Its a good number.
Back when I could do 495x15 at 235, I was very sloppy in my descent and gathering power was pretty much non-existant.
My lowback strength and tightness was also LESS than it is today and I’m 10 years older.
I’ve seen utubes of guys benching 500 and it was “loose” and “sloppy” on the way down, lots of power “bled” out.
I didn’t realize how much tightness was when I was younger.
I guess I was saying, I was that guy too and could’ve been alot stronger at a younger age if I realized it.
I guess what I’m trying to say in short, is your doing good.
But I know you can do alot better, just like most can by gathering as much power on the way down.
If you are concerned about weight, footplacement is important. Widestance squats will give bigger numbers over narrow. Feet have to be pointed out some.
See I did my number with exact to shoulder width and feet pointed directly forward.
Another thing that is not going to hurt is doing front squats, or substiting out half of your back squat days for front squats. Saves the lower back over time.
Lowerback strenght, thru some non high school type lifts, such as good mornings, stiff leg deads, hyperextensions with weight, low back extension machine, etc.
Bar placement too, should be as low on the traps as possible. Many place it higher up a couple of inches even, and first it hurts more, second you have to work harder to stabilize the bar.