Bowling ball core · Hammer

Hammer 40 Watt Core

Symmetric Hammer core

A symmetric core with mid-lane rev-up and medium flare, built for medium to heavy oil. Balls with this core are no longer available at BowlersMart.

  • Symmetric
  • RG 2.520
  • Diff 0.041
Hammer 40 Watt symmetric core shape inside the ball

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Specs

RG AT 15 LB

2.520

Mid-lane rev-up

Revs soonerRevs later

61% of the reactive and urethane balls we stock have a lower RG.

DIFFERENTIAL AT 15 LB

0.041

Medium flare

Less flareMore flare

36% of the reactive and urethane balls we stock have a lower differential.

MASS BIAS AT 15 LB

None

Symmetric core

Symmetric cores have no mass bias marker to place when drilling.

RG How soon the ball revs up.Differential How much the ball can flare.Mass bias How asymmetric the core is.
Hammer 40 Watt Core specs by ball weight
Weight RG DifferentialDiff Mass biasMB
16 lb 2.550 0.040 None
15 lbUsed on this page 2.520 0.041 None
14 lb 2.530 0.034 None
13 lb 2.560 0.030 None
12 lb 2.630 0.025 None

Source: Hammer published specs, as shown on BowlersMart’s original Hammer 40 Watt 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 Hammer 40 Watt?

Balls with the Hammer 40 Watt Core are no longer available at BowlersMart. These in-stock balls have the closest RG and differential.

Ebonite Turbo X Pearl Bowling Ball

Ebonite Turbo X Pearl

Ebonite HK22 GB 10.7 Pearl Reactive

Light to medium oil

Sale price $149.95 Regular price $229.95In stock
Storm Monsoon Bowling Ball

Storm Monsoon

Storm Reactor Solid

Medium oil

Sale price $139.95 Regular price $209.95In stock
Hammer Deep Ocean Vibe Bowling Ball

Hammer Deep Ocean Vibe

Hammer HK22 CT Reactive Plus

Light to medium oil

Sale price $129.95 Regular price $199.95In stock
Brunswick Fury Emerald Black Bowling Ball

Brunswick Fury Emerald Black

Brunswick PowerKoil 26 Hybrid Reactive

Dry to medium oil

Sale price $109.95 Regular price $179.95In stock
Hammer Raw Hammer Black Grey Bowling Ball

Hammer Raw Hammer Black Grey

Hammer Juiced Solid Reactive

Dry to medium oil

Sale price $99.95 Regular price $169.95In stock
Roto Grip hyped UP! Bowling Ball

Roto Grip hyped UP!

Roto Grip V-R1 Hybrid Reactive

Medium oil

Sale price $129.95 Regular price $179.95In stock

Balls with the Hammer 40 Watt Core

None of the 3 balls with the Hammer 40 Watt Core are in stock at BowlersMart right now.

Show 3 balls no longer available at BowlersMart
More bowling balls with the Hammer 40 Watt Core
Ball Cover First seen
Hammer Flawless Bowling Ball Hammer Juiced Pearl Reactive December 2018
Hammer Ruthless Bowling Ball Hammer Juiced Solid Reactive August 2019
Hammer Flawless Hybrid Bowling Ball Hammer Juiced Hybrid Reactive December 2019

Where the Hammer 40 Watt sits

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

Storm Element Tour A.I. Core, RG 2.470, diff 0.035DV8 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 2.508, 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 Core, RG 2.469, diff 0.034Hammer Super Offset Core, RG 2.524, diff 0.053Hammer Gas Mask Core, RG 2.500, diff 0.058Ebonite Centrex Symmetrical Mass Bias Core, RG 2.466, diff 0.056Motiv Excel Core, RG 2.550, diff 0.030Motiv Detonator Core, RG 2.470, diff 0.055Storm Solarion A.I. Core, RG 2.480, diff 0.054SWAG Insanity Symmetric Core, RG 2.520, diff 0.034SWAG Fusion Core, RG 2.540, diff 0.036SWAG Watcher Symmetric Core, RG 2.510, diff 0.048SWAG Dragon Asymmetric Core, RG 2.490, diff 0.050SWAG 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 Aftermath Core, RG 2.520, diff 0.052Brunswick 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 2.473, diff 0.046Radical Evil Eye Symmetric Core, RG 2.495, diff 0.046Ebonite Iron Fist V2 Core, RG 2.473, diff 0.053Radical No Doubt Symmetric Core, RG 2.485, diff 0.051Storm Surge Core, RG 2.580, diff 0.024Roto Grip Morph-Wing Core, RG 2.510, diff 0.051Motiv Sigma Core, RG 2.470, diff 0.047Roto Grip Hustle Core, RG 2.530, diff 0.030900 Global Blast A.I. Core, RG 2.470, diff 0.055900 Global Strobe A.I. Core, RG 2.510, diff 0.052Radical Guru Core, RG 2.503, diff 0.044Track I-CORE 3.0, RG 2.486, diff 0.056DV8 Unholy Core, RG 2.504, diff 0.051Brunswick Infinity Core, RG 2.521, diff 0.051Storm Catalyst A.I. Core, RG 2.480, diff 0.053Hammer Gauntlet Core, RG 2.501, diff 0.050Storm Booster Core, RG 2.540, diff 0.046Track Shuttle Core, RG 2.480, diff 0.040Brunswick Light Bulb Core, RG 2.524, diff 0.030Radical Sneak Attack Core, RG 2.544, 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 2.496, diff 0.045Radical Vexed Asymmetric Core, RG 2.498, diff 0.036Motiv Quadfire Core, RG 2.550, diff 0.043Track Stealth Core, RG 2.482, diff 0.056Brunswick Tiered Hexagon Core, RG 2.540, diff 0.045Columbia 300 Piranha Core, RG 2.554, diff 0.043Storm Torsion A.I. Core, RG 2.470, diff 0.050Storm Element Max A.I. 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 0.052Motiv Overload Core, 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 Core, RG 2.499, diff 0.051Motiv Apex Predator Core, RG 2.520, diff 0.055Brunswick 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 Modified LED 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 2.496, diff 0.047Brunswick Zone Asymmetric Core, RG 2.478, diff 0.048Ebonite Entity Core, RG 2.515, diff 0.052Roto Grip Rocker A.I. Core, RG 2.480, diff 0.050Motiv Flux Core, RG 2.570, diff 0.015DV8 Mantra Core, RG 2.498, diff 0.047Hammer Gas Mask Low Diff Core, RG 2.500, diff 0.034Roto Grip RST A.I. Core, RG 2.520, diff 0.055Motiv Impulse V2 Core, RG 2.550, diff 0.050SWAG APX V1 Core, RG 2.500, diff 0.042SWAG Judge Core, RG 2.490, diff 0.052900 Global Magna A.I. Core, RG 2.490, diff 0.044Columbia 300 Pulse PowerCOR Core, RG 2.468, diff 0.045KR Strikeforce 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 A.I. Core, RG 2.480, diff 0.031Motiv Gear APG Core, RG 2.470, diff 0.036Radical Snapshot Symmetric Core, RG 2.523, diff 0.050Hammer 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 