I have experienced the same problem but it was much more embarrassing. I went through 2 and a half mags trying to take down 5 steel plates at an IPSC club night!!! They were maybe 10 yds away. One guy say's "Ive shot IDPA with this guy numerous times. He usually shoots pretty good,,something wrong with the gun?,,,sights out?" So we put 5 steel plates down and one of the other shooters took them out with 5 rds at the same distance. It was all me.
How often and how many rounds are you shooting? This sport needs consistency. Shoot the same damn gun as much as you can. 3-4 times a month i find is the bare minimum to stay sharp and somewhat competitive. I find switching back and forth with different guns hurts you as well. Don't get me wrong I love bringing 3 guns with me to the range and blasting them all off. But to stay at the top of your game you have to mainly shoot one platform consistently. That's just me anyways.