Does the BCA work in ANY AR10 rifle, or have you only tried it in your Aero M5? BCA is at the very bottom of my list of AR parts suppliers. Garbage.
Are you sure it’s the BCG, and not an issue with your upper?
Right now is the worst time in history to buy AR’s and AR parts. Not only is supply low and prices high, but companies are shipping parts out as quick as they can and QC is slipping badly.
M5 BCGs go on sale a few times a week on Aero's website. You just have to be patient and sign up for notifications. I got a nitride a month ago for $229 shipped. If you sign up a new email you get 10% off.
BCA? That's literally the worst US maker for AR 15/10 parts. Plus the hire illegals so..