Bowling ball core · Roto Grip

Roto Grip RST Core

The core inside the Roto Grip RST line

An asymmetric core with later rev-up, more length and high flare, built for heavy oil. Balls with this core are no longer available at BowlersMart.

  • Asymmetric
  • RG 2.530
  • Diff 0.053
  • MB 0.016
Roto Grip RST symmetric core shape inside the ball

Specs

RG AT 15 LB

2.530

Later rev-up, more length

Revs soonerRevs later

71% of the reactive and urethane balls we stock have a lower RG.

DIFFERENTIAL AT 15 LB

0.053

High flare

Less flareMore flare

76% of the reactive and urethane balls we stock have a lower differential.

MASS BIAS AT 15 LB

0.016

Mild asymmetry

MilderStronger

33% of the asymmetric reactive and urethane balls we stock have a lower mass bias.

RG How soon the ball revs up.Differential How much the ball can flare.Mass bias How asymmetric the core is.
Roto Grip RST Core specs by ball weight
Weight RG DifferentialDiff Mass biasMB
16 lb 2.520 0.049 0.015
15 lbUsed on this page 2.530 0.053 0.016
14 lb 2.550 0.053 0.016
13 lb 2.570 0.032 0.010
12 lb 2.590 0.029 0.008

Source: Roto Grip published specs, as shown on BowlersMart’s original Roto Grip RST core page (2022). RG and differential change with ball weight; use the row for the weight you throw. The highlighted 15 lb row is the one used on this page.

Looking for a ball like your RST?

Balls with the Roto Grip RST Core are no longer available at BowlersMart. These in-stock balls have the closest RG and differential.

Hammer Zero Mercy Hybrid Bowling Ball

Hammer Zero Mercy Hybrid

Hammer HK22 C2 Hybrid Reactive

Medium to heavy oil

Sale price $194.95 Regular price $279.95In stock
Hammer Fallout Bowling Ball

Hammer Fallout

Hammer HK22 C2 Solid Reactive

Medium to heavy oil

Sale price $169.95 Regular price $269.95In stock
Brunswick Infinity Quest Pearl Bowling Ball

Brunswick Infinity Quest Pearl

Brunswick EVO Pearl HK22C Reactive

Medium to heavy oil

Sale price $169.95 Regular price $269.95In stock
Motiv Apex Jackal Bowling Ball

Motiv Apex Jackal

Motiv Propulsion MXV Pearl Reactive

Heavy oil

Sale price $219.95 Regular price $289.95In stock
Roto Grip RST Hyperdrive Pearl Bowling Ball

Roto Grip RST Hyperdrive Pearl

Roto Grip U-R1 Pearl Reactive

Medium to heavy oil

Sale price $169.95 Regular price $289.95In stock
Radical Snapshot Bowling Ball

Radical Snapshot

Radical HK22C+ Pearl Reactive

Medium oil

Sale price $89.95 Regular price $259.95In stock

Balls with the Roto Grip RST Core

None of the 11 balls with the Roto Grip RST Core are in stock at BowlersMart right now.

Show 11 balls no longer available at BowlersMart
More bowling balls with the Roto Grip RST Core
Ball Cover First seen
Roto Grip RST Black Bowling Ball Roto Grip eTrax ULTRA Pearl Reactive November 2025
Roto Grip RST X-1 Bowling Ball Roto Grip MicroTrax Hybrid Reactive October 2020
Roto Grip RST X-1 Squad Overseas Bowling Ball Roto Grip eTrax Pearl Reactive April 2021
Roto Grip RST X-2 Bowling Ball Roto Grip eTrax Plus Pearl Reactive June 2021
Roto Grip RST X-2 Squad Overseas Bowling Ball Roto Grip MicroTrax Solid Reactive June 2022
Roto Grip RST X-2 Pro Overseas Bowling Ball Roto Grip Hyper Response Pearl Reactive June 2024
Roto Grip RST X-3 Bowling Ball Roto Grip MicroTrax Hybrid Reactive June 2022
Roto Grip RST X-3 Squad Overseas Bowling Ball Roto Grip MicroTrax Solid Reactive December 2022
Roto Grip RST X-4 Overseas Bowling Ball Roto Grip MicroTrax Pearl Reactive June 2024
Roto Grip RST X-3 Pro Overseas Bowling Ball Roto Grip XtremeTrax Reactive October 2023
Roto Grip RST Crash Overseas Bowling Ball Roto Grip OptiTrax Solid Reactive January 2024

Where the Roto Grip RST sits

Each dot is a core in balls we stock. Cores close together roll alike; the cover and layout decide the rest.

