Good points Reed.
You’ve just got some patellar tendonitis… I’ve had it to one degree or another for the last 8 months or so. It’s not exactly an injury, it’s just tight quads, and there are worse things than having tight quads.
What I do is wrap a tensor bandage around my patellars fairly snug and it relieves the majority of pain and I can keep squatting. You’ll have to play around with it a bit to get it right.
Don’t worry, as long as you’re squatting deep there’s no way you can blow out your patellars from squatting… it takes a lot more force than what anyone can put on their backs to do it.
Also, if you’re really sick of the pain, simply getting on your knees and sitting on your heels for a few minutes really loosens up the quads. I don’t personally do it as I love tight quads, you can get out of the hole with anything.
As reed suggested bring up your posterior chain, especially the glutes, as well as keep squatting deep the way you are, and you’ll have a monster squat in no time man.
I would suggest a different loading pattern than simply working up to 315 and doing as many reps as you can 3x a week. I admire your tenacity, but I feel there are better ways. Let me know if you’re interested in a kick ass 3 day a week squat program that’s a bit more structured.