Ever since I did the conversion on my 12, I had some issues with some of the cheaper low brass field loads. Well, I ordered the reliability kit from Greg, also a Gas Port cleaning kit. I installed the new spring today, cleaned the gas port, and reamed it out with the brush. The pick is just right for cleaning the holes out. I thought I just had three open gas holes until I got the pick...turns out that all four are open and no obstructions. Put it all back together and after a few rounds ended up setting the knob on the number three setting. It flew through the box of cheap a*& Winchesters