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Which screws for a P365 Optic Cover Plate?

Wolkenflieger

Wolkenflieger

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Howdy,

I'm looking for cover plate screws that would fit a factory optic-ready slide for a P365 standard, 3.1" barrel.

I've looked online already and am seeing conflicting information. Some are saying the optic plate screws should be M3 .05 thread pitch and 5mm long. Others are saying this is too small and that an M4 should be used for newer guns.

My P365 is off-roster purchased via PPT (so not brand new) and it has a Radian Ramjet/Afterburner on it.

The optic plate cover I'm looking at is the NDZ Performance plate cover from Amazon, since SIG is out of the stock of their stock cover plates. Any better optic cover plate suggestions are welcome, since the black NDZ plate doesn't seem like a perfect match on a black gun.

Anyone know exactly which screw size/pitch/length would work for a slide optic plate cover?

Thanks!
 
You might have good luck for a fastener shop near your location or an OG style hardware store like Ace Hardware if those are in your area
 
Does the CA version fit? If so I have 2 with hardware that will never go back on
 
My understanding is non sig-loc slides use m3. Sig-loc slides use m4. Sig-loc optics mount from underneath, so if your screw holes go all the way through the slide, then they will be m4.
 
lopez1171 said:
You might have good luck for a fastener shop near your location or an OG style hardware store like Ace Hardware if those are in your area
Click to expand...
I was just going to buy some metric screws from Amazon once I know which sizes to get, even if I have to buy both M3 and M4. The M3 size I found is M3 .05 thread pitch, 5mm length.

Not sure about the exact M4 spec but I had it up on Google not too long ago.
 
Wolkenflieger said:
You're talking about a SIG optic cover plate with screws? Would love to buy one from you if you think it'll fit a standard P365 slide. I'm not sure if yours will fit a CA model but I don't see why not.
Click to expand...
I have one from the CA 365 XMACRO comp and one from the 365 XL rose
 
Punkur67 said:
I have one from the CA 365 XMACRO comp and one from the 365 XL rose
Click to expand...

I'm thinking the XMACRO Comp plate and screws will work. Gonna Google really quick here. Here's the gun I have (no light). I want to take the optic off and install a plate there. Plate and screws are black I take it?

AI Result; "Yes, the SIG Sauer P365 XMACRO optic cover plate and its accompanying screws are compatible with standard P365, P365X, and P365XL slides"

Thanks!
1773630878451.webp
 
These are pictures of my slide from a PPT-purchased P365, so I don't know its history. The optic screws go in from the top and do not go all the way through. An optic plate cover would be much thinner than the 407k optic body so I don't assume the screws would be ideal for a plate.

Does that look like a stock recoil spring? I didn't see any lettering on it. Was hoping it would be a DPM but that wasn't advertised. Googled it, and it does look like it could be a stock recoil spring.

Also, this slide looks like it was cut aftermarket, or do stock SIG optic beds look like that? That looks like raw steel there, no coating. Not sure it was even blued. Looking online, the stock "optic ready" optic areas should have a nitride or similar coating matching the rest of the gun coating. I probably need to get this blued at least.

Thanks
 

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Wolkenflieger said:
These are pictures of my slide from a PPT P365, so I don't know it's history. Optic screws go in from the top and do not go all the way through. An optic plate cover would be much thinner than the 407k optic body so I don't assume the screws would be ideal for a plate.

Does that look like a stock recoil spring? I didn't see any lettering on it. Was hoping it would be a DPM but that wasn't advertised. Googled it, and it does look like it could be a stock recoil spring.

Also, this slide looks like it was cut aftermarket, or do stock SIG optic beds look like that?

Thanks
Click to expand...
That’s not Sig-loc. You would see screw holes on the underside. Like here:1773632902058.webp
Also, that is a custom cut. A factory optic plate likely won’t work. There has to be a notch for this tab to slide into. 1773633139496.webp
 
mcnaugcl said:
That’s not Sig-loc. You would see screw holes on the underside. Like here:View attachment 166005
Also, that is a custom cut. A factory optic plate likely won’t work. There has to be a notch for this tab to slide into. View attachment 166009
Click to expand...
Thank you, you've saved me some time and aggravation. Maybe I'll leave the optic on there, but I think I need to get that raw steel coated!

I wrote to Wager for help. They could coat the cut area and *maybe* make me a custom optic plate cover. I know their turnaround time is quick and their prices are reasonable.
 
Last edited:
Wolkenflieger said:
Howdy,

I'm looking for cover plate screws that would fit a factory optic-ready slide for a P365 standard, 3.1" barrel.

I've looked online already and am seeing conflicting information. Some are saying the optic plate screws should be M3 .05 thread pitch and 5mm long. Others are saying this is too small and that an M4 should be used for newer guns.

My P365 is off-roster purchased via PPT (so not brand new) and it has a Radian Ramjet/Afterburner on it.

The optic plate cover I'm looking at is the NDZ Performance plate cover from Amazon, since SIG is out of the stock of their stock cover plates. Any better optic cover plate suggestions are welcome, since the black NDZ plate doesn't seem like a perfect match on a black gun.

Anyone know exactly which screw size/pitch/length would work for a slide optic plate cover?

Thanks!
Click to expand...
Use the ones that fit.
Without knowing what size screw holes you actually have, there can be no 100% correct answer.
It's easy to determine 3mm vs 4mm screw holes.
3mm x 0.5 threaded holes will be 2.5mm diameter inside the threads while M4 threaded holes will be 3.3mm diameter inside the threads.
 
AR15barrels said:
Use the ones that fit.
Without knowing what size screw holes you actually have, there can be no 100% correct answer.
It's easy to determine 3mm vs 4mm screw holes.
3mm x 0.5 threaded holes will be 2.5mm diameter inside the threads while M4 threaded holes will be 3.3mm diameter inside the threads.
Click to expand...
Thanks. The cut looks custom so I probably can't install a cover plate. The diameter tip is helpful!

I'll probably need to put an optic back on on after getting the cut area protected somehow.
 
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