+1 on the magazines, add MecGar to the list of good mags. KimPro magazines are very good, but the standard Kimber magazines are a crap shoot. I always swap out all the springs with a Wolff spring pack whenever I pick up a used 1911. Also, this is extremely rare, but there can be a burr on the barrel bushing, which can drag on the barrel. Look for a lengthwise scratch on the outside of your barrel if you suspect this, but it is one of the very last things to suspect.