A couple of weeks ago I found a Sig Rimfire Conversion for the P220 for $180 at a local gunshop. Since I love caliber conversions it was a done deal. I already have rimfire conversions for the 1911, Glock 30, and Glock 17/22, sadly none are threaded though. It fit great on the P220, but the magazine had issues of not wanting to stay seated. It worked perfectly if I hold the magazine in place with my hand, but something is wrong and I'll see about finding another mag soon. It is an older "Made In W.Germany" P220 so it may not work correctly for the older model. After checking examining the rimfire slide, it looked like it might fit on one or more other P series Sig pistols. I tried the 225, 226, 228, and 229. The P226 fit perfectly, so I ordered the rimfire magazine for it. It came in yesterday and I test fired it today with zero issues.
just lookin at the picture... the magazine latch cutouts looks different? the upper mag cutout looks to be lower then the lower mag cutout?