Got the chamber reamer, reamed the chamber, added a chamber peep hole, polished all rough spots. Put it together and fired 200 rounds through the barrel. Both the .40 SW and the re-chambered 9mm (now 357 sig) show identical wear marks. The firing characteristics are very close to each other. The 40 has slightly more kick and the 357 sig gets the most bang points. I can't understand why it is taking so long for the 357 sig to gain a decent following.

Just for the record, when I got close to the proper depth I cut and measured very frequently. I also reassembled the slide with a dummy round and measured the clearance until it matched the 40 barrel. The modification took around 6 hours total. The results were worth it. My SW40VE is now a dual caliber weapon. As for Smith & Wesson, I have heard that they did not like paying royalties to Sig Sauer. 357 sig is a registered trademark. I just think they couldn't sell enough to continue.