Tuning Extended reservoir Benjamin bulldog

That's spot on

But you loose your lower picatinny rail and ypu have to cut a portion of the plastic frame to allow the extended reservoir to fit.

Without the pitbull moderator the reservoir extends about 4.5" past te barrel.

With that said I like mine.

In factory form with extended reservoir you can probly get 10 more shots

Drilled transfer port and a tighter hammer spring you can expect 5 more shots.