DD MK18 begining to keyhole

[Iraqgunz]

This isn't an ammo thread or a 9mm thread. Let's stay focused on the particular issue.

[eternal24k]

out of curiosity, any signs of baffle strikes?

[brodband]

This information came straight from DD as a buddy had the same issue with rounds starting to keyhole.

DD said that the older style 10.3" barrels with the larger (.080+) gas ports would erode quicker and bullets would not stabilize fully hence the tumbling.

I've got around 10k rounds through my DD 10.3" .070 gas port barrel and have not had an issue yet.

I've also been told that all the new 10.3" barrels coming from DD are correct .070 gas ports fwiw.

[markm]

Wow. I never heard of retarded ports messing up stability. Whomever spec'd their old ports should not be allowed near guns or live rounds. Just give him a styrofoam helmet and a squirt gun. (No water)

[tom12.7]

Yes, that has been shown to actually occur. That is one of many reasons to not port oversized, even with a possible restriction over that reduces some volume of gas. There's a couple of other interesting things that we could look into deeper if there is any interest.