Finally got the 17 mos with RMR ready for its first range trip.

9/10 times it would not slide lock on the last round. Three different ammo types and 5 mags. Slide lock holds just fine when manually locked back.

When smacking in a loaded mag the slide also goes into battery more often than not. When inserting a mag I made sure all fingers were below the trigger guard and the slide still went into battery.

I had numerous Glocks over the years and have not had either problem. I removed the slide and inserted each mag and they are activating the slide stop without any issue.

I wonder if this could be from the ambi slide lock and my grip is hitting the lock??

This message has been edited. Last edited by: gpbst3,

It could be the grip, but there might also be a slide catch or spring issue. I’ve got quite a bit of time behind gen 5 Glocks, and I’ve never had a slide close when seating a magazine.

quote:

Originally posted by gpbst3:
When smacking in a loaded mag the slide also goes into battery more often than not.

FWIW, many people don’t consider that to be a problem. In fact, it is so common with many guns that many Glock shooters depend upon it (albeit sometimes inappropriately, IMO). The extra inertia of the RMR on the slide would probably make that more likely to occur. Automatic slide release like that is less likely if care is taken to insert the magazine with the force (“smacking”) directly in line with the magazine well rather hitting the grip so that the frame is driven forward during the process.

Although I have virtually no experience with Glocks, if you believe your grip might be interfering with the slide stop lever, it should be easy enough to experiment to check by loading just a single round in the gun and ensuring that your grip/fingers aren’t anywhere near the stop when you fire.

I believe it’s more likely, though, that the extra weight of the RMR on the slide is slowing slide speed and preventing its moving far enough to the rear after ejecting the last case to allow the slide stop to engage the intercept notch. I realize that Glocks are supposed to function properly with no lubrication other than congealed corn syrup and beach sand, but I always like my guns to be clean and well lubed with proper oil or grease. I don’t know either if lighter recoil springs are available for Glocks, but that’s something else I’d try.

Added: Well, of course as a little research revealed, reduced strength recoil springs are available for Glocks, so that would be something I’d try if my other suggestions don’t help.

Have you shot it before the RMR?

quote:

Originally posted by Nismo:
Have you shot it before the RMR?

Good question.
When I installed an R1P on my Legion, it interfered with slide velocity.
I had to do some recoil spring tuning to fix it.

Not sure if Glocks are different than other pistols on the slide lock on an empty magazine but it sounds to me like the mechanism between the magazine and the slide locking is not moving to the full locked position. perhaps just breaking the pistol down and checking the various parts of this for burs and then rubbing it all well might solve the problem.

quote:

Originally posted by DirectDrive:

quote:

Originally posted by Nismo:
Have you shot it before the RMR?

Good question.
When I installed an R1P on my Legion, it interfered with slide velocity.
I had to do some recoil spring tuning to fix it.

No I have not. I was too eager to try out the rmr. Never even tought the extrs weight of the rmr could be an issue.

I have a box of +p hollow points I might have to try out. Maybr the extra bang could compensate for the rmr.

It sucks the range is an hour away for trouble shooting.

quote:

Originally posted by gpbst3:
Maybr the extra bang could compensate for the rmr.

Please keep us posted on how it checks out.

Thanks for all the help guys.

Without another range trip, I think its either my grip or the rmr weight.

Other than the RMR, any other changes to the pistol?

A slide's failure to lock back is generally shooter-induced.

Shoot it one-handed to see if your support hand is interfering with the slide lock lever. Make sure the lone hand that's gripping the gun is clear of the slide lock lever.

Also ensure that you're using a strong grip/stance with your wrists locked when you shoot, since limp-wristing can cause this.

If neither of those more common shooter-related culprits resolve it, then start looking for mechanical causes.

quote:

Originally posted by kilyung:
Other than the RMR, any other changes to the pistol?

No its stock.

100 percent its your grip. The ambi slide lock is a lot wider than the previous generations.

Consider yourself lucky. Some guys are locking the slide back under recoil with rounds still in the magazine.

I was looking over the gun to check things out and saw the recoil spring is already 13lbs. Im finding non MOS glocks are 17lbs. It looks like they already compensated for the added optics weight.

Most likely its my grip.

Im not liking this at all, I never had this problem with any other Glock. Off to the interwebs to see if someone makes a conversion to a single sided slide stop.

I'm confused on the recoil spring issue. I see the same recoil assembly in my MOS and non MOS gun of the same model. Why do you think its a different part and rate?

Maybe bring some tools with you and you can shoot it with the rmr and with no rmr(just the plate cover) to help isolate the issues.

A friend of mine some years ago was complaining of the same thing with his Gen 4 19. It was super consistent and he thought there was something wrong with it. We went to the range and I said "I've got an idea." We loaded up every Glock magazine we had with us with a single round, and between the two of us, it was probably more than twenty. I went through all those mags and didn't have it fail to lock back once. Standard troubleshooting isolated the problem, which wasn't the gun.

quote:

Originally posted by gpbst3:
Im not liking this at all, I never had this problem with any other Glock. Off to the interwebs to see if someone makes a conversion to a single sided slide stop.

Failing that, you could probably roll your own and take a dremel or a file to it to remove the offending section.

quote:

Originally posted by hrcjon:
I'm confused on the recoil spring issue. I see the same recoil assembly in my MOS and non MOS gun of the same model. Why do you think its a different part and rate?

I google glock 9mm recoil spring weight and kept seeing 16-17 lbs. When I checked my spring for the mos it was 13. I assumed it was a lower weight to offset an optic

I'm only seeing one spring for the G17 Gen5 which is 17 lbs, never seen it specify MOS or non MOS.


About slide weight- The RMR RM06 weights 1.2 oz. (34.02g)

I'm wondering if the weight of the RMR is greater than or lesser than the weight of the steel removed from the slide plus cover plate, and if so, by how much?

quote:

Originally posted by Nismo:
I'm only seeing one spring for the G17 Gen5 which is 17 lbs, never seen it specify MOS or non MOS.

My spring is labeled 13. Im assuming that is the weight, right?