Hello, mZugu:
I have a Francotte almost identical to the mentioned Boland, in 450 BPE (the third fastener is square, not the usual round Greener). The rifle shoots quite well (2" apart at 50 meters, sometimes better) with 71 grains of Tubal 5000, a 1" wad of green foam and 350 grains Hornady and Woodleigh bullets. With the same charge and wad, also shoots very well with Hornady 300 grains HP bullets. It makes a very good job in our driven hunts in Spain, very light and handy.