Gas block buis height

[blue109]

Planning out this matrix build. Any issue using a standard ar15 gas block front sight on a rifle length setup ? Do I need a 308 specific height? If I'm not mistaken there's about 1/16" difference. Can you compensate for that? Pri selLS ar15, DPMS, and AR10 specific front sights.

[Robocop1051]

There are different height FSGB's, like the F marked vs non-F marked. Definitely check out PRI or Vltor, as they're probably the pinnacle of FSGB's. I think ARMS makes one too.

[blue109]

I'm planning on the PRI. I already have one on a different gun. I'm just wondering if any of the AR10 guys know if a standard AR height sight will work. I wanted to swap parts around and use my DPMS receiver for this configuration so I wouldn't have to worry about the height, but that's not going to work now.

My issue here...is I tend to move parts around and reconfigure. I'd prefer to buy parts that will work on more than one of my rifles.

Edited July 2, 2015 by blue109

[98Z5V]

If you're just talking about the PRI pic-mount flip up (for a rail, for example), then you can use any one (not the crazy-height picatinny gas block sights, though).  There's more than enough adjustability in the front sight post to account for a minor height difference.  If you should fall short, a few companies make front sight posts that are 0.100" taller than standard.  Don't think you'll have an issue, brother.

[Robocop1051]

I think KNS makes that post. They are like $8 at most major websites, like Brownells.

[98Z5V]

Yep.  They make a bitchin' GoPro mount for a pic-rail, too, and I need to pick that bastard up.

Edited July 2, 2015 by 98Z5V

[blue109]

I'm talking about the mod0 front sight like the ones we use on the SPRs.

The plan was to do a mk12mod0 looking 308 build on my current gun, and swap my current guns parts onto the new matrix receiver. After talking to Tony at PRI today it's not going to work out, so I have to use the matrix as the mod0 ish build. They make an AR10 specific front sight, but I'd rather buy the standard one.

[98Z5V]

Now we're talking.  You're effed, on the "any sight" thing.  You need to use the AR10-height one, brother.  Different receiver top heights compared to the height-over-bore between AR15s and 308ARs, and those sights are different.  The Matrix set is basically AR10 based, so you won't run into problems running the PRI AR10 flip-up gas block assembly. 

 

That's gonna be a badass rifle, man.  <thumbsup>

[blue109]

Update...I love PRI.

Tony emailed me back last night. My issue was I have a 14" pri tube on the Fulton armory gun. That tube won't fit an AR10 based gun. The tubes are the same, but the alignment pins are slightly different where they hook into the barrel nut, so I was stuck with the long tube on that gun and the 12" mod0 tube for the matrix. Tony said he was thinking about it, and said I could swap the pins and shims to make the tube fit. He offered to sell me a DPMS 12" tube with the AR10 barrel nut and a spare set of pins and shims for the 14" tube to fit it to the AR10 nut. I can use the AR15 height sight on my Fulton.

Back on track.