For anyone who is interested, here is a picture of the barrel porting I had done on the 375JDJ barrel for my Contender G2. You can probably see that the ports are not straight drilled, but are cone or venturi shaped with the actually opening much smaller the the outer diameter. The man who did the work, Ray White at Warner guns in Warner, OK, told me he found that the cone shaped ports cushioned the felt recoil a scosh more then straight drilled ones. The ports are 10 degrees angled back. They did a nice clean job of it and the total cost including shipping both ways was $90.00. I will shoot it sometime this week and report back.