yesterday I installed a trigger shield in my new Mark II, went out and shot 250 rounds threw it, I didnt count, but I bet I had a stove pipe about every 25-35 rounds shooting CCI Mini-Mags, after 200 rounds, switched to Federal Lightnings were I had at least 1 if not 2 in every 10 round mag, all resulting in damage to the next round being chambered, had 1 that was dented bad enough that I couldn't chamber it at all...Is there something I'm doing wrong, or a possible problem I should be looking for? Keep in mind that it is a brand new Mark II and have only put 450 rounds threw it total since I bought it 1½ weeks ago...I did clean it while I had it apart installing the trigger shield, Mostly with a blow can then oiled any part that looked like it should have some oil, being carfull not to oil the bolt face...wondering if maybe I over oiled it, dont see how this is possible, but am fairly new to semi-auto's, I've always been partial to High-powered rifles, my current passion is a 7MM Mag...something about taking out a water bottle at several hundred yards gives me a thrill....anyways I'm jabbering....any suggestions on the stovepipe issues would be greatly appriated