[lrrifleman]

Greetings!

This past weekend, I won a Holosun 509T. I plan on using it to replace the Vortex Viper on my 17.5 MOS. When I started to mount it with the provided Glock plate, a slightly long screw bent the Glock adapter plate like a piece of pasta.

Looking for a more durable plate that allows co-witnessing of the optic with the suppressor height irons, and I've narrowed my choice to one of two mounting plates: the Holosun 509 MOS plate versus the CHPWS V4 MOS plate.

Does anyone have experience with either plate? Would either plate be considered flimsy during normal use? Can the optic and suppressor height sights be co-witnessed?

As always, thanks in advance for your help!

 

[Rich_J]

The 509T is an RMR cut, right?

I have two Forward Controls plates in use with a pair of HS 507c’s: Glock 19 MOS and Glock 34 MOS. Probably 2,750 rounds combined, Zero issues.

Nitrided steel, not MIM. Fit is tight and tolerance is close. I really like the fences FC puts on the plate to hold the optic. Screws are included in tiny bags labeled with torque values.

 

[badandy2021]

I recently replaced the stock MOS plate on my G17.5 with one of the CHPWS V4 plates. I'd seen in other forums where people had had issues with them, but I think that was a past-issue with some models of their plates missing some important QC, but not mine; it just works. I use it with a Holosun 507C V2. The fitting is perfect, and the locking system they use will help to not repeat the same issue of a bent plate when using an out-of-spec screw. All their screws are labeled and packaged nicely as well. Pricey, but a good option if you want to stick to a specific model of RD, and the cool thing with holosuns is it lets you move up to the RMR eventually if you so choose, since they use the exact same footprint.

 

[lrrifleman]

The 509T is an RMR cut, right?

Honestly , I don't know. All that I can say is that the 509T clamps onto a dovetailed base. I am more familiar with iron sights than optics.

 

[GH34]

I have a Forward Controls plate for an RMR on my 17.5 MOS. I have a few hundred rounds through it with no issues. It has very tight tolerances and is made specifically for the optic. There is no awkward gap on the front or rear end of the optic. It looks very professional and is built like a tank. The mounting plate comes with all necessary mounting hardware to install it on to the MOS platform.

 

[MacMilly]

509 does not use rmr footprint. Forward controls is a good brand. I use them.

 

[BamaTrooper]

… and the cool thing with holosuns is it lets you move up to the RMR eventually if you so choose, since they use the exact same footprint.

The cool thing about the RMR is you can move up to Holosun if you want.

 

[cowboy1964]

The cool thing about the RMR is you can move up to Holosun if you want.

If someone offered me a free RMR or Holosun I'd take the RMR every time.

 

[BamaTrooper]

If someone offered me a free RMR or Holosun I'd take the RMR every time.

I have both. Granted we I’ve only had them about two years but I haven’t seen that much to make me spend the extra money They do have bigger drain holes though.

 

[sharpshooter]

If someone offered me a free RMR or Holosun I'd take the RMR every time.

I dunno... I have a RMR w/chpws v4 plate, it's reputation is undeniable. I also have the new Holosun SCS and I think the SCS may prove to be superior. You heard it here first. Time will tell, but the RMR is outdated and the SCS is pretty neat.

 

[C_Decker_68]

The chpws plate is very durable and would be a better choice in my opinion. Ameriglo xl size sights will give u a very low co witness using the chpws plate with your 509t. If you want a little more sight in the window for whatever reason, go with 2xl size sights.

 

[P89DC]

It's a fricking plate, how do you bend it and blame the plate? And then decide a $80 replacement is the solution? I'm sure Glock would send you a new plate for nothing. Then take your time and follow instructions....

 

[FireMedic-50]

C&H Precision Weapons (chpws.com)

Sadly the factory plates lack....

C&H plates are the way to go

 

[Rich_J]

Honestly , I don't know. All that I can say is that the 509T clamps onto a dovetailed base. I am more familiar with iron sights than optics.

Sorry, I think I misled you. I had to go look up the footprint of the 509T. Apparently it is it's own unique design, using a cross-slot and a locking lever. Looks like the FC RMR plate will not work. and you'd need a different solution than one of the four Glock MOS plates.

Holosun 509T Footprint - Optics Trade Blog

Holosun 509T features a unique mounting standard. Here, you can see the dimensions and the photo of its footprint.

www.optics-trade.eu

I see CHPWS mentioned. I had a dissappointing experience with their products, but sample of one and all that. They recently announced some improvements in their QC process so hopefully things are better. They advertise a 509T plate for the MOS. Given your situation, I'd probably go that route.

