‘Looking at a Gen. 3 Glock 21 SF:

[Will Beararms]

Any feedback? Will Gen. 4 Glock 21 mags work with it? Thanks. 

[Quercus]

Yes the Gen 4 mags will work in it.

[Borg warner]

I have a Glock 20SF and I really like it The first G20 I bought was a Gen 3 G20C and as soon as I tried the SF I sold the 20C and got the SF. the difference in grip size made a huge difference for me. But I've heard that the Gen 4's with the smallest backstraps are the same as the gen3 SF's 

Edited July 4, 2018 by Borg warner

[nmgunshooter]

G21 is a great gun! Its my favorite!!!! It saved my life years ago.

[redrick]

I like the 21sf , a buddy of mine that I work with bought one and we meet at the range one day , this was his first time shooting it . I brought my 23 and 9mm 1911 and he brought his 19 , gen1 17 and his new 21sf . We traded off  pistols , he didn't like my 23 , he said it was radical . He said my 1911 felt like shooting a .22 . He handed me his 21sf and I was surprised at how accurate I shot it . It made me want one , that's a lot of .45 in a pistol and accurate .

[Citra47]

On 7/3/2018 at 9:07 PM, Borg warner said:

I have a Glock 20SF and I really like it The first G20 I bought was a Gen 3 G20C and as soon as I tried the SF I sold the 20C and got the SF. the difference in grip size made a huge difference for me. But I've heard that the Gen 4's with the smallest backstraps are the same as the gen3 SF's 

Both my G20 & G21 are Gen4 and fit my hand great. The older standard G20/21 felt too large for me to get a really good grip. 

[Borg warner]

5 hours ago, Citra47 said:

Both my G20 & G21 are Gen4 and fit my hand great. The older standard G20/21 felt too large for me to get a really good grip. 

I've never shot of even held a Gen 4 large frame Glock but from what I understand, with the smallest backstrap it's exactly the same as the G21 and G20 SF. I may eventually get a Gen 4 G21 if I don't end up getting a G21 slide assembly and barrel for my G20SF. Another thing I did with my G20SF that helped a lot was to undercut the trigger guard on the right side (Becaseu I'm right-handed) and slightly round off the rear of the trigger guard on the left side for shooting with the weak hand. And then I filed down the "Bumps" of the wretched finger grooves and left the checkering in-between.

These slight changes are not immediately noticeable but make a big difference in the way the gun  fits the hand. I was also reluctant to undercut the trigger guard on both sides for fear of making it too thin to where it might break.

[Citra47]

3 hours ago, Borg warner said:

I've never shot of even held a Gen 4 large frame Glock but from what I understand, with the smallest backstrap it's exactly the same as the G21 and G20 SF. I may eventually get a Gen 4 G21 if I don't end up getting a G21 slide assembly and barrel for my G20SF. Another thing I did with my G20SF that helped a lot was to undercut the trigger guard on the right side (Becaseu I'm right-handed) and slightly round off the rear of the trigger guard on the left side for shooting with the weak hand. And then I filed down the "Bumps" of the wretched finger grooves and left the checkering in-between.

These slight changes are not immediately noticeable but make a big difference in the way the gun  fits the hand. I was also reluctant to undercut the trigger guard on both sides for fear of making it too thin to where it might break.

Getting a gun that fits the hand is everything. I have learned to live with the finger grooves on the Gen 3 & 4 but got a new Gen5 G 17 and it feels like going back to the Gen1 & 2 without the soft plastic. I love it - especially the grip and trigger. The only drawback to the Gen4 is probably the trigger though I understand it can be replaced with the Gen3 trigger. I have just learned to live with it and don't think about it much anymore.

My Gen4 G 20 & 21 both go without any added grip panels making for a very nice grip for me. I too have read it is essentially the same as the Gen3 SF.   

[Boogieman]

Functionally there's no difference between the SF and the regular.  I have YUGE hands so I prefer the original recipe.  But if your hands are smaller it could be the way to go.

[Boogieman]

5 minutes ago, Citra47 said:

 The only drawback to the Gen4 is probably the trigger though I understand it can be replaced with the Gen3 trigger. I have just learned to live with it and don't think about it much anymore.

I installed a Gen 4 trigger in a Gen 3 G23.  The bump that everyone fears has been used in the large frame guns since the beginning.  I just polished the bump like I do with the larger guns during the .25 cent trigger job.  If there's a difference I can no longer feel it.

[Citra47]

1 minute ago, Boogieman said:

I installed a Gen 4 trigger in a Gen 3 G23.  The bump that everyone fears has been used in the large frame guns since the beginning.  I just polished the bump like I do with the larger guns during the .25 cent trigger job.  If there's a difference I can no longer feel it.

Thanks. I didn't know the bump had always been used in the large frame Glocks. I had a Gen3 G30 but traded it for a Gen4 G 26 because the grip was too large for my hand and I had not fired it much. That was before the G 30s. 

[L-2]

See next post.

Edited July 17, 2018 by L-2
Delete initial reply

[L-2]

Just now, L-2 said:

On 7/3/2018 at 5:28 PM, Will Beararms said:

Any feedback? Will Gen. 4 Glock 21 mags work with it? Thanks. 

The G21SF had/has three versions:

1.  One version had a Picatinny rail and ambi mag catch (now discontinued); the ambi mag catch needs G21 mags with a "window" cut into the front of the mags to engage the mag catch.

2.  Another version (also discontinued) had a more-or-less, standard Glock rail, but still with an ambi mag catch; again, the mags with a window cut into the front are required.

3.  The current and latest version omitted the ambi mag catch in favor of Glock's normal "right handed" Gen3 mag catch; any G21 mag will work with this version.

If buying used, it'll be important to know about the three versions.

 

[Fyrtwuck]

I have an early Gen-2 21 and a 21SF. There is noticeable difference in the size of the grips between the two. I took it a step farther. I did a slight grip reduction on my 21SF, removed the coarse checkering between the finger grooves and my son added fine stippling in it’s place. 

All Glock 21 magazines will work in all Glock 21’s as long as you don’t change the magazine release to the right side of the pistol. Being left handed, I adapted to a right handed persons world and always used my index finger for the mag release.