I wanted to caution everyone regarding the Scalarworks Beretta 1301 Sync Mount potentially damaging the shotgun receiver.

I recently attempted to attach a Scalarworks Sync Mount with a Trijicon RMR to my Beretta 1301. Per the instructions, I initially attached the optic to the mount separately from the shotgun to check for protrusion of the screws through the mount. The degree of protrusion appeared questionable so I contacted their customer support who sent me two new sets of screws for comparison.

Upon receipt of the new screws, they appeared to all be of equal length. Against, my better judgement, I proceeded with attaching the mount to the shotgun receiver followed by the optic. As it turns out, my concerns were correct. Even with the proper mounting screws, the level of protrusion through the mount is enough to damage the receiver.

Let this be a warning to anyone considering these mounts before they end up damaging their $1500+ shotgun.

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That is a tiny nick that is under the mount, it’s so tiny you couldn’t even hold the camera steady enough to capture it. Wait until you shoot it, it will get dirty too. It’ll be okay.

Shorten the screws with a file or sandpaper.  This is not a problem other than you scratched your  gun.


ETA - It happens.  Don't worry about it....   You'll know better next time.

File the end of the screws ... check.

You don’t really even need to do that. The reality is there is always going to be some tolerance variation at play. You have the spec of the receiver and tapped holes, the spec of the mount along with the spec of the screws that attach the mount to the receiver, the spec of the optic and the spec of the screws that attach the optic to the optic mount. You are going to see variables in some or all of these various parts. Metal to metal contact is going to happen and in this instance you have tool steel screws contacting an aluminum receiver, the tool steel screws are always going to win. If you shoot enough and even with everything torqued to spec, you will see some finish wear after you remove the mount, any mount from any manufacture. Under recoil there is vibration and movement that will cause wear eventually. The only way to mitigate that wear is to use the polymer pic rail and mount an optic to that.

I have used the GG&G RMR mount, the Scalar Works RMR mount and currently am using the Scalar Works Acro mount on my 1301s. All have been fine, the GG&G mount had soft screws that once were upgraded was fine. Scalar works makes excellent stuff. I have their sights and mounts on ARs, PCCs, and shotguns. All have been outstanding.

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I just looked up the instructions for the Scalarworks Sync mount. Step #1 is literally two pictures of the mount with screws. One below flush that says "Yes", the other sticking out that says "no".

You failed step #1. The Mount is fine.

I don't know how it could get any simpler.

Poor baby. Wait until you start running the gun and the receiver gets rashed up from port loading. Beware anyone using ammunition in their guns, it will make marks on the receiver.

You saw they protruded, so why did you mount it before using a file or sandpaper to shorten the screws?  

ETA:  And the directions couldn’t be any more clear.  

You cut out the important warning directly beneath that part.

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I don’t remember off the top of my head but I think I remember the RMR mount came with two sets of screws one for the RMR and a longer set for the Holosun optics. The longer Holosun screws will easily bottom out on the RMR. I also wonder if the OP used the rubber O-ring on the mount. Thing is about Scalarworks stuff is that they are packaged very well and everything this labeled. There are no generic baggies. Each individual part is packaged and labeled including the high quality torx bit they provide with every mount. The instructions like wise are very clear. This is a case of the OP not reading the instructions and or using the wrong screws in the package.

It's only a tiny nick because I backed off after feeling some resistance. It would have been much deeper had I torqued the screw down to the recommended specs.

I did read the instructions beforehand. However, because the bottom of the mount and top of the receiver is rounded, slight protrusion may not be entirely noticeable. The mount and optic appeared to sit flush when
placed on top of the receiver. I even contacted the manufacturer with my concerns before proceeding and couldn't get any additional clarification. They were kind enough to send me extra screws to at least verify that the screw length was in spec. Furthermore, why is this even an issue? Is it too much to expect manufacturers especially ones charging a premium to includes parts and hardware that are properly sized?

Gun owners must have some of the lowest standards when it comes to consumers despite spending $$$$. Whether its $1500 colt pythons having tooling marks in the barrel and hidden under the grip, $50 sig p365 magazines rusting from normal use, or $3k LMT rifles coming in with clear dings and scratches through the anodizing from what must be trainees assembling the rifles, it's a never ending wave of excuses on behalf of the manufacturers.

These screws were clearly marked for the Trijicon RMR and SRO. I even compared 3 different sets which were all equal in length and could only conclude that they were the proper length. The O-Rings are only intended for the mount to receiver screws, not the optic to mount screws.

These 1301s are mass produced. They aren't all unique with their own dimensions. Again, is it that hard for manufacturers to make parts that are properly sized with properly fitted hardware or is the standard now for consumers to have to measure and fit their own parts even after buying a supposedly premium product?

Shockingly, tolerances do exist.  You can get something called “tolerance stacking” when you get some parts together that may be at the opposite ends of allowable specs.  Increasing the amount of parts increases the chance tolerance stacking can happen.

You’re bolting Part A to Part B and then Part C gets bolted on top of it all (with all parts being from different manufacturers).  In the interest of making as low a profile mount as possible, likely to ensure sufficient cowitness with the 1301s low factory irons, Scalarworks elected to make those margins fairly small.  In doing so, they realized the possibility for screw/receiver interference and put a large warning in the instruction manual to test fitment before mounting so as not to damage your receiver.  Tolerance variations could be coming from any one of those parts, mind you (and the chances are low it’s with the simple machined piece of aluminum from Scalarworks).  Nevertheless, they put the warning in there to help you avoid this situation.

Now, you did accomplish that step, realized there was an interference issue, and contacted the manufacturer.  They sent you some new screws, which you tested and found to not correct the issue.

A logical person, at this point, would modify the cheapest part (the screws, in this instance), fix the problem, and go on their merry way.

You, on the other hand, having discovered an interference issue and realizing the new screws had not fixed the issue……decided to try mounting it anyway.  Predictable results followed.

Dude, not everything is an AR-15.  Step outside of the AR world and it’s not terribly uncommon to need to “fit” parts to one extent or another when working on guns.  If you’re not willing to accept that, maybe it best you leave any firearm modifications to a qualified gunsmith.

Yes, it is that hard. The standard always was, and will for a long time continue to be that you need to check your screws. Is it really so hard to expect someone smart enough to use firearms to fit some screws, especially when it's step #1 with pictures a 6 year old could understand?

If the bold part were true, you wouldn’t have tried to mount it using the SRO screws with an RMR..

Yes, I realize that, that still doesn’t answer the question, did you install the o-rings or not?

You can’t be serious. You realize mass production is exactly the reason there are variations in tolerances between parts. There is a specification set by the manufacture of what variance in tolerances are allowed and these variances can be + or - a set dimension. The fact that you don’t understand this and yet you want to start cranking parts down on a gun is pretty crazy to me. You should let a gun smith work on your gun from here on out IMO.

No issues with mine.

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So let me get this straight… you knew the screws were long and protruded, they sent you out another set that was the same length. You installed them anyway and fucked up your receiver and it’s somehow their fault. LOL

Your lack of ability and know how fucked your gun up. If you had a clue what you were doing you would have just shortened the first set of screws to the proper length.