In summary, the man is asking for advice on using bolts for a squat rack. The man attached a picture of the bolt setup he is using and explained the lines he used. The white circles are M16 bolts, the red arrow is a pivot point, the yellow line is 880mm long, the pivot point to load, and the blue line is 1000mm long. A barbell sits inside the green slings. The man squats up to 500kg, and the bar could fall a maximum of 1000mm. The man asks if 2x M16 bolts are big enough.
Stickyman: For one thing, if you could measure the static deflections described in post 18 (paragraphs 2 and 3) and post 30, for your current setup, that would be helpful.
Regarding the post 36 sling, my first impression was, it could be expensive, because it is not reusable. And, it seems it might be too short when contracted, and too long when extended, to be usable for the barbell sling (?). And the post 35 sling might be too elastic (?), but I am not sure.