Hi, I purchased a glock 357 magazine for my glock 23, the .40 cal. I was told they are the same and if i recall correctly they are. But loading the 357 mag i cannot seem to get that 10th .40 round in the mag! Only 9. I tried with the glock speed loader and it cracked the plastic speed loader! is there a problem with this mag or am i just retarded? thanks in advance.