V4 MIL/LEO Adapter Holosun 509T Fits GLOCK MOS - C&H Precision Weapons

Holosun 509T Adapter Plate for Glock MOS | CHPWS GLOCK MOS adapter plate is the most rugged, reliable, and trusted red dot adapter plate on the market today.

chpws.com

Regarding BUIS, I'd pick sights which just cleared the deck height of the mounted optic. Ameriglo steel are ones I like, they offer sight sets in various heights that preserve POI = POA, for me at least.

As an example, I use a GL-470 set on my Glock 19 + HS 507c + FC Plate. This set is a 0.350" front and 0.429" rear. I use a shoot the dot hold.

GL-470 | AMERIGLO.com

Your default description here

ameriglo.com

The sight picture has the front in the notch maybe 30% into the optic window. It's there, and usable, but out of the way, generally.

 

[Gman3101]

Uses the wrong screw to mount the optic, complains when the plate bends.

 

[P89DC]

C&H Precision Weapons (chpws.com)

Sadly the factory plates lack....

C&H plates are the way to go

Lack what? I'm genuinely confused, please edjewmakate me.

 

[Rich_J]

Lack what? I'm genuinely confused, please edjewmakate me.

Factory MOS plates are MIM. Installed on a pistol MRDS, and combined with irregularities in the MOS factory cut, or material deposited as part of the coating process, it can lead to additional stress on the plate, as it rocks back and forth. That stress can manifest itself more in high round count, high usage training classes. The result is cracked plates (bad) or optics which fly off in use (worse).

For that reason, many opt for aftermarket plates which are more robust (aluminum, steel), milled more accurately (i.e. flatter to a tighter tolerance), or have features the OEM plates lack (recoil fences, in the case of the Forward Control plates). Some also use a "gap filler" such as E6000 under the plate but I am not sure this would be something I'd do under normal circumstances. Those using it report good results, but as they say, absence of evidence is not evidence of absence.

Personally I have not seen these issues since I opted to use FC plates from the get go. Other high volume trainers such as Aaron Cowan do cite problems with the Glock MOS plates specifically, reporting their observations in their training classes.

 

[lrrifleman]

It sounds like I have to defend my actions.

I had installed a Vortex Viper about a year or so ago using the included plate system. Because I was unable to co-witness the factory sights with the Vortex optic, I installed a set of AmeriGlo suppressor height sights. With that combination I could co-witness.

Last weekend, I won the Holosun. I read the installation instructions and started to install the plates. Just stacking the Holosun on top of the Holosun base AND the Glock plate, the tops of the AmeriGlo sights were below the mounting deck of the Holosun and I was unable to co-witness the sights. FIRST reason leaning towards a specialty base. I presumed that the base screws would be sufficient to install the Holosun, I quickly found that I was wrong. Holosun sent out appropriate screws for mounting their base to the Glock plate, but due to the neuropathy in my hands, I didn't feel the screws bottom out and lift the Glock plate. Having bent the Glock plate was the SECOND indicator that I should invest in a specialty base.

Utilizing 50+ years of experience shooting in competitions with mission purpose rifles and pistols, I know not to take the cheap solution. I realize that I could have replaced the Glock MOS plate and installed the Holosun, but that avenue denied me the ability to co-witness my sights, which I feel that I must do until I become more accustomed to using a red dot style optic. Wanting to mount the optic while retaining the ability to co-witness the sights is what prompted my durability question, not that I bent what amounts to a $6 piece of MIM metal.

I opted to purchase the CHPWS plate for my Glock over the Holosun plate not because it was more expensive, but while I could find the Holosun plate for 2/3s the price, it was difficult to get information on the base from the Holosun website. For me, that was a warning flag that there may be some issues with it.

At the moment, it seems that I am having a higher degree of success in using this optic with both eyes open, which could lead to success transitioning to an MOS unit. I am hopeful.

 

[musicman10_1]

It's a fricking plate, how do you bend it and blame the plate? And then decide a $80 replacement is the solution? I'm sure Glock would send you a new plate for nothing. Then take your time and follow instructions....

Do you know how I know you have never worked with one of the JUNK plates that Glock provides with the MOS?

Forward Controls Design is what I bought and my RMR rides like a rodeo champ on it.

 

[P89DC]

Do you know how I know you have never worked with one of the JUNK plates that Glock provides with the MOS?

Forward Controls Design is what I bought and my RMR rides like a rodeo champ on it.

Umm, okay. What are these, chopped liver? Lol, gen 5 34 MOS and gen 5 45 MOS. Mounted with included hardware and a couple drops of purple Loctite. I didn't appreciate the screw length first pass but I noticed the issue immediately and figured it out.