The 4000+ fps with 50s was unattainable with even reasonable accuracy in any Swift I've owned.
The 40XBKSS came with a 27.25" bbl. We got well over 4k, closer to 4100 fps using IMR-4064 and H-380 behind 50 gr Rem PLHPs. Those bullets were the only things we tried that about never exited chucks. Pulped them, really. Nothing was as good out to 350 yds or so. Eventually we gave up on speed for the sake of less drift with 63 gr Sierra SMPs and IMR-4350 for the 350 to 450 yd shots. IIRC, we got about 3700 fps from that gun.
