What is the name of this part of the Sig Sauer p229 airsoft pistol? ( point is in caps )?

After a few rounds of using my pistol in airsoft games, i notice that after one or two shots, bbs would stop feeding. after trying to unjam it and fire again, my gas leaks right out of the gun. I informed one of the technicians at the place of this problem and he told me that my magazine lip looked bent. upon further inspection, i noticed that it wasn't the magazine that cuased the misfeed, but the internals of the gun. after inserting the magazine and ing the gun back, i noticed that the slide would stop where the bb was supposed to be picked up. THE PART OF THE GUN THAT ACTUALLY PICKS UP THE BB AND PLACES IT IN THE BARREL TO BE FIRED. I tried looking at exploded diagrams but ended up frustrating me because i couldnt find the piece! Please help. Also, this is full metal and Gas Blow Back. ( if that information was at all important)