DV8 Larceny Core, RG 2.471, diff 0.028DV8 Renegade Core, RG 2.499, diff 0.040Track I-Core Gen4, RG 2.480, diff 0.053Brunswick Vintage Light Bulb Low RG Core, RG 2.568, diff 0.032Brunswick Dual Centric Core, RG 2.509, diff 0.047Ebonite Big Time Core, RG 2.500, diff 0.054Hammer Stacked LED Core, RG 2.545, diff 0.047Hammer Vindicator Core, RG 2.474, diff 0.053Radical Vexed Variant Asymmetric Core, RG 2.490, diff 0.045Radical Modified Intel Symmetric Core, RG 2.483, diff 0.032Motiv Affliction V2 Core, RG 2.480, diff 0.055900 Global Conduit A.I. Core, RG 2.590, diff 0.050Roto Grip GEM A.I. Core, RG 2.490, diff 0.057Hammer Obsession Tour, RG 2.469, diff 0.034Hammer Gas Mask Core, RG 2.500, diff 0.058Ebonite Turbo Core, RG 2.510, diff 0.040Ebonite Centrex Symmetrical Mass Bias, RG 2.460, diff 0.056Motiv Excel Core, RG 2.550, diff 0.030Motiv Detonator Core, RG 2.470, diff 0.055Storm Solarion AI Core, RG 2.480, diff 0.054SWAG Insanity Symmetric Core, RG 2.520, diff 0.034SWAG Fusion Symmetric Core, RG 2.540, diff 0.036SWAG Watcher Symmetric Core, RG 2.510, diff 0.048SWAG Dragon Asymmetric Core, RG 2.480, diff 0.054SWAG Executioner Asymmetric Core, RG 2.500, diff 0.051Motiv Predator V2 Core, RG 2.470, diff 0.054Storm C3 Centripetal Control Core, RG 2.490, diff 0.029Roto Grip Rondure MaxD Core, RG 2.500, diff 0.058Hammer Vibe Core, RG 2.510, diff 0.042Brunswick Alert Core, RG 2.478, diff 0.037Brunswick Rampart Core, RG 2.502, diff 0.051DV8 Collision Core, RG 2.462, diff 0.052Track MC2 Asym Core, RG 2.470, diff 0.046Radical Evil Eye Symmetric Core, RG 2.490, diff 0.046Ebonite Iron Fist V2 Core, RG 2.470, diff 0.053Radical No Doubt Symmetric Core, RG 2.480, diff 0.051Storm Surge Core, RG 2.580, diff 0.024Roto Grip Hyped UP Core, RG 2.500, diff 0.042Roto Grip Morph-Wing Core, RG 2.510, diff 0.051Brunswick Fury Core, RG 2.524, diff 0.038Motiv Sigma Core, RG 2.470, diff 0.047Roto Grip Hustle Core, RG 2.530, diff 0.030900 Global Blast AI Core, RG 2.470, diff 0.055900 Global Strobe AI Core, RG 2.510, diff 0.052Radical Guru Core, RG 2.500, diff 0.044Track I-CORE 3.0, RG 2.480, diff 0.056DV8 Unholy Core, RG 2.500, diff 0.051Storm Catalyst Core, RG 2.500, diff 0.052Hammer Gauntlet Core, RG 2.501, diff 0.050Hammer Raw Hammer Core, RG 2.537, diff 0.038Storm Atmos A.I. Core, RG 2.530, diff 0.042Storm Booster Core, RG 2.540, diff 0.046Track Shuttle Core, RG 2.490, diff 0.038Brunswick Light Bulb Core, RG 2.524, diff 0.030Radical Sneak Attack Core, RG 2.540, diff 0.036Motiv Gear Core, RG 2.480, diff 0.034Hammer Huntsman Core, RG 2.470, diff 0.050Hammer Super LED Core, RG 2.632, diff 0.034Ebonite Enhanced V2 Core, RG 2.480, diff 0.048DV8 Dualistic Core, RG 2.490, diff 0.045Radical Vexed Asymmetric Core, RG 2.490, diff 0.036Motiv Quadfire Core, RG 2.550, diff 0.043Track Stealth Core, RG 2.480, diff 0.056Brunswick Tiered Hexagon Core, RG 2.540, diff 0.045Columbia 300 Piranha Core, RG 2.550, diff 0.043Storm Torsion AI Core, RG 2.470, diff 0.050Storm Element Max AI Core, RG 2.470, diff 0.055Storm Radius Core, RG 2.610, diff 0.020Roto Grip Rondure Tour X Core, RG 2.480, diff 0.034SWAG Unreal Core, RG 2.510, diff 0.047SWAG Craze Core, RG 2.520, diff 0.030SWAG Serpent Asymmetric Core, RG 2.510, diff 0.048Radical Torpedo Asymmetric Core, RG 