I haven't owned a Glock in over 20-years, but bought a new Glock 19 G5 yesterday. I took it home, dissembled the Glock, cleaned the barrel, inspected the parts, oiled and reassembled.

So off to the shooting range I went with 50 rounds of factory 115 gr. ammo to sight in the Glock. The first three rounds went fine, then it started to jam on almost every other round, loading the stripped round about 50% of the way into the barrel. I finally made it through the first mag and I noticed it didn't lock back on the last round. I then tightened my grip and the Glock started to cycle fine and started to lock back on the last round.

I am familiar with what limp wrist problems are with pistols, but my normal grip has always been just fine with many other pistols that I have owned over 30-years, never having a problem with any of them.

So, my question is, are Glock gen 5's noted to sometimes be extra tight until they are broken in? If so, how many rounds is considered broken in?

I really like the way the new pistol shoots other then requiring a strong grip. None of my prior Glocks ever required a strong grip and they never failed.

Update 03/4/21

I made it back to the shooting range today. I started off shooting 15 rounds of 115 grain factory loads, and had two jams. Then I switched to a mag of Winchester 147 grain and had no malfunctions. The Glock felt different (better) at the last of the of the mag and the pistol cycled much better. I then switched to my reloaded rounds for a mag, no failures, then switched back to the 115 grain ammo factory loads and no failures.

So, I consider my Glock to now be dependable, with a little more verification just to make sure.

I can't totally explain what changed except that maybe the pistol just needed a few more rounds through it. Perhaps a burr, or just being a bit tight because it was new.

I am very happy!

Accept you are getting older, and your normal grip is not the same as it was over 20 years ago.

Thank you for taking the time to answer my question.

It is possible for them to send out a lemon... but they are test fired at the factory.

Have someone else shoot it with the same magazines and ammo and see what happens.

I have had tons of people with "broken Glocks" (including BTF) that I could not get to replicate the reported malfunction.

Thanks AJSully.

I don't consider this Glock to be broken, I am just surprised it requires a stronger grip then I am used to to get it to run right.

I guess I will find out if there is a break in period for this Glock. Lucky I have the ammo for it, and the time.

I have several.  None have performed any differently than previous generations as far as break in.

Use full power ammo or work out more.

Unfortunately Glock ( and just about all the other companies out there) are making guns that seem to require more break in than they used to.
I won’t go into limp wrist already covered
Also most will say glocks are designed around full power service ammo and at least initially may be functionally marginal with light 115 grain bargain ammo.
My personal story:
Had my long used reload that worked in a large variety of 9mm pistols including a well used gen 2 model 19.(load was middle of the road for powder charge)
Got a new 26 (gen 3) and it would not function with my load.
Had to boost load to .2 grains below max to run it.
About 500 rounds later, tried my original lighter load and it ran fine.

I have had a similar experience with a Polymer 80 940CL build using a G17 slide. My lighter reloads that worked fine in all other pistols would not function 100% in the new build. I did the same and bumped up my powder charge by 0.3 grains and shot  several hundred rounds before going back to my lighter loads.

What does "factory 115gr ammo" mean?

Glock bumped the recoil spring strength a few years ago. Sometimes it takes at least standard pressure rounds to get going good. I use full power 124gr NATO pressure rounds. Lots of factory ammo is on the weak side

Thanks to all for the replies and large amount of information. I am satisfied that my Gen 5 will cycle just fine after 500-600 rounds or so.

In the meantime, I guess I need to start some grip exercises! Maybe that would be "Gripping Iron".

Use full power ammo for several mags.

I have several 9mm's that hiccuped with weak ammo when they were new
including my 17L g3, 19C g4, G26 g4 and another 19 but now i forgot which one it is.

I attribute the hiccup with G26 as operator head space. It's flawless now.

My 17L, I used two boxes of the 124gr NATO. It now eats whatever you feed it.
I haven't done that yet with the 19C g4. It's not one I pickup very often.

ETA: remember that Glock 9mm's are designed for NATO loads.

I really wasn't ripping you. I'm in my 60's, and I don't shoot as well as I did when I was younger, and when someone else was paying for ammo.

I have some Glocks. 19s, 17s, 26, 43, 23, 45

Usually take them out right away and fire 200rds of whatever I grab.

Field strip clean and lube also before the trip

Haven’t had an issue yet except that Winchester “forged” with ETS magazines. The steel cases were rough and getting stuck on the inside of the mags.

I'm sure it's possible but I've had around 40 Glocks, never one problem from the factory, regardless of ammo. Maybe I've been lucky...

I had this happen a few times, with my G26...Just tighten the grip, like you did and will be fine.  IMO, ploymer or not, all things mechaincal require some "loosen up" time and rounds.

I will try to get back to the shooting range tomorrow, and I plan to shoot 50 rounds of 115 grain, and 50 rounds of 147 grain ammo. I will also take some of my reloads to see how they feed, although I don't expect much from my reloads as they are loaded at less power then factory ammo. Still, will be interesting to see how my reloads do.

I'll check back in here in a couple of days and hope to have shot around 500 rounds through my Glock at that point.

Thanks again to all who replied!

I've never had a malfunction with a Glock.  They have always fed, fired and ejected anything I put in them.  Now with that being said, as another person asked, what brand was your 115 gr factory loads.  You stated the 147's were winchester then you referred to your handloads... but specifically what was the ammo that failed?  I've never heard or seen a Glock that needed "broken in" or one that was "tight".

Not all factory ammo is created equal for sure.  Did you check for bulges in the cases?  Were bullets seated straight?  I've seen some pretty trashy "factory" ammo with these problems gettin by the QC

KrazyBlade,

I did an update today to my original post. All is well!

My first shots were with Fiocchi 115 grain ammo that I have owned for over a year. It has shot well in other pistols I own. Looks to be good ammo.

I fired some 147 grain Winchester today and by the end of one 15 round magazine of it, I could tell a noticeable difference in the Glocks cycling. From that point on no problem with Blazer 115 grain (brass case), or my hand loads. I would have shot more rounds but I needed to drift the sight a bit for accuracy so I returned home. I will try the Fiocchi again later this week, but I really don't think it was a ammo problem. I'm going to go with it just needed some more rounds to get things in sync.

For years now, when I get a 'new' Glock, I always
start it with hot ammo.

As I stated above, I've had three (G26 doesn't count-it was operator)
out of many hiccup and was told to use hot ammo starting out.

That was two decades back lol. Works like a charm. The 9mm is
made to use NATO rounds.

I buy and shoot Glocks specifically because they eat anything I shoot, including Wold and Tula steel case.
I've never had to break in a Glock.