Glock 19 MOS vs Milled stock G19

#21
It's an issue with universal cuts for optics. It is not an issue for slides milled for a specific type of optic, when they're done well enough to support the optic properly.

Out of curiosity so I can understand your failure better, did the screws actually break off in the plate holes, or did they strip the threa
The plate screws actually broke off in the slide holes just slightly below top surface area. The screws showed no indication of being loose and i had been checking the optic from time to time to make sure everything was secure.

I'm not upset or mad, stuff breaks, i just found it interesting and reviewing the damage thought this might be a problem that afflicts univeral optic mounts in general.
 

user12358

Regular Member
#23
I'll chime in with some of my experiences, especially with a Gen 5 MOS. Trijicon now makes a $16 kit that solves the issues that plagued the RMR on a MOS slide initially. With the new screws I haven't been able to find any problems of screws backing out or sights going airborne after around 1000 rounds of +P 9x19 on a Gen 5 17 MOS, not an endurance test by any means but so far it is holding up as it should have in the beginning. However, the MOS system has the RMR riding much higher on the slide than a dedicated mill job. This isn't the end of the world but it is certainly nicer to have the optic lower like milled slides do.

I specifically bought a Gen 5 17 MOS because now I don't have to send it out for front serrations like the Gen 4 MOS and it will be ready to immediately accept an Aimpoint ACRO when it comes out along with any other future optics that are released. For serious use guns I will still always be getting a dedicated mill job because you are only losing flexibility and incurring some extra cost to get a more robust and in most cases lower mount with one less failure or movement point. That being said, I would still have confidence in using the MOS system if it was issued to me and I was unable to use a dedicated mill job slide.
Just to update this because I only had a thousand rounds on the gun at time of posting. I ended up running the Gen 5 17 MOS mentioned in the post up to 9,243 rounds using it as a practice gun as of today. The only problem I have run into of the course of the running the RMR on the MOS plate with the Trijicon kit is the RMR started to come loose at 1215 rounds. I noticed this because of a group shift of 6 inches to the right at 25 yards to which I re-torqued the screws to the old German torque spec of "Gutentite." The optic has not come loose since being fed a diet of exclusively NATO spec 9x19.

It should be noted that I did not use any form of thread locker on either the plate screw as the RMR was supposed to be changed out "any day now" for an Aimpoint ACRO and this has exclusively been a practice gun. It has held on for over 8,000 more round with no thread locker as more of a morbid curiosity test than anything else. I would not recommend not using thread locker on a duty or defense gun and will probably be changing to a C&H V3 plate the next time the optic comes loose. That being said, the MOS system has far outperformed my expectations for a factory modular optics system and I do believe it to be serviceable.
 
#24
Can anyone confirm the 1/3 co-witness sight height for an RMR/Holosun on an MOS slide with a CHPWS plate? I'm finding all types of answers. Bonus points if you can tell me the Ameriglo part number for an all-black set of the right height.
 

user12358

Regular Member
#25
Can anyone confirm the 1/3 co-witness sight height for an RMR/Holosun on an MOS slide with a CHPWS plate? I'm finding all types of answers. Bonus points if you can tell me the Ameriglo part number for an all-black set of the right height.
The CHPWS V3 plate is, near as makes no difference, the same height as the standard MOS plate and the only difference in height comes from not having to use the Trijicon MOS kit with the sealing plate. I am using Ameriglo GL-429 sights to provide a barely there BUIS solution. This is as barely there as is gets and a little less than half rear notch is blocked by the RMR body but is still enough to equal height/equal light if needed. If you are looking for a true lower 1/3 your would probably need to step up to their MOS height but I have no experience with those sights.
 
#26
The CHPWS V3 plate is, near as makes no difference, the same height as the standard MOS plate and the only difference in height comes from not having to use the Trijicon MOS kit with the sealing plate. I am using Ameriglo GL-429 sights to provide a barely there BUIS solution. This is as barely there as is gets and a little less than half rear notch is blocked by the RMR body but is still enough to equal height/equal light if needed. If you are looking for a true lower 1/3 your would probably need to step up to their MOS height but I have no experience with those sights.
PM sent.
 
#27
The CHPWS V3 plate is, near as makes no difference, the same height as the standard MOS plate and the only difference in height comes from not having to use the Trijicon MOS kit with the sealing plate. I am using Ameriglo GL-429 sights to provide a barely there BUIS solution. This is as barely there as is gets and a little less than half rear notch is blocked by the RMR body but is still enough to equal height/equal light if needed. If you are looking for a true lower 1/3 your would probably need to step up to their MOS height but I have no experience with those sights.
Just want to add that the G17MOS, CHPWS plate, GL-429, and the Holosun give the same BUIS sight picture. It's pretty low (probably lower than 1/3 co-witness), but looks perfect to me. I can easily pick up the irons, especially if the weapon-light is on, but it doesn't "busy-up" the glass when the dot is on.
 
#29
What I’m getting from this is, I should send my slide off to be milled if I want a dot on my gun instead of buying a mos. am i off?
I've gone both routes several times. As already stated repeatedly, the Factory MOS plates are less than ideal. However, in using the MOS cut slides, I have added a CHPWS RMR plate to a G34 Gen5 & and a Forward Control Design RMR plate to a G17 Gen5 that have worked exceptionally well so far. I have around 5K rounds on the CHPWS & 1200 on the FCD, with no optics related issues to this point.

You'd also be good to go with sending a non-MOS slide to a reputable company for an RMR cut. I've been very happy with the work from ATEI & Landers Weapons Systems.
 
#31
I have both, and from my experience the durability from an upgraded MOS plate from CHPWS or FCD against a milled gun has been the exact same. If you want the best solution possible IMO a pro cut from ATEi is still the gold standard but I have yet to have an MOS mounted red dot (Deltapoint Pro, RMR, SRO & Holosun) fail because of the mounting platform.