2.480, diff 0.054Motiv Overload, RG 2.480, diff 0.050DV8 Duality Core, RG 2.480, diff 0.036Hammer Spheroid Core, RG 2.480, diff 0.048Radical Outer Limits Asymmetric, RG 2.490, diff 0.051Brunswick Danger Zone Core, RG 2.501, diff 0.048Storm RAD-TQ Core, RG 2.560, diff 0.051Storm Velocity Core, RG 2.480, diff 0.051Hammer LED Resin Bowling Ball Core, RG 2.586, diff 0.027Epic Spark Core, RG 2.540, diff 0.049Motiv Hadron Dual Density Core, RG 2.500, diff 0.045Track Criterion ID Core, RG 2.490, diff 0.047Brunswick Zone Asymmetric Core, RG 2.478, diff 0.048Ebonite Entity Core, RG 2.510, diff 0.052Roto Grip Rocker AI Core, RG 2.480, diff 0.050Motiv Flux Core, RG 2.570, diff 0.015DV8 Mantra Core, RG 2.490, diff 0.047Hammer Gas Mask Low Diff Core, RG 2.500, diff 0.034Motiv Impulse V2 Core, RG 2.550, diff 0.050SWAG APX V1 Core, RG 2.500, diff 0.042SWAG Fusion Core, RG 2.540, diff 0.036SWAG Judge Core, RG 2.490, diff 0.052900 Global Magna AI Core, RG 2.490, diff 0.044Roto Grip Rondure Core, RG 2.490, diff 0.052Columbia 300 Pulse PowerCOR, RG 2.460, diff 0.045Storm Element Tour A.I. Core, RG 2.470, diff 0.035KR Strikeforce KR Launch Core, RG 2.530, diff 0.047900 Global Ellipse Asymmetric A.I. Core, RG 2.480, diff 0.050Motiv Halogen Core, RG 2.550, diff 0.037Storm C3 + AI Core, RG 2.480, diff 0.031Motiv Gear APG, RG 2.470, diff 0.036Hammer High Rev Offset Core, RG 2.489, diff 0.053Hammer Huntsman Tour Core, RG 2.472, diff 0.036Hammer LED Core, RG 2.650, diff 0.015Storm Inverted Fe2 Core, RG 2.570, diff 0.046Storm Capacitor Core, RG 2.570, diff 0.022Storm Velocity A.I. Core, RG 2.470, diff 0.053Storm Atomic Core, RG 2.480, diff 0.053Storm RAD-X Asymmetric, RG 2.480, diff 0.054Storm ID AI Core, RG 2.510, diff 0.055Hammer FAB Asymmetric, RG 2.550, diff 0.051Columbia 300 Shifter Core, RG 2.470, diff 0.050Radical Modified Intel Symmetric, RG 2.480, diff 0.032Columbia 300 Columbia Ricochet Core, RG 2.480, diff 0.054Roto Grip Defense AI Core, RG 2.490, diff 0.053Storm Supercoil Core, RG 2.470, diff 0.053Storm Centripetal HD A.I. Core, RG 2.460, diff 0.056Hammer Modified Infamous Core, RG 2.567, diff 0.049Brunswick Ethos Core, RG 2.480, diff 0.053Hammer Hazmat Core, RG 2.470, diff 0.055Track Criterion MD Core, RG 2.500, diff 0.052Storm Ignition Core, RG 2.490, diff 0.052Roto Grip Momentous A.I. Core, RG 2.480, diff 0.049Brunswick Portal X Core, RG 2.473, diff 0.054Ebonite Emerge Core, RG 2.510, diff 0.053Radical Katana Core, RG 2.500, diff 0.050900 Global Meditate LD Symmetric Core, RG 2.560, diff 0.027Columbia 300 Movement Core, RG 2.510, diff 0.053Hammer Super Offset Core (pictured: Hammer Zero Mercy Solid Bowling Ball)1Brunswick Infinity Core (pictured: Brunswick Infinity Quest Bowling Ball)2Motiv Apex Predator Core (pictured: Motiv Apex Jackal Bowling Ball)3Roto Grip RST Core + AI (pictured: Roto Grip RST Hyperdrive Bowling Ball)4Hammer Aftermath Core (pictured: Hammer Fallout Bowling Ball)5Radical Snapshot Symmetric Core (pictured: Radical Snapshot Bowling Ball)6Roto Grip RST Core (pictured: Roto Grip RST Black Bowling Ball)EARLY REV-UPMID-LANELATER REV-UPHIGH FLAREMEDIUMLOW FLARE2.442.482.522.562.602.642.680.0100.0200.0300.0400.0500.060RG at 15 lbDifferential at 15 lb← Revs up soonerRevs up later →More flare ↑Less flare ↓

