Any flat screw head of appropriate diameter thread will work just fine.Originally Posted by Clusterfrack
I bought a whole tray in different lengths, metric and standard because going back and forth from Holosun and Trijicon requires different heads.
Also, some SRO mounts with posts require M3 or M4 flat heads.
Do you have a link to that tray?
“There is no growth in the comfort zone.”--Jocko Willink
"You can never have too many knives." --Joe Ambercrombie
I need some 6-32 by 9/16" long. I found these two:
McMaster-Carr
Fastenere
They both have allen heads. I prefer T15 torx but could not find any. Does anyone have a source for what I am looking for?
G19.5 MOS
Holosun 507c
CHPWS GL-RSH V4 (RMR/SRO/407c/507c/508t)
* Replacement screw kit for GL-RSH
CHPWS is out of the replacement screw kits I need, and didn't respond to service requests (voice, email). Ordering screws from McMaster.
Plate-to-slide:
* As earlier in thread: Zinc-plated alloy steel M3 x 0.5 mm Thread Size, 6 mm long
Holosun-to-plate :
* Black oxide alloy steel 4-40 x 1/4 in long
Should these sizes work for the screws?
Ideas on where to get replacement T-nuts, since CHPWS is out of kits and not responding?
Last edited by maximus83; 01-09-2023 at 03:58 PM.
I looked at the plate-to-slide screws you linked and they show “not rated” for tensile strength and sourced from numerous countries. I prefer the alloy steel screws made in the USA and rated at 140,000 psi tensile strength. They are item number 94414A712 from McMaster.
As for the CHPWS compatible screws, I have the 4-40 x 1/4” with torx drive for Holosun - CHPWS plate, which is item number 94414A106. The screws for RMR - CHPWS plate (4-40 x 5/16”) are item 94414A322.
I also ordered some 4-40 x 3/8” screws (item 94414A108) and I can’t remember exactly why, but Langdon Tactical for their 92 series mill/plate, Agency Arms, and CHPWS use 4-40 screws. It probably had to do with one of those.
I won’t trust what is “listed”, and I’ll test fit the optic to the plate to see how deep the screw sits in the T-nut and/or plate and may go with either/any of the recommended lengths based on how it fits.
To be honest... With a Glock MOS unless you bent the factory plate by using the wrong screws or massive abuse in shipment or handling, if mounted right I prefer it to CHPWS. I prefer the Forward Controls Design (If available for your optic) to either.
I have no idea where to get T-nuts besides CHPWS, but I have a few sets so if you PM me your address I’ll send you a set.
@SoCalDep thanks, great info not easily obtainable anywhere else.
Based on your comments:
* I have an FCD plate on my G45 for my SRO, love it. Could I use an FCD for my Holosun 507c? Their website suggests the 507c will work with their plate, *if* you use the shorter screws.
* Interesting you prefer the OEM MOS plates to CHPWS. I think if I'd know that I wouldn't have bothered with the CHPWS.
FCD says maybe (you can use a Holosun) but last I saw they won’t specifically list it as compatible. I’ve installed a couple Holosuns and they worked - but it’s a “YMMV” thing. You do need to use shorter screws, and that’s another issue because the Holosun 507C needs a thinner head compared to the RMR as well as being shorter (5/16” vs 3/8”). For the Holosun - MOS (which would be the same as a FCD plate) I use the zinc-coated steel screws from McMaster or the shorter screws included with the Holosun (test fit with the optic in the plate before installation to make sure they don’t protrude, which will bend the plate). The McMaster screw item number is 90920A274, which is for the 6-32 x 5/16”.
As for the MOS vs CHPWS, I think the company is being super responsive to the industry and I’m happy for that. They have been very responsive to fix some issues my department had, and they are, more than anyone else, trying to make as many optics fit on as many pistols as possible. So... I like CHPWS. They have their issues because they were a small company that got big maybe faster than they were prepared for.
The reason I’m a fan (right now) of the MOS over the CHPWS is because I feel that when mounted properly, a 6-32 screw is stronger against torque and shear forces than a 4-40, and though C&H uses T-nuts that support the screws, the 4-40 torqued down against the optic can shear (I’ve sheared a few until I started using alloy steel screws) and I’ve seen as many issues with screws shearing off during firing with C&H as I’ve seen with MOS. Done right with the right length and enough but not too much threadlocker (NOT VC-3!!!!!!!) they do work very well.
I just think based on what I think I’ve learned that as long as there’s enough thread engagement, which isn’t all that much, it’s about not coming loose. An MOS has enough engagement and when mounted correctly won’t come loose. I actually spent my own money to have a few sets of C&H plates for our guys with M&Ps that show up to mount optics and didn’t realize they needed the plates from the factory box... but ultimately my favorite plate for Glocks is the FCD and it’s the same screw size and thread engagement as the MOS...
Just a quick note to mention that my recent experience buying a plate from FCD might very well be the absolute best service I have ever experienced for anything- much less stuff in the firearms space. If every company handled orders the way they did, there would never be a need for customer service representatives. Just amazing.
Also I really appreciate how they labeled the included screws with the exact specifications. The quality of the plate was just outstanding too.
What would be the McMaster Carr part number for screws to replace the OEM Sig Sauer screws to mount a Romeo 1 Pro to a factory optics-ready P320?
My posts only represent my personal opinion and do not necessarily reflect the opinions or official policies of any employer, past or present. Obvious spelling errors are likely the result of an iPhone keyboard.
I wish I could give you a good answer but I haven’t found any. I ended up ordering a set of screws from Sig just in case. The only P320ish pistol I have is an M17 and it’s a training/loaner gun with a DPP on it. I ordered the screws in case I have a student that needs a loose optic re-mounted. Thankfully Sig does a good job mounting their optics.
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