I recently installed a 509t on my MOS Glock. I used a C&H mount. Followed their directions on the mount(torqued to 11in/lbs instead of 10)
I placed the optic on the mount and torqued to 15 in/lbs. I let everything dry for 48 hours. After 200 rounds, the optic screw loosened up. I removed the optic (the mount didn’t move) Degreased and applied more blue loctite. After another 200 rounds, it seems good to go.
For those that are running a similar setup, what are you torquing to?
Thanks!
Hardly scientific, but I torque as much as I think I can without stripping the screw. Just confirmed -- the 509T I put on the Gen 5 20 10mm hasn't moved.
Likes pretty much everything in every caliber.
About to install my first RDS… Aside from stripping the screw, is there any downside to overtorquing?Originally Posted by GJM
You are not the first one to have issues with aluminum plates--especially with cross-bolt mounted optics like the 509. Did CHWPS really spec 10 in-lb for the cross-bolt? Or was that for the mounting screws?
I strongly prefer steel plates. Holosun makes a steel MOS plate.
Holosun spec for the clamp screw is 20 in-lbs. I use 25.
I would worry about damage to the optic if you severely exceeded the torque spec.
“There is no growth in the comfort zone.”--Jocko Willink
"You can never have too many knives." --Joe Ambercrombie
Well… in one video, they say 10 in/lbs for the crossbolt. In another video, 15 in/lbs.
I shot another 200 rds today and had no issues. Hopefully it holds up over time. This gun will be used a lot and carried daily.
I almost went with the holosun mount, but read a lot of negatives. Is that what you run? Any issues with it?
It’s cheap enough, I might just order one for a backup.
No issues with my Holosun RMR footprint mount after over 5k rounds. What/where have you read about issues?
I'm really surprised by the 10 in/lbs torque spec, and not in a good way.
@SoCalDep, any thoughts?
“There is no growth in the comfort zone.”--Jocko Willink
"You can never have too many knives." --Joe Ambercrombie
Don’t use aluminum plates for cross bolt mounts if it can be avoided.
Buy the OEM Holosun 509t steel MOS adapter plate.
https://holosun.com/index/product/detail/id/193.html
I strip the factory threadlocker with acetone and use loctite 248 (blue oil resistant chapstick).
Torque the plate to 15 inch pounds, torque the cross bolt to 20 inch pounds (all per holosun’s suggested torque)
I do 12in/lbs plate-slide and 15in/lbs optic to plate. I too prefer steel for clamping-type optics but never had a problem with my C&H plate with a Glock. We did have issues with M&P plates but they seem much improved now. I do see that C&H now lists some steel options for 509T plates but the Glock one is out of stock.
I think the second mount job is good to go. It didn’t loosen up at all. There was probably some oil I missed the first time around. I am probably going to order the Holosun mount as a backup JIC.
20 in/lb with blue loctite. Hasn’t loosened in almost 4,000 rounds of 9mm
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