Picked up my Hexium 762 today and noted some things that may limit the choices of HUB adapters that work with the can. First is the short blast baffle distance from the end of the can. It’s 1.45” on the 556 and 762 cans, and only 1.25” on the 300 can. Also, the inside of the can has an internal taper about 1/2” deep where the internal threading ends. This mates with a matching taper on the Sig adapter, presumably to keep the adapter from unthreading from the can. What this means is that if you have an adapter with a threaded section longer or deeper than 1/2”, it won’t go all the way into the back of the Hexium. I’m using GA Plan A adapters, and the Long version fits fine (it goes in about 3/8”), but neither the original short Plan A, nor the XL will fit because their threaded section is too long. The ECCO machine Griffin Long and short also fit as they are slightly shorter than 1/2”.

The attached photo of the included Sig DT adapter shows the taper starting at 1/2” from the flange that mates with rear of the Hexium.

Check your adapters, folks. Not all will work.

I had this problem with my B&T surefire hub adabpers. I really wish that HUB was a bit more specific about the dimensions or a minimum on the clearance to the blast baffel, or at least the mfg. would publish the allowable clearances so that you can figure out if the HUB adapter you want to use will fit on the can you want to buy before you buy it!

That's kind of a bummer that can makers are taking the "U" out of HUB and they aren't Universal anymore. We had been making some progress where we could interchange mounts. I think movement towards proprietary systems is unfortunate, as I hear good things about this generation of SIG silencers, but limiting mounts is a turnoff for me. Do they really need to shorten things up that much on a 6.2" can?

In the 5.56 world for a long time it seems like manufacturers were fairly standard on 1.7" blast chamber length, to fit the muzzle devices from 14.5" Pin & Weld barrels. Starting a year or so ago, manufacturers started going shorter and it seems to be a growing trend. I understand going proprietary on something like a CAT KK micro can at 4.5" long. They are fighting to use every 1/16" of an inch so they are using the Nano mount that only extends .84" past the muzzle.

I'm a little surprised to see this trend continue into the 6" full size cans. We always want quieter cans, and it looks like maybe they are figuring out they can trade a shorter blast chamber and fit in one extra baffle and squeeze a bit of performance.