Adrian said "Yeah. I wish it was as easy as a vial but the serums have to be calibrated and balanced out against each other each time. Only reason Jarvis does it is because my hands get shaky and I can't afford to lose a dose. I was working on a pneumatic gun, but as you can see I didn't finish it. The closest thing I've seen to what I need is used by HYDRA medical staff and I'm not looking forward to running into HYDRA anytime soon."
Adrian machined the components and the housing for the compressed gas that would trigger the actually injection but the hardest part was milling a nozzle that could secure a sterile needle without warping or bending the needle. He'd put a safety on it like any other gun he'd ever had and he'd been trying to figure out if he could make a backup system just in case.
"I've gone through a dozen different alternatives including putting a port into my chest like Stark but I don't like the thought of having holes aside from the one I shovel food into."
He pointed to his notes so Doctor Banner could see for himself. For being a solder type Adrian was a genius at engineering. He made his own armor and weapons from scratch with precision components he fabricated himself.