@dcashel
I have some data from Joe Marler with DD that I will post when I get home tonight. Basically supporting what you are saying....
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ETA, I hope Mr. Joe Marler does not mind me posting this, but his reply to me on the gas port question I asked him, when I was considering cutting down my barrel from 11.5 to 10.3, but as noted above, I am staying with the 11.5", changing the MLok to a DDM4 Lite, 10"
I had a M4 on order with Brownells, but called today and on back order until April, canceled the order and will call DD tomorrow and see if they have in stock
Hi, Richard. with regard to port size, that would really depend on whether or not you have a current production 11.5" barrel with the .069 gas port. If you look at the lot number on the barrel, there should be an "M" at the very end if it's the new port size. if you have the older barrel with the larger gas port, the M won't be present.
If you do in fact have the smaller gas port diameter, you shouldn't have to do anything to the gas port. If you have the larger gas port, it'll still work but could be a little overgassed.