X300 on Glock using Rail Lock

[og556]

I have an X300 I mounted on my Gen 4 G19.

I previously shot 200 rounds through this pistol with the X300 mounted and it has not induced any failures using the standard quick detach mount.

Today I installed the Rail Lock "U" mount which is a semi-permanent mount. I like the idea of a stronger more solid mount with no play to induce failures but I noticed a problem.

When you install the rail lock you pull back on two tabs and pull the lock bar out enough to slide the light onto the pistol. After sliding the light on the pistol you have to take an allen wrench and tighten this screw which raises a tab against the bottom of the dust cover which puts pressure on the dust cover to help secure the light.

Now with this screw tightened down far enough to prevent the light from shifting at all by hand I notice the lights bezel is just a tiny bit angled up at the front and the rear is angled down a tiny bit.

I feel like this could cause issues with a polymer framed gun but if I loosen it and only tighten to a point where it moves by force it may not be strong enough ?

Should I just go back to the quick detach solution which has play any way ?

I would appreciate any feedback.

[operator81]

I have yet to see a X200/300 series Surefire come off the rail using only the quick detach lever. I think you'll be just fine using the quick detach.

[R0CKETMAN]

Shim it or shoot it. Your Glock will be just fine.

[og556]

I'm actually more concerned about malfunctions than retention.

Is it worse for reliability to have the light tight against the rail on a Glock and use that rail lock with the tension screw or is it better to allow a looser fit and allow the light to shift back and forth.

The frames on Glocks feel like they use a softer polymer than others such as walther and HK. Im not worried at all about scratching or gouging just about reliability.

With the quick detatch mount it shifts back and forth with ease. I have the U plate installed and have played with adjusting the six rail mount screws but the QD mount is loose no matter what.

The rail lock is loose until you tighten the tension screw in almost all the way till it stops. I feel like this could effect the reliability of the gun. I will try calling Surefire on Monday to ask some questions too.

[donlapalma]

How about shooting it to see if you have any issues??? If you have issues go back to your original setup.

[og556]

I have about 400 rounds I'm going to put through it tomorrow with the rail lock installed. I just wanted to see if someone had any first hand experience with this situation.

One interesting observation was that with the U rail lock installed when I tighten the tension screw just to the point where the light wont budge by hand I can still slide it off without unscrewing the tension screw.

So many variables. Sorry if I'm over thinking this gents.

[og556]

Just an update guys.

Today I hit up the range with to see how the gen 4 G19 would work with the X300 + rail lock system.

I had brought 400 rounds of assorted 9mm with me. 200 of WWB 115gr, 200 of federal 9mm 115gr.

The magazines were all the newest ones I had (good, new springs).

I loaded the first couple of magazines with 5 rounds.

During slow fire I had 1 stovepipe but the following round made its way almost into the camber (would have fed if there wasnt a stovepipe).

I think the slide may have been moving too fast. I had more erratic ejection patterns than I did with the QD with the X300.

After this failure I shot a few more magazines which were mostly downloaded to 5-10 rounds. I had one other similar failure as well.

So thats two similar stovepipe failures.

For what its worth both malfunctions occurred with the WWB ammo. I have never shot WWB ammo through this G19 before and I understand its very weak and dirty.

Now I must admit I have never had an FTE or FTF with this gun before and for a gen 4 it has pretty consistent ejection patterns.

I also shot the gun left handed (I'm a righty) and did not induce any failures with 30 rounds shot this way.

I ended up firing only 200 rounds this trip as I wanted to save the other two hundred rounds for further testing with the QD attachment that originally came with the X300.

Also after shooting with the rail lock I noticed that even though the tension screw was in pretty far and it was damn near impossible to move the light back and forth by hand after this range session the light was shifted forward a little bit and had loosened up on the rail.

[ArmaGlock]

I use the quick detach on my x300 attached to my Glock 22....Mine would shift back and forth pretty easily as you describe. To remedy the problem, I removed the 6 screws that hold the two rails onto the X300, applied blue loctite and put them back in. To eliminate the play, I put the light on the gun before I tightened down the screws. I then tightened the screws down with the light on the gun while applying inward pressure to the outside of the rails on the X300. Doing that eliminated the play. If you apply too much pressure it will be difficult to take the light on and off.

Here's a picture showing where I'm talking about applying the pressure when tightening the screws while the light is attached to the gun. You could do it without the light on the gun, but you will probably end up making them too tight and it will be a pain to slide on the rails of your pistol. You just have to play with it, but you can eliminate the play in the light while keeping the quick detach mount.

http://i1212.photobucket.com/albums/cc455/armaglock/X300fix.jpg

[ddnguyen9]

Should I just go back to the quick detach solution which has play any way ?



I have a Glock 30SF Gen 3 with a Surefire X300. I have shot probably 1000 rounds though this firearm. I always used a quick detach option on the light. I have never had an issue. I recently upgraded to a X400. So far no issues as well.

I carry a Glock 21SF Gen 3 as my on-duty sidearm with a Surefire X300. Once again, no issues whatsoever. I would say about 3000+ through this this Glock.

So IMHO, the quick detach is the best option. Easy off for cleaning and maintenance (battery replacement, cleaning, etc.)

[og556]

After re-attaching the QD system this last Sunday I put about 300 rounds of WWB and Federal 9MM 115 grain FMJ ammo through the G19.

Overall the performance was OK. The ejection was a little weaker than without the light installed but I had zero malfunctions firing right or left handed.

During rapid fire drills I did notice the ejection was especially weak for some reason. If I shot off a string of 5-10 shots extremely quickly the brass would sometimes hit me in the head.

During normal slow fire the ejection was weaker than without the light but overall OK.