Glock 21SF issues...

[Socal858]

Many times, someone will try "Home Gunsmithing" because they like to tinker & think they can spend a few dollars & "improve" a gun after the manufacturer spend hundreds of thousands of dollars on design & testing. Or, they're thinking "modifications" will magically make them a better shooter.

Then, (as you discovered) when the gun no longer works, they'll sell the screwed-up gun & use the magic "Customized" word on some unsuspecting buyer.

Precisely. Glock / HK / Sig aren't morons, they don't pay their engineers to sit around and send kissy faces on social media to each other all day.

"Customized" guns are often crap and you see them on the market when sellers are either tired of troubleshooting the Pandora's box they've opened by breaking their gun, or think their special snowflake modifications have now increased the guns value and want a sucker to pay full price so that they can cash out and modify/destroy another firearm.

OP, find a Glock Armorer near you and replace everything with stock parts. It'll run just fine afterwards.

[HKMadness]

Make sure you find a REAL certified glock armorer, not just some guy that took the class so he can brag about being a CGA. I bought a glock off a guy that was going on and on about being a CGA, but had no idea what I was talking about when I was asking him about the finish.

[HKMadness]

Just seems like something very basic that certainly should be covered, regardless. I'd be very leary of a CGA that was totally clueless about finish anyway.

[kmas]

Cleaned Yet?

Did you clean out the firing pin channel?
That is a first and easier step to take before messing around with parts replacement.

If all else fails (including your contacting Glock) go to an armorer.

[1911su16b870]

Remove the slide from the frame. Press in the FP block plunger and shake the slide. You should be able to hear the FP moving back and forth inside the slide. If you don't hear movement, your FP channel is gunked up as stated above.

[splithoof]

Precisely. Glock / HK / Sig aren't morons, they don't pay their engineers to sit around and send kissy faces on social media to each other all day.

"Customized" guns are often crap and you see them on the market when sellers are either tired of troubleshooting the Pandora's box they've opened by breaking their gun, or think their special snowflake modifications have now increased the guns value and want a sucker to pay full price so that they can cash out and modify/destroy another firearm.

OP, find a Glock Armorer near you and replace everything with stock parts. It'll run just fine afterwards.

^^^WINNER, WINNER, WINNER!
One of the BEST posts I have EVER seen here on Calguns.
I've been lucky enough to put well over 25K through a G21, and also a whole bunch through a good variety of Glock products including 21SF, 30S, 19, etc. Troubles? None. The truth is exactly as quoted above; too many folks fiddle and mess with things they have no business touching.
Shoot it a lot, clean it when necessary, and shoot it some more. Done.

[liberty47]

Frog lubed?

[Tri750]

WHERE ARE YOU LOCATED?

[meno377]

Light primer strike usually caused by dirty firing pin channel.

This or the original owner changed out the firing pin spring with a lightened one.

THESE^^^

[Galli1565]

Clean it. Replace the springs and connector with stock glock factory parts. I suspect that you have a "lightened" striker spring and lord knows what else was done.

If you don't know how to do that, take it to your local glock armorer for replacement of ALL the internals. Depending on what "polishing", "trigger jobs" or "enhancements" may have been done. A six pack and a Dremel have ruined many a glock.

At this point you don't know what's in the gun. Change it back to stock before you try and shoot it again.

[DFence]

The issues persisted with some reloads which I've been using in my 1911's for years, as well as with factory WWB. I've tried cleaning out the channel to no avail. A friend suggested contacting Glock citing this article from 2005:

http://articles.latimes.com/2005/nov/26/local/me-guns26

OP, I am a Glock Armorer located in N. OC

If you are close, you can bring the gun over and I will detail clean it and return all the parts back to factory at no charge!

If you are not in the area, you can ship the gun to me as well and I will do the same. PM me if you are interested.

[HKMadness]

I wouldn't any more than I would be leary of a factory certified automotive mechanic being clueless about the paint finish on an automobile.

The better analogy would be a HONDA certified technician not knowing which particular finishes (out of only a handful) Honda (glock) has used in production.

The context of my comment as recorded is of a guy selling me his "Honda" and boasting about his "honda" credentials, yet unable to tell me which finish is on his "honda". A legitimate glock armorer should know glocks if they're gonna be paid to work on one of mine. Just saying having the CGA doesn't automatically mean what some might think it means, and good ones will have good reviews. That's all.

[longrifle1]

Clean the firing pin channel......bet that fixes it for you

[bk23103]

Update: I had the firing pin spring traded out for the stock one, and this eliminated the light strikes; however, I then noticed several failures to eject. I polished the chamber, and had no further issues save for when my 60 year old mom shot it. She had one light strike and a failure to eject. I am hoping her loose grip had something to do with this as I could not replicate the issue.

One thing is for sure. This gun is accurate!

[Libertarian71]

Update: I had the firing pin spring traded out for the stock one, and this eliminated the light strikes

Good to hear. Switching back to the stock firing pin spring will usually cure the problem.