SIGforum
Are all Picatinny rails not created equal?

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January 23, 2019, 03:07 PM
Expert308
Are all Picatinny rails not created equal?
I have a Springfield XD-M that's been my nightstand gun for a while now. It wears an older Streamlight M6 light/laser unit, and it's always worked fine. The gun does double duty as a carry gun and the M6 comes off for that. On, off, on, off, continuously for years now, and it always snaps securely back and comes back to zero.

Now, I'm looking to add a light/laser to either my Beretta M9A1 or a Rock Island (Armscor) 1911. Whichever it turns out to be will replace the XD on the nightstand. So I started with the M6. Problem is, it doesn't fit right on either of those guns. It snaps onto the M9 fine, but is loose enough that it rattles around. Keeping the laser zeroed would be a real problem there, not to mention having the thing flopping around on there while I'm trying to shoot it. And the M6 won't even go on the RIA gun. The slots in the rail are deep enough that when I try to slide the M6 onto it, the body of the M6 impacts the front face of the rail rather than slipping under it. The M6 doesn't have any provision for adjusting the fit to a particular gun.

So my question is, is the MIL-STD-1913 rail not as "standard" as it should be? The XD seems to be the Goldilocks gun as far as fit goes, the other guns being either too loose or too tight. Is this a known problem that I just haven't run into until now? Is there a list someplace of what WMLs fit which guns? I'd like to get a newer, smaller WML to replace the M6, but short of buying multiples ones and hoping to get one that fits, I don't know which one to go with.
January 23, 2019, 03:36 PM
RogueJSK
Yes, there's a standard. But different companies adhere to it with varying degrees.

Unless it's specifically described as being a "1913 Picatinny rail", it probably isn't 100% faithful to the standard. For example, nearly all Sigs have a rail that's not exactly standard, yet work with nearly all Picatinny attachment accessories. But Sig's Combat models specifically have a 1913 Picatinny standard rail.

Many newer WMLs comes with a variety of interchangeable rail "keys", to allow for a customized fit to work with different handguns' rail dimensions.
January 23, 2019, 04:10 PM
CD228
Rogue is correct. In fact some of the old streamlight manuals they mentioned that the light could fall off certain pistols because the rails weren't size matched to the light. My m300 came with several different inserts just like Rogue said.
January 23, 2019, 04:46 PM
Pipe Smoker
Re: “It snaps onto the M9 fine, but is loose enough that it rattles around.”

My Beretta 87 Target has an integral Weaver rail – similar to the Picatinny, but not identical. So I’m wondering if your Beretta M9A1 might have a Weaver rail.



Serious about crackers
January 23, 2019, 05:59 PM
Expert308
quote:
Originally posted by Pipe Smoker:
Re: “It snaps onto the M9 fine, but is loose enough that it rattles around.”

My Beretta 87 Target has an integral Weaver rail – similar to the Picatinny, but not identical. So I’m wondering if your Beretta M9A1 might have a Weaver rail.

Beretta's site says "Firstly, there is an integral Picatinny MIL-STD-1913 rail situated under the barrel, for easy attachment of accessories such as tactical lights and laser aiming devices." Of course, I suppose it's possible that was written by someone who made a bad assumption, but given that the M9 is a military contract gun I'd be surprised if it isn't the standard Pic rail.
January 23, 2019, 06:39 PM
hrcjon
Its like dating. The light guys want it to work on a bunch of non std. rails (like sigs mostly etc.) and the mfg. really hate that 'real' 1913 rails are sized that many find them annoying. So some combo's work and get married, and some don't. An M6 is old enough and has perhaps been mounted enough that its just tired. Mostly the mfg. will tell you it fits a real rail. After that you need to research it. Generally the best light guys will tell you. For example I use the surefire x300 and it includes adapters for real rails and not so real rails (like glock).


“So in war, the way is to avoid what is strong, and strike at what is weak.”
January 23, 2019, 08:08 PM
Expert308
I went and looked at Streamlight's site and it pretty much says the same as Rogue did, at least for the newer units. I expect I'll see the same at Surefire. Thanks for the feedback, all.

This message has been edited. Last edited by: Expert308,