Lots of Questions

[Krink545]

Ok I’m waiting on my new Savage barrel that I’m getting from a member here.
It will be 17" and Ill thread it for my AAC762SD. I’m also looking to build and upper in the 10.5" range that will be used on my SBRed lower or my M16A1.

1-Will these 2 lengths require 2 different loads to keep them subsonic?

2-Im thinking of getting a barrel from M1S. I read here that their trim length is 1.4 while all others are 1.355 will the 2 different guns require different trim lengths?

3-Anyone here try a Adams Arms gas block conversion on their Whisper? I have one on a 223 upper and it looks like a prefect block for a Whisper. It has 3 different gas settings full, half and off.

Thanks for the help.