You can shoot any of the FX Hybrid slugs with no problem and other brand mid weights too. You do need to rotate your barrel 180 degrees to align the larger transfer port in position. Then its all about tuning .
The M3 has a Superior liner and most like to go to the Superior Heavy liner if only heavy slugs are to be used. Lots of YouTube videos available to help.
Dang it, you guys are going to talk me into slugs and I just got 10 tins of pellets and have another 10 on the way… I guess the new barrels on the M3’s are designed to shoot both with the dual ports on the barrel. I’m just thrilled with pellets right now so it will be harder to impress me. And I kind of think I need a 22 barrel and set that up for slugs.
