I am new to 1911s and have just recently purchased a wilson combat KZ-45 used at a gun show. Today was the second time I have fired it and have put about 200 rounds through it. I noticed that the trigger pull started becoming erratic going from very heavy to normal at about 3 lbs. I adjusted my grip and checked to see if I was doing something to bind the trigger. I chalked it up to being dirty then at about the third round it did a 2 round burst. I finished the magazine and put about 40 more rounds through it and did not have that happen again but the trigger still felt like it was going from about 12lbs to 3 lbs. I have done a fair amount of shooting with various hand guns and I know when I touch one round off to soon but this was a two round burst. Can anybody give me any suggestions?