M1 is mobil isnt it? We patterned boss extensively trying to get a good duck pattern with a mobil choke Beretta. We tried boss 1 1/8 4, and 3/5.
These are what I have from notes.
40yd patterns. factory chokes
Modified- #4 66% extremely blotchy with big holes. #3/5 69% tight core and extremely blotchy in mid and fringe
Full- #4 82% tight core, extremely blotchy. #3/5 80% tight core, extremely blotchy. (Lots of small holes- possibly fracturing)
40yd hevishot extreme range choke
#4- 91% bingo
#3/5 80% thin on fringe- blotchy
Just going off of memory, i dont think any of them were a good pattern for phesant going away shots. Tons of holes and very uneven patterns. Maybe "bingo" was good, i dont remember it off the top of my head.. must be a reason I wrote that. I actually probably saved "bingo" pattern paper somewhere, I usually do when I finally settle on a combo. I will look tomorrow if i remember.
I can count out 1 1/8 of boss #4 shot if you need me to, to figure out the percentages. Should be about 180 pellets though.