
Quote HistoryQuoted:
I have two barrels from 2013. Would be nice to get some of the gas to face cut down with properly sized gas ports.

What's the best way to measure the gas ports?
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others answered your question of how to measure. For me, calipers are not good for this, or it might be OE (operator error). I get within +/- 0.008, but with gas ports, you are measuring such a small opening, that is a wide margin. Pin guages get you to +/- 0.0005, or better than 10X the accuracy.
As to how to address the issue of an over-sized gas port, you need to first assess if it really matters. Are you having problems? If not, fogetaboutit. If you are, then you can buy new barrels for $250 to $290 each, or have the gas port plugged and re-drilled, probably at 90 degrees off center, give or take. This means that your barrel extension needs to be removed and a new one installed, headspaced and pinned. For only two barrels, that will likely cost you around $150 per barrel, give or take $40. I have a good source for that, if you want to go that route. If you go that route, really depends upon budget and how new the barrels are.
You can always call DD and ask them to replace. Not sure what they would say. I imagine if you can show issues, they would be more sympathetic.