Track one actual traffic shot at a time from a ball card, or repeat the last one ×5 — a league game is roughly 15–20 shots on the pair. Reactive generally depletes more oil; slow-oil covers can leave more available to move downlane. Traffic and flare matter, so this is relative — not mL per shot. Brighter blue is carry; exposed wood is depletion. Display contrast is boosted.
No traffic tracked yet.
Shared links open fresh. Sources: USBC team simulation (reactive/urethane), USBC equipment manual (slow-oil spare balls), and Kegel traffic observations (low-flare spare carry). Relative, not universal.
How early the ball revs up. Lower RG = the engine spins up sooner, so the ball stops skidding and starts hooking earlier. Higher RG = longer skid, more length. The five strong balls here all sit low (2.488–2.515), so they rev early — the motion differences between them come mostly from cover and diff.
How much the ball "flares" — laying down a fresh, dry ring of cover on every rotation. Higher diff = more fresh cover gripping the lane = more total hook and stronger recovery. 0.058 (Black Widow) is big; 0.030 (Rhino) is tame.
How defined the breakpoint is. Higher asym makes the ball stand up and change direction more sharply instead of arcing smoothly. It shapes the move; it doesn't create raw hook by itself.
The shell does ~70% of the talking. Solid + sanded (500/2000) grabs oil early and arcs. Pearl + polished skids long and snaps late — the "hockey stick." Hybrid sits between. Urethane is a slow-oil cover: it absorbs far less readily than reactive resin, revs early, arcs, and hits flat — control, not power. Oil left on the surface can move downlane, but USBC testing shows carry ordering changes with traffic and flare; “urethane always carries most” is too simple. Plastic barely hooks at all — that's the spare ball. Cover usually beats RG/Diff for first impression.
Each ball card also rethrows your exact release with the target missed by 1 and 2 boards each way. Where those five shots finish is the ball's real miss room on this pattern — shown as a bracket at the pin deck. On a walled house shot misses converge (the dry outside saves a wide one, the mid-lane oil holds a tugged one). On a flat pattern the spread stays wide: a miss is just a miss. Small spread = forgiving look.
Oil = no friction = skid. The ball only hooks where it finds dry boards: past the end of the pattern (the "backend") and out by the gutter. More oil or a longer pattern pushes the hook later and weaker.
A house shot is a funnel — 8–10× more oil in the middle than outside, so a miss right hits dry boards and recovers, a miss left holds. Championship patterns are nearly flat (the 2025 Open Championships sheets ran ~2:1), so there's no free recovery: a miss is just a miss. It's not less oil — 2025 volumes (28–30 mL) beat most house shots — it's the missing wall. That's why accuracy and a controllable ball beat raw hook in Reno. USBC seals each year's patterns until the tournament ends, so the presets here are anchored to the last published sheets. Two more 2026 OC equipment rules worth knowing: entrants register a maximum of eight balls, and only 78-durometer urethanes are legal — the classic Purple Hammer is on the ineligible list.