I just tried to fit a 'semi drop-in' barrel to my personal XD Service (40) and am very disappointed with the results. i am an experienced gunsmith (6 years) and was looking for a somewhat quicker solution than doing a custom fitting job which can take me as long as 8-10 hours to do correctly. 1. the barrel would not permit the slide to go into battery a shipped. 2. The chamber was so tight that hand loads that easily fit into a Dillon chamber gauge had to be forced into the barrel. 3. Once i managed to get the slide into battery, the barrel jammed against the frame. After 4 careful hours of fitting, i had a barrel that would cycle, but not feed at all. Barsto makes an excellent product for 1911s. Had they called this barrel a gunsmith fit, i would not have quibbled with the work required at all. but 'semi' drop-in is a real stretch here. i realize that not everyone experiences problems like this -- but the chamber was not even chamfered -- which is what you would expect for a barrel of this quality.