 long slide can use those same loads all day long.)

The easiest method is to just drop a G20 barrel in your G21 slide. The barrel hood is too narrow to align itself, but the external flat sides of the barrel do that in the slide. I did exactly that for a few years before picking up a 10mm slide, and never had a single issue. Accuracy was good, and I do mean good, I'm not one of those guys who shoots pie plate groups at 10 yards and thinks it's "good".

Hope that helps.

If only it was possible to find a factory/barrel slide that didn’t cost more than a complete gun

 

[fdkay]

Ruger GP100 10mm Wiley Clapp Special Edition Double-Action Revolver

Ruger: GP100 10mm Wiley Clapp Special Edition Double-Action Revolver for sale at Sportsman's Outdoor Superstore.

www.sportsmansoutdoorsuperstore.com

 

[Yondering]

If only it was possible to find a factory/barrel slide that didn’t cost more than a complete gun

True. But anyway, the best way to go here, by far, is a complete new G40. More velocity, easier aiming, and they control heavy loads better than the G20 or 5” 1911. But best of all, the reliability is there, even with top end loads. That extra slide mass is worth a lot in this application.

 

[Yondering]

With what little I've found on that, you are the only one who said it functioned reliable, but there could have been other contributing factors. I hunt in WY mountains every year, so reliability has to be there. Thank you for the info.

If you’re lumping reports of 9mm barrels in a 40 slide in with that, forget it, they are totally different things.

The 10mm and .45 barrels are the same dimensions on the outside, other than the hood. Look at your 45 barrel in the slide, and how it’s constrained by the side flats; the 10mm fits exactly the same way. I don’t know about other things you’ve read, but it worked reliably for me in a couple different guns and 4 different barrels. No reason why it shouldn’t.

Im not saying it’s the best way to go, or even recommending it, but it does work in a pinch.

 

[sam4886]

@Yondering what spring are/were you using on the g20 long slide? I've got a lone wolf made g20 long slide with threaded barrel on a p80 lower that I think could benefit from something a little stiffer.

Lone wolf sold me a standard g20 spring with a little plastic washer thing they called a spacer and I'm not even sure I have it set up right. they didn't include directions and I couldn't get any answers online. I have the spacer on the front end of the guide rod between the spring and the end of the rod. In other words, I took the rod apart to add the spacer too it.

 

[Yondering]

@Yondering what spring are/were you using on the g20 long slide? I've got a lone wolf made g20 long slide with threaded barrel on a p80 lower that I think could benefit from something a little stiffer.

Lone wolf sold me a standard g20 spring with a little plastic washer thing they called a spacer and I'm not even sure I have it set up right. they didn't include directions and I couldn't get any answers online. I have the spacer on the front end of the guide rod between the spring and the end of the rod. In other words, I took the rod apart to add the spacer too it.

I use a 22 lb ISMI spring on a captured guide rod. My standard load for that long slide is a 200gr hard cast at 1,375 fps.

For the Gen 3 units there is a small washer that needs to go between the spring end and the screw, but another common spacer you’ll see is for using Gen 3 guide rods in Gen 4 slides. That one is sort of a hat section shape.

 

[sam4886]

Copy that. Sounds like I have the spacer installed right then.

I'll do some research into spring rates. The plan is for the 10mm to be a black bear getter so it'll be shooting heavy stuff too.

 

[Yondering]

Copy that. Sounds like I have the spacer installed right then.

I'll do some research into spring rates. The plan is for the 10mm to be a black bear getter so it'll be shooting heavy stuff too.

The spring rate thing is simple - you can go straight up to the maximum 24 lb, or 22 lb, doesn’t much matter, if you’re shooting heavy loads and have a solid wrist. There isn’t much point in going lighter; it should still cycle the mild loads too even with the heaviest spring. I can run 40 S&W through mine reliably, although I don’t see much point.