M1S Barrel - MK 220 Cartridge Length

[Scouter]

I just got a new M1S upper and started developing a subsonic load.
The first item I check is proper COL using a dummy round with a MK 220 bullet. I'm getting land interference at 2.273". So, 2.260" COL should be OK. Anyone have a recommended COL for the MK 220 in a M1S barrel?
Thanks.

[N310toN170]

Try to stay between 2.250-2.260, the primary concern here isn't land engagement but reliable magazine feed.

[pomofo]

Check with 2.260 just to make sure. My M1S throat is so tight that I had to load down to around 2.160.

[Colohunter]

I don't have my info to check my load length right now, but I had to load short for my M1S uppers as well.