Barbell knurling is the crosshatch pattern on the shaft of Olympic Barbells that is intended to increase
friction between your hands and the bar and thus improving grip.
Grip level: moderate
Use for: Olympic Lifting and general gym use.
A Hill Knurl Pattern is often not initially designed to be a hill, but ends up happening from prolonged use and abuse on a barbell that uses mild (soft) steel. A Hill Knurl is one in which the individual “diamonds” have rounded tops instead of points. The rounded tops lead to a knurl feeling less aggressive and therefore more difficult to hold onto. When you’re going for a max clean and jerk, you want the bar to dig in. Even if you’re just doing warm-up reps for barbell rows, you don’t want your grip being the limiting factor.
Grip level: aggressive
Use for: everyday powerlifting training where optimal grip is required without tearing your skin apart.
A Volcano Knurl Pattern is the most optimal barbell knurling pattern that is currently available. Rather than just the sharp points on the Pointy Mountain Knurl providing the friction, Volcano Knurl has a “rim” of sorts that is the sharp point of contact with the hand that provides grip. Instead of just a sharp point, a Volcano Knurl has a rim/circle that is sharp which is more surface area providing grip to the hand.
Grip level: very aggressive
Use for: competitive deadlifting where ultimate grip is required.
A Pointy Mountain Knurl Pattern is essentially what you’d expect. It’s a diamond shape with a point that makes the most contact with the skin of the hand. This drives into the skin and allows the bar to stick better during movements like deadlifts. This type of knurling pattern is commonly found on very aggressive power bars designed for one rep maxes in powerlifting competitions. It’s also found on many different deadlift bars.