It has been a journey for me switching from low-bar squats to high-bar squats over the last 5 - 6 months. I was up to 365lbs for 4-5 reps with the low-bar, but felt as if I was not engaging my legs as much as I should be. In fact, I was beginning to feel the exercise a lot more in my lower back and I seemed to be "bouncing" at the bottom of the movement.
When I made the switch to high-bar, I had to significantly drop the weight. It took me a few weeks to even get used to 225lbs. This is because with a high-bar squat you need to keep your chest up and really "sit" at the bottom of the movement. My flexibility was making it very hard for me to maintain an upright position with my chest at the bottom of the movement. But with proper stretching and warming up, I was able to fix my form and make gains.
For today's leg workout I was able to work my way up to 305lbs for 5 reps on my last set of squats.
The progression was:
Set 1: 275lbs
Set 2: 285lbs
Set 3: 295lbs
Set 4: 300lbs
Set 5: 305lbs.
Check out the video below. I was getting pretty fatigued around my 4th and 5th reps, but I was able to adjust and get under the bar to complete them.
**A quick tip for when lifting heavy. Take in a breath before each rep. Make sure you have a nice strong "internal belt" going so your core is as strong as possible to prevent you from falling over. This will also help you to stay upright with heavier weight.