I know it would have to have the Sidewinder prefix at the very least, but I wanna know exactly which parts it would need to give it 9 shots (technically 3), and I know characters like Krieg have skills that negate the small clip size, but dammit I’m a stickler when it comes to my guns having a decent fricken’ clipsize right off the bat!
Not a specialist but the only part that can increase magazine size is if you have a matching grip. Jakob in that instance.
Fairly certain you just want a rustlers twister. Also kinda certain the best your gonna get is a 6 mag.
In my experience the Sidewinder has never been an optimal accessory.
This doesn’t specifically address your question, but this is actually worth watching :
The max is 7 without outside sources.