Provided you hit parallel, I’d say 300 is pretty good, especially if you haven’t really trained legs much. Regardless of the weight you use, you should focus on a quick transition from eccentric to concentric and drive the weight up with as much speed as possible. Here’s something that has worked pretty well for me in the past for increasing strength.
Weeks 1 & 2
T - Back squat 10 sets of 5 at 70% 1RM (add 10 lbs 2nd week)
Straight leg deadlift 5x5
F - Front squat 10 x 5 at 70% 1RM (add 10 lbs 2nd week)
Deadlift 5x5
During squats, when I was doing the work sets, I would start a new set every minute. I was done with all the work sets in less than 10 minutes, but it was pretty brutal. I would then take up to a 15 minute break before doing deadlifts. For deads I started a new set every 2 minutes. The percentages are estimates, probably a little lighter than a 10RM for the squats. It's a hard workout, but only takes around 30 minutes.
Week 3
T - Squat 8x3
SL dead 5x3
F - Front squat 8x3
Deadlift 5x3
During week 3 I used the same weights that were used in week 2
Weeks 4 - 6
T - Hang Clean 3x5
Squat 3x5
F - Hang snatch 3x5
Front squat 3x5
Deadlift 3x5
I started these workouts with several low rep sets of plyometrics and sprints, usually 2 - 3 sets of 2 exercises. I used the same working weight for all sets of squats. You should be able to start off week 4 with about 20 - 25% more weight than you used in week 2. Add 10 lbs in week 5 and another 5 - 10 in week 6. Oh, and rest periods between sets are 2 - 4 minutes. For cleans, snatches, and deadlifts I added weight each set if possible.
Week 7 (recovery week before moving on to something else)
T - Hang clean 2x4 @ 80% of heaviest 5 rep set
Squat 2x4 @ 65% of heaviest 5 rep set
F - Hang snatch 2x4 @ 80% of heaviest 5 rep set
Deadlift 2x4 @ 65% of heaviest 5 rep set
Or you could try the 4 week base Smolov squat cycle (404 | Dragon Door) but then you’d need to squat 4x/week.