http://suparms.com/products/750-adjustable-low-pro-solid-gas-block-melonite-finish

I installed one of these last month on a 6.8 build.
Instructions said to not jam it up against the shoulder but to back it off a certain amount of 1/000 and I cannot remember; but I had to go buy some feeler guages.

I suppose it is because it will heat up and expand.

I bought the clamp on type because I did not want to wrestle with slamming and bamming a tight fit into place.

I think I paid $87 from Brownells.

Do you have a vice jig-block for upper install work?:

http://www.brownells.com/gunsmith-t...r-15-upper-receiver-block-prod17094.aspx

They say the rule of thumb on gas blocks is that the gas block hole is oversized so it will have some grace fitting it over the drilled hole in the barrel.

Brownells has video instructions for free on you tube and you can purchase the entire video too.

Last edited by Robert_White; 09/24/16.
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