I have a Romeo 4m and a Romeo 5. I've installed them and shot a couple 100 rounds through each rifle, and had no issues with the optics. I swapped the Romeo 5 from my AR Pistol to my MPX without issue. the Romeo 4, I swapped from my AR15 to my AR Pistol once, and then back again. When moving it from the pistol the rifle, I unscrewed the hex key, and the sight fell off after one turn of the screw. It had broken in half right where the threads start.

Since the 4M came with two mounts, I grabbed the other screw and mounting piece from the other mount and re-attached it to my rifle. I have a friend who may buy the rifle from me, so I went to remove the optic today and the second screw did the same damn thing.

i don't think I over-torqued the screw by any means, and it held firm until I tried to remove it, so I don't know when it sheered or what's holding the sight on the gun.

I was going to pass the first one off as a fluke, and haven't gotten around to calling Sig about it, but now that both of the screws have failed, I'm a bit more concerned.

has anyone else run into this issue? Am I doing something wrong?

Doesn't look like a quality screw to me.....just a amateur's opinion....

quote:

Originally posted by mike28w:
Doesn't look like a quality screw to me.....just a amateur's opinion....

Yep. I'll go a step further and say that it looks cast, which isn't ideal for a part that's going to be subject to both shock and torque stress at the same time. Not only torque when mounting on a gun, but also when tapping the thread.

Interesting to see that it broke where the bolt exits the channel it rides in. It's possible that if the mount isn't torqued enough, the sight could have enough longitudinal movement under recoil to stress the bolt until it flexes in the unsupported area then shears apart.

That said, does the owners manual have a torque spec for the bolt? I used to do the "tighten down till it feels snug" approach, but now love my torque wrench.

That’s the very reason I ditched my bushnell trs-25. I was able to replace the screw with one from the Home Depot, but I just couldn’t shake the thought that if they cheaped out on the mounting hardware, it was only a matter of time until I discovered where else they saved money.

However, you could take the threaded piece to Home Depot or Lowe’s, and screw it onto that thread measuring device they have in the hardware aisle, and be in business.

Screw was probably "Hecho En China".

quote:

Originally posted by JJexp:
However, you could take the threaded piece to Home Depot or Lowe’s, and screw it onto that thread measuring device they have in the hardware aisle, and be in business.

One could certainly try to find a replacement at a hardware store, but I wouldn’t bet on it. There’s more to finding replacements for screws like that than getting the proper thread pattern. For example, try finding an exact replacement for a P226 grip screw at a store. The one pictured has a very long unthreaded shank with respect to the threaded portion, and I don’t believe I’ve ever seen something like that in the bins at Lowe’s. The screw head dimensions and length of the screw may also be unique to that mount.

Id call sig, get 2 replacement screws, sell them as quickly as possibly, replace with a quality mount, hope the sights dont suffer the same. My Romeo 4 has been running flawlessly since day 1.

I had to turn right around and go back to the store to return my newly purchased Romeo5.

One of the four screws which secure the optic to the included mount was sticking out half-way, and at a weird angle. The threads were completely stripped out, rendering the thing pretty much worthless.

It came from a factory sealed box. Those clowns in China had to have known that it was jacked-up when they boxed it up.

The dealer didn't have anymore in stock, except for the display model (I just loooove smeared lenses). It has so far not broken, yet. However, I will always know that it is nothing more than a overpriced piece of chicom shit with a Sig label on it.

They take an Aimpoint compatible T-1 mount.
Switch to a better mount & one that's QD.



* Just my .02¢ - but if it'd only happened once I'd say it's the part. The fact it's happened twice to the same person !?!
I'd have to say there's a good chance that they were over tightened.

It’s not possible that the parts were made by the same manufacturer about the same time and were inherently defective?

I still have an extra P239 slide catch lever or two in my spares box because shortly after the pistol was introduced there was a rash of reports about the parts breaking in normal use. Those reports didn’t continue very long, and I’ve never seen another since. What’s more likely? That improper use by new owners was causing them to break, but that everyone learned to avoid that and that’s what ended the problem, or that a few of the parts were defective and that the problem was corrected in the manufacturing process?

That’s only one of several examples I could cite from my observations over the years, but that’s one of the most memorable.
And I still have those extra slide catch levers that I bought when I thought that maybe they were being broken by people who didn’t know how to operate them correctly.

I’m an Aimpoint fan and have long been leery of cheap optics, especially sights, but if we can’t trust a mounting screw to not fail as it’s being removed, that wouldn’t give me any warm and fuzzies about the rest of the unit if I were relying upon it for serious purposes.

Possible?
If we go down that road ... sure anything & everything is Possible.

But there's Possible and then there's Probable.
I don't believe much in coincidence myself.

I’ve never understood the “I don’t believe in coincidences” statement. To me it’s like saying, “I don’t believe people die from disease.” I have personally witnessed countless coincidences—unless we have totally different concepts of what the word means. The dictionary definition of the word is “the occurrence of events that happen at the same time by accident but seem to have some connection,” and that’s what it means to me.

In any event, I wouldn’t call the breakage of two parts in succession because they were either both defective or both had been over-tightened to be a coincidence. Although they both happened under similar circumstances, the “coincidence” element of happening at the same time by accident is missing because both were due to a discernable cause.

Or a person can look at what is the common denominator in a given situation.
The user is at least one.
But since neither of us witnessed the event , you go with your opinion of what's possible & I'll go with what in my opinion is just as probable.

Looks overtorqued to me. Torque isn't about tightness; it's about bolt stretch (or screw stretch). Max torque on a small screw like this is very minimal; a few inch pounds at best. If it's going to fail, it will be at a stress riser where the threads are, and as it can't fracture among the threads in use, it will fail where the greatest stress has occurred, just outside the part into which it threads, which it did. Two screws, same application, same user, points to the user, or a series of screws with identical flaws in the same place.

yep. I'm guessing it was my fault too, although I don't really remember the installation or how hard I torqued the screw or anything...

I haven't had the time to call sig. it's fallen below a few other things at work and home - maybe tomorrow. I'm interested in what they say.

I will also look into other mounts. I hadn't thought of that!

Cast ChiCom quality.

Any chance the rail slot or the mount locking insert the screw threads into is distorted? If the rail to mount interface is uneven that would also stress the end of the mounting screw. In your pictures there appears to be some damage to the underside of the mount near the mount locking insert.

ETA: Is there any chance the locking insert is installed upside down? Its edges don't look even with the rails on the underside of the mount.

This message has been edited. Last edited by: TooTech,