Hmm...a Master score is, what, 95%? So he'd need to pick up just 5 more points (855) to make the cut.
You can do it!
So anyways, OP--I'm certain that any hardware you choose with decent length (longer sighting radius == good) and with adjustable sights (not having to apply any Kentucky Windage == good) will be good enough to get started, and even get you to shooting Master scores. A semi-auto makes things easier (faster reloads, more time to aim between shots) and is inherently more accurate (no barrel/cylinder gap for the bullet to jump before it hits the rifling).
I prefer revolvers for their reliability and their balance/feel. If a round doesn't light I can hold the trigger down and cock the hammer for a second try or I can just move onto the next round and take an alibi. I usually get a couple dud rounds in each 550-round brick of Federal #750 wally-world bulk ammo I use in my 617-4. I haven't taken an alibi since I started shooting Bullseye last year. Plus, I need something to do (cocking the hammer) between shots on timed and rapid =)
I'll echo melchloboo's statement that if you're going to do Bullseye competitively, you're going to need a lot of trigger time (thousands of rounds of live-fire + thousands more dry-firing), whatever platform you choose.
Though now I kinda wanna get a 22A or a Neos or a Buckmark and see how good I can get with one; maybe next season, or maybe I can shoot my revolvers for record and shoot other stuff for practice at the weekly matches--my league allows shooters to do that, if there are open slots on following relays.