AR 15 Gas Block Question

[dfletcher]

I want to switch out my existing plain old front sight for a single railed "no sight" gas block. Pretty sure I understand the removal part - drift out the two barrel pins & gas tube cold rolled pin. I've looked around at a few gas blocks. Do the two set screw types stay put? And - how can I be sure the gas ports line up? Any fitting required?

I'm pretty comfortable with my own mechanical abilities - can do a basic build (have done 3 so far) and work on Smiths & Colts, 1911s and Garands, but my gas block experience is zero.

I do want to keep it simple and sturdy and would use this type: http://www.model1sales.com/item-deta...TOKEN=26992511

I see alot of blocks secured by two set screws against the barrel - are they sturdy?

[mltrading]

The set screw type gas blocks are OK. Just need to tighten the set screws.

As for the alignment, here are some suggestions.

1) Check the bottom side of your GB, there should be a hole that aligns to the gas port hole (of your GB's gas port hole).

2) Install your new GB up side down and align the hole mentioned in (1). You can visually align the gas port of your barrel and the hole of your GB.
Then do some marks related to the GB on your barrel.

3) Flip your GB to normal position. Then tighten the set screws with the marks/GB aligned.

4) If you are not satisified with the set screws, you may drill the GB and pin it.

*** If there's no such hole at the bottom side of GB, you need use a caliper to measure. No other easy way.

[ar15barrels]

Drill a detent in the barrel.
Put the setscrew into the detent with rocksett or red loctite.

[dfletcher]

Thanks for the assistance, I think I can handle the work. Had forgotten about drilling the dimple when using the set screws.