Nearest cores, zoomed in

Hover or tap a dot for that core’s numbers. Click a dot to open its page. Drag to move around when zoomed in. The same RG and differential do not guarantee the same ball motion.

Same family: Roto Grip RST Core + AI

This core 1 Nearest cores Other cores

Nearest cores to the Roto Grip RST Core
Core Brand Shape RG Diff vs this core
Hammer Zero Mercy Solid Bowling Ball1Hammer Super Offset CorePictured: Hammer Zero Mercy Solid
 Hammer Asymmetric 2.524 0.053 RG −0.006 · Diff 0.000
Brunswick Infinity Quest Bowling Ball2Brunswick Infinity CorePictured: Brunswick Infinity Quest
 Brunswick Asymmetric 2.521 0.051 RG −0.009 · Diff −0.002
Motiv Apex Jackal Bowling Ball3Motiv Apex Predator CorePictured: Motiv Apex Jackal
 Motiv Asymmetric 2.520 0.055 RG −0.010 · Diff +0.002
Roto Grip RST Hyperdrive Bowling Ball4Roto Grip RST Core + AIPictured: Roto Grip RST Hyperdrive
 Roto Grip Asymmetric 2.520 0.055 RG −0.010 · Diff +0.002
Hammer Fallout Bowling Ball5Hammer Aftermath CorePictured: Hammer Fallout
 Hammer Symmetric 2.520 0.052 RG −0.010 · Diff −0.001
Radical Snapshot Bowling Ball6Radical Snapshot Symmetric CorePictured: Radical Snapshot
 Radical Symmetric 2.520 0.050 RG −0.010 · Diff −0.003

Matches use 15 lb RG and differential.

Drilling and tools

Drilling layoutsLayout guides for symmetric and asymmetric ballsDual angle converterTurn a pin to PAP layout into a dual angle layout

Professional bowlers like to see continuous motion down lane with minimal deflection as the ball enters the pocket due to their rev rates usually being on the higher side. This logic was the basis of development by the R&D team as they looked to create a core that would maintain dynamics after drilling in order to maintain a higher level of core torque down lane. The larger mass at the base of the core does indeed create that. Especially since when drilled, the thumbhole will always end up near the bottom of the void area not to affect the bottom mass of the core all that much. Thus, making this core a “Tour Level” type core design.  

From Roto Grip’s description

Questions bowlers ask

What is the RG of the Roto Grip RST Core?

At 15 lb the Roto Grip RST Core has an RG of 2.530. It ranges from 2.520 to 2.590 across the listed weights.

What is the 14 lb RG of the Roto Grip RST Core?

At 14 lb the RG is 2.550.

What is the differential of the Roto Grip RST Core?

At 15 lb the differential is 0.053. The mass bias is 0.016.

Which bowling balls use the Roto Grip RST Core?

Roto Grip RST Black Bowling Ball, Roto Grip RST X-1 Bowling Ball, Roto Grip RST X-1 Squad Overseas Bowling Ball, Roto Grip RST X-2 Bowling Ball, Roto Grip RST X-2 Squad Overseas Bowling Ball. 0 are in stock now.

Can I still buy a ball with the Roto Grip RST Core?

Balls with this core are currently unavailable at BowlersMart. Closest in-stock alternatives by RG and differential include Hammer Zero Mercy Hybrid Bowling Ball, Hammer Fallout Bowling Ball, Brunswick Infinity Quest Pearl Bowling Ball, Motiv Apex Jackal Bowling Ball, Roto Grip RST Hyperdrive Pearl Bowling Ball, Radical Snapshot Bowling Ball.

How do the Roto Grip RST Core specs change by weight?

At 16 lb: RG 2.520, differential 0.049, mass bias 0.015. At 12 lb: RG 2.590, differential 0.029, mass bias 0.008.

How does the Roto Grip RST Core compare with my ball?

Type the ball you throw into the Compare with your ball box on this page. It shows the RG and differential side by side and saves your bag for every core page.

Sources and method

Specs. Roto Grip published specs, as shown on BowlersMart’s original Roto Grip RST core page (2022), as published by the manufacturer.

Baseline. The baseline is 265 in-stock, published reactive and urethane balls. Plastic and polyester covers, 2-piece, 3-piece and pancake cores, missing covers and missing RG or differential values are excluded.

Percentiles. Percentiles are the share of baseline balls with a strictly lower or higher value; ties are not counted.

Nearest cores. Nearest cores are ranked by distance on standardized 15 lb RG and differential, with the same symmetric or asymmetric shape preferred among near ties (distance bands of 0.1).

Mass bias. Mass bias is compared among asymmetric balls with numeric mass bias only.

Updated. Catalog and page updated 2026-10-16.

Next lesson

Compare cores by RGEvery in-stock ball from lowest to highest RGCompare cores by differentialEvery in-stock ball from lowest to highest differentialAll bowling ball coresCore libraries for every brand we carryRoto Grip core libraryEvery Roto Grip core we have specs for