Unpleasing Gap Under Holosun 407

[GlockenSpiel]

So this is a direct-milled Glock RMR slide and a new 407. There is a gap both around the recoil lugs, and behind the screws. Total points of contact are lugs to optic at the front, optic to slide around the screws, and back end of the optic to slide. Optic did not feel wobbly when first putting on so I think the recoil lug fit is pretty tight. I see some chatter online about the lug holes in the holosuns not being deep enough.

I am reluctant to file the lugs on the slide as it is a hard to get factory rmr gun, and it's clear the optic is not 100% flat on the bottom anyway due to the various bits not being flush. Gun came with a milled steel plate cover that fit well, so I do not think there is a problem with the optic pocket. Is this concerning enough to not try this optic setup, is it a return to holosun, etc.?

[JCN]

So this is a direct-milled Glock RMR slide and a new 407. There is a gap both around the recoil lugs, and behind the screws. Total points of contact are lugs to optic at the front, optic to slide around the screws, and back end of the optic to slide. Optic did not feel wobbly when first putting on so I think the recoil lug fit is pretty tight. I see some chatter online about the lug holes in the holosuns not being deep enough.

I am reluctant to file the lugs on the slide as it is a hard to get factory rmr gun, and it's clear the optic is not 100% flat on the bottom anyway due to the various bits not being flush. Gun came with a milled steel plate cover that fit well, so I do not think there is a problem with the optic pocket. Is this concerning enough to not try this optic setup, is it a return to holosun, etc.?

Your screws may be too long and bottoming out. Take optic off and hand fit the screws with optic off.

It may require filing them down a thread but that doesn’t look clamped down enough to run. It’s traditionally optic screws that are too long. I often have to shorten Holosun screws depending on the application.

[Sig_Fiend]

Another potential option. What about trying an RMR sealing plate as a shim? Maybe that could help close the gap?

[GJM]

What is up with the gap in front of the optic?

[GlockenSpiel]

I wish it were the screws, but I don't think it is in this case. The optic came with long and short screws; the long almost fit but impinged on the extractor plunger on the right side. I put in the short ones instead, and since they're a fair bit shorter I don't think an excess of length is the issue.

I ordered a trijicon rmr seal plate to try and shim it. I'd rather have support/friction between more of the optic and not just the screws and lugs.

The front gap is just how the factory mos rmr guns are; they have a pretty ample optic pocket. It looks aesthetic af when the well machined cover plate is on it though.

[EVP]

So this is a direct-milled Glock RMR slide and a new 407.

If this is a direct milled for a RMR why is there so much room before and after the optic? Have you measured the optic cut?

I guess I am not following on the specifics given.

[JCN]

I wish it were the screws, but I don't think it is in this case. The optic came with long and short screws; the long almost fit but impinged on the extractor plunger on the right side. I put in the short ones instead, and since they're a fair bit shorter I don't think an excess of length is the issue.

I ordered a trijicon rmr seal plate to try and shim it. I'd rather have support/friction between more of the optic and not just the screws and lugs.

The front gap is just how the factory mos rmr guns are; they have a pretty ample optic pocket. It looks aesthetic af when the well machined cover plate is on it though.

Don’t just think or assume. Test it.

(P.S. I’ve had the short screws still be too long for some applications).

That optic isn’t snugged down. Either the bosses are too tall for the Holosun or it’s not being pulled down enough.

A shim would be a good idea but you want to make you know where all the tolerance stacking is. Because otherwise it will fail. PMOs are unforgiving of any hotspots.

[GJM]

I wish it were the screws, but I don't think it is in this case. The optic came with long and short screws; the long almost fit but impinged on the extractor plunger on the right side. I put in the short ones instead, and since they're a fair bit shorter I don't think an excess of length is the issue.

I ordered a trijicon rmr seal plate to try and shim it. I'd rather have support/friction between more of the optic and not just the screws and lugs.

The front gap is just how the factory mos rmr guns are; they have a pretty ample optic pocket. It looks aesthetic af when the well machined cover plate is on it though.

Just to make sure, you are not screwing the optic directly to the slide of a "MOS" slide without using an adapter plate?

[GlockenSpiel]

Just to make sure, you are not screwing the optic directly to the slide of a "MOS" slide without using an adapter plate?

It is a factory RMR footprint gun, so one of the numbered MOS patterns (I think rmr is mos 2?), not the normal MOS with plates. I have one of those too.

[Spartan1980]

To me it looks like the "male boss" of the slide isn't penetrating the "female boss" (hole) of the optic.

There's no way that optic is going to stay on that slide and hold zero. It's just not going to happen in that mounting with no front/rear support of the optic by the slide and no apparent recoil lug engagement either.