Home / Equipment / Ball Specs / Crown 78U
Brunswick · ball specs
Brunswick Crown 78U specs
The Brunswick Crown 78U is a urethane ball with the Tiered Hexagon core. Here are its published specs, how they compare with the other current balls in our table, and what the numbers mean on the lane.
Disclosure: this page has affiliate links. If you buy through them, we may earn a commission at no extra cost to you. As an Amazon Associate we earn from qualifying purchases. How this works.
| Coverstock | Urethane Solid 78D |
|---|---|
| Cover type | Urethane |
| Core (weight block) | Tiered Hexagon |
| Core type | Not stated |
| RG | 2.549 |
| Differential | 0.046 |
| Factory finish | 500, 1000 Siaair Micro Pad |
| Maker's category | Advanced |
| Color | Purple / Grey |
| Weights | 16-12 lbs. |
| Release date (maker) | December 11, 2025 |
| USBC approved | 2 December 2025 |
Numbers as Brunswick publishes them, checked 21 October 2026. Published for a 15-pound ball. Drilling changes how a ball behaves, so a pro shop's layout matters as much as these numbers.
Find the Crown 78U on Amazon → Compare with another ball Add to my arsenal
What the numbers mean
RG 2.549. That is lower than 13% of the 134 current reactive and urethane balls in our table, so it sits on the high side. Storm says "a high RG ball delays its revving, offering more length and angular motion down the lane."
Differential 0.046. Higher than 46% of the balls in our table. Storm says "a low differential ball tends to have a more predictable, controlled motion."
Urethane cover. Storm says urethane covers "displace oil rather than absorbing it" and are a popular choice for spares and shorter oil patterns.
USBC allows an RG from 2.447 to 2.813 inches and a differential of at most 0.060 inches (Equipment Specifications Manual, March 2026). Our ball spec table lists every current ball we track, and who makes bowling balls covers which company owns Brunswick.
Balls with similar numbers
Same cover type, closest RG and differential in our table:
- Storm Pitch Black: RG 2.560, differential 0.023
- Hammer Purple Pearl Urethane 78D: RG 2.632, differential 0.034
- Storm !Q Tour 78/U: RG 2.650, differential 0.035
- Hammer Black Pearl Urethane: RG 2.650, differential 0.015
Sources: Brunswick product page; Storm, "Inside The Bowling Ball"; Storm, "The Coverstock"; USBC Approved Ball List (20 October 2026); USBC Equipment Specifications Manual.