Trying to figure out where to get recoil springs, Wolff springs doesn't make em. I tried the gun out earlier tonight with the handloads I've developed for my S&W. This is a 180 grain hollowpoint, as you can see in my scan, and 24.5 grainds of H110 powder. The gun definitely needs more recoil impulse, it shot like a 9mm and didn't always shoot to slide lock on the last round, I think it was short cycling to a certain extent. I think the recoil springs might be a bit weak because the gun didn't want to go into battery a couple of times. A firm shove on the back of the slide put it into battery and away we go. Ammo might have had ALOT to do with this, the bullet profile is NOT designed for a semi auto (check the pic!) and my casings have already been fired a few times and need to be thrown away, they were rough and discolored.
With the H110 powder, firing at about 8:45pm just after the sun dipped below the horizon, the gun produced an authoritative BOOOM and muzzle flash erupted from it. Most impressive muzzle flash I've ever seen, it blinded me with every shot, not only did I lose a sight picture, I was literally seeing spots and couldn't even see my arms in front of me for a couple of seconds! I had another fellow who happened to be at the range touch off a round and saw that the flash extends about 3 FEET past the barrel in a huge cone of fire. This gun is SO Hollywood.
All the mags fed and functioned fine except one, the only mag with the metal floorplate (again see pics). The other 3 I have, with the plastic floorplates, ran just fine. Extraction and ejection were fine, although I had to have help recovering casings, the muzzleflash was so great that I couldn't actually see the gun cycle or see the spent casing come out. Un-friggin-believeable, I really need to figure out how to capture that muzzle flash on film.
I think I'll call Magnum Research on Monday and ask about the recoil springs. Oh yeah, the MkI/MkVII series do not allow the caliber changes, but I've shot the .50ae with factory loads and it wasn't a pleasure to shoot. This setup is actually fun to shoot and very tame, while being potentially the most accurate of the calibers offered. Optimal for my taste.