I have a sigp239 40cal. bought in 2002 that has 3 times blown off the front end of the slide where the rod and spring sit. First time was in 2005 and the 2nd time 7 months later. Sig said the front part was to thin so they were going to make adjustments in the manufacturing of the slides, but they replaced the slide at no charge to me. This last time was 4 years after but Sig says it blew because of excessive and constant shooting[?] so it's no longer under warrenty and want me to pay for a new slide. The gun has always been shot using proper factory ammo appox. 200-300 rounds per month and cleaned and maintain to their spefications using a Sig certified armorer. Has anyone else had this problem or heard of front ends blowing off? Is this just normal wear and tear or a malfunction on the guns part? Are they taking me for a ride? Any helpful info will be greatly appreciated, Thanks.