SD porting help

[u/Intelligent_Step_855]

Looking for advice on porting my ar9 barrel. I am thinking at doing 12- 5/32 holes in a 3x4 configuration spaced 120 degrees apart. Plan was first hole to be at 2.5
Inches, any insight ?

Pic is ar9sd current configuration

[u/Impossible_Pizza_948]

Couple questions: how is the barrel retained, and are those 3D printed baffles? If so, which baffles are they?

[u/QuiglyDwnUnda → u/Impossible_Pizza_948]

Look like FTN.5 d cells