Gas Block Install Help

[ktwo]

Seems straight forward, right? Slide the gas block on the barrel, line up the hole in the barrel with the hole in the gas block, screw it down, and 'voila' your gas block is installed.



Eh, not quite so fast there, Baba Looey...



I'm installing a Geissele Super Gas Block on a BHW 18" barrel. The barrel has one dimple on the underside for a set screw type gas block. But I have some questions I can't figure out...



1. Is the distance from the dimple to the back edge of the mounting surface standard? Mine appears to be about 0.25". I can't get a steel rule inside the gas block but the distance from the back edge of the gas block to the set screw appears to be about the same. True? Or does it vary from manufacturer to manufacturer?

2. Is the relationship between the placement of the dimple on the underside of the barrel to the port on the top of the barrel standardized? How do I know if I utilize the existing dimple that the gas port will accurately line up the port on the barrel?



and finally...



3. How in the hell am I supposed to make sure that the hole in barrel lines up correctly with the hole in the gas block when I can't see or reach either one?



Thanks in advance



-K2

[GLSHOOTER]

The rear set screw on the bottom of the GB is directly below the gss port. Line that up with the dimple. Tighten it down. Go shoot.

On BHW barrels the dimple is standardized to be below the port just for this issue.

Greg

[lkrbuilder13]

Is that gas block a clamp on? I have noticed with the clamp ons that I have (bte) there is a slight radius in the slot where the hole was drilled for the hole probability before the slot was made so it would clamp. Worst case, shoot it and if it doesn't cycle, look there first.