I have a custom built Fusion Firearms Long Slide hunter with a 6" barrel. It was built to fir 10mm cartridges. Now I found out that Fusion will fit in a new slide, barrel, and recoil spring, and I camn also fire .40 cal S&W from the same gun. Kit would come with said slide, spring, barrel, and 1 magazine. It would cost me $355. But that is cheaper than most new .40 cal pistols out there. Now the thing is I already do own a SIG P229 with both a .40 cal and 357 SIG barrel. Hmm, I wonder if Fusion could also fit in a 357 SIG barrel? That way I might be able to have one pistol that fires all three cartridges. I could sell the SIG. Should I, or shouldn't I.