Heavy optics and reliability

[GJM]

Another WHO failure to extract malfunction with my training G19.5/509 today. Identical conditions to the last time: 115 gr. Magtech, towards the end of the session (total round count was 250, 200 through the G19), with only a few rounds left in the magazine. Same combo earlier in the session had no issues, so suspect shooter fatigue played a role.

Went ahead and pulled the trigger on another 509 for the nightstand G47. Had an ACRO in the cart a few days ago, but this thread combined with my WHO issues made me decide that increased weight could just be inviting problems.

I ended up realizing that my Gen 4 22 was less reliable with hard cast ammo, when there were only a few rounds left in the mag. Not sure if that was on account of pistol weight, or magazine spring pressure with less rounds on board.

[YVK]

I've a massive contribution to this thread. I shot a whole of 15 rounds of 115 grain PMC that usually clocks at sub-130 power factor from 5 inch bbl. Glock 19, Radian comp, ACRO P2 mounted behind a BUIS through an adapter plate, support hand, and, of course, a factory recoil assembly. There is a brass plug in the grip. The ejection was predictably weak but no stoppages.

[Sero Sed Serio]

I ended up realizing that my Gen 4 22 was less reliable with hard cast ammo, when there were only a few rounds left in the mag. Not sure if that was on account of pistol weight, or magazine spring pressure with less rounds on board.

I suspect that Glocks still rely to a certain degree on the next round in the magazine to aid in extraction, with some variation between individual guns. My theory for my specific instance is that the reduction in magazine spring tension is the tipping scale when combined with all other factors (WHO, weak ammo, shooter fatigue, dirty gun, maybe hot gun).

[Bucky]

Help desk basics.

Q: My so and so doesn’t work on my Windows PC.
A: Did you reboot?

Q: My so and so supposed to be reliable 9mm is jamming?
A: Are you shooting factory 115s?

[matt7184]

I suspect that Glocks still rely to a certain degree on the next round in the magazine to aid in extraction, with some variation between individual guns. My theory for my specific instance is that the reduction in magazine spring tension is the tipping scale when combined with all other factors (WHO, weak ammo, shooter fatigue, dirty gun, maybe hot gun).

They do.

https://pistol-forum.com/showthread....thout-Magazine

[1Rangemaster]

First, I appreciate @GJM and is field contributions, to include his highly competent wife and her efforts.
I've been following this thread for a bit, and although it's mentioned, I just wanted to put forth some ammo specifics.
The Glock, as many martial pistols are, is typically tested with what we know n the US would think of as +P ammo-124 gr. fmj @1200fps. @GJM mentioned it earlier that he had settled on G9 solid 124 gr. copper ammo. According to their site it clocks @1200fps. So, one has to start with the fuel so to speak. If the ammo is "weaker" that begins to setup the problem. I do know also one can go the other way too. Too much pressure/velocity and the upper can outrun the mag spring.
I'm an admitted drill/eval nerd, and shoot a fair amount support hand only. I have not had a stoppage shooting thusly, but we usually run ball ammo. The gun(sample of one) is a GEN5 19MOS with an ACRO- now a P2 and usually a TLR8g mounted. For me it's worked, and has worked for others. I think @YVK might be into something with the weight/resistance of the shooting arm.
Just my$.02. Change factors and things might change.
The other wise comment from @GJM was an N frame would be good in terms of support hand reliability. And the one gets into revolvers and debris, etc.
Others mileage may vary; I'm going to work on support hand shooting and will report if anything stops.

[PD Sgt.]

Also thanking GJM and all of his contributions, I am wondering if, as another possible test, using a P2 on a 47 slide and 19 lower would help to determine anything. You would have the increased mass of the larger slide still using the 19 RSA, coupled with the smaller frame. It would take the delaying action of the comp out of the equation.

Having said that, I plan on hopefully able to test my own 47/19/P2 set up in the next few days. I have been carrying a G5 19 with a MPS and a Mayhem/PM single port comp for some time with no adverse function, though I am reasonably fit and 6’3” and 225, so I have a fair amount of mass behind the pistol (I would like about 10 pounds less, but that is another thread). Most of my practice is with 147 WinClean, as that is what is provided by work. S&B 124 grain has also run without issue.

If I can get everything together this week I will purposely try to duplicate a compromised grip and see how it performs to report back.

[PD Sgt.]

Well, I had a chance to take the 19/47/P2 out this week. The pistol itself has a Glock performance trigger, and an aluminum CHWPS grip plug. Other than that it is stock.

After zeroing, I put about 150 rounds through it with zero issues. Ammo was 147 grain Win Clean with 50 of 124g S&B. I alternated freestyle, strong and support hand grips, as well as as loose of a one hand grip as I felt I could safely accomplish, holding loosely with just my middle finger and thumb on the grip. Not one issue with cycling, whether a full mag or last round. So for a sample size of one, the increased mass of the 47 slide with a P2 on a FCS plate and stock G19 RSA did not show any adverse effects with reliability.

[TCinVA]

Cowan released a video on youtube covering the RMR HD. He states that Trijicon warns against mounting the optic on any gun where the optic overhangs the ejection port and in the video he shows multiple examples of the phenomenon in discussion. Worthy of note, Cowan is a lefty and his left thumb ends up sitting right at the back of the ejection port...which is most certainly a contributing factor on some pistols for some hands. I've watched thumbs bounce shell casings back into the ejection port on a number of occasions, especially on larger dudes shooting smaller guns with the left hand. (The P365 is really vulnerable) I coach people on this all the time in class and encourage either getting the thumb up very high or cranking it down to clear the ejection port:







He always shoots lefty but doesn't always experience this particular problem. It takes the addition of having a big optic mounted on the gun (admittedly with some overhang in this instance) to reliably produce the phenomenon. In several of the shots he captures on video you can see the occasional shell ejecting violently forward after being hit by the optic.

Best I can tell, he's shooting typical 9mm bulk ammo in the video and the ejection isn't great to start with. Shells sort of dribble out of the gun barely clearing his hands before they start to fall.

It makes a good argument for having irons in front of the optic, setting the optic back further on the slide where there is less opportunity to Mackenroe spent shells into the feedway.

[JCN]

Cowan released a video on youtube covering the RMR HD. He states that Trijicon warns against mounting the optic on any gun where the optic overhangs the ejection port and in the video he shows multiple examples of the phenomenon in discussion. Worthy of note, Cowan is a lefty and his left thumb ends up sitting right at the back of the ejection port...which is most certainly a contributing factor on some pistols for some hands. I've watched thumbs bounce shell casings back into the ejection port on a number of occasions, especially on larger dudes shooting smaller guns with the left hand. (The P365 is really vulnerable) I coach people on this all the time in class and encourage either getting the thumb up very high or cranking it down to clear the ejection port:

Best I can tell, he's shooting typical 9mm bulk ammo in the video and the ejection isn't great to start with. Shells sort of dribble out of the gun barely clearing his hands before they start to fall.

It makes a good argument for having irons in front of the optic, setting the optic back further on the slide where there is less opportunity to Mackenroe spent shells into the feedway.

Excellent assessment.

Compensator is also probably contributing to weak ejection too.

I know it’s not sexy, but if I had to run a gun with an overhanging optic I would consider a little black silicone caulk to fill the space under the hood to reduce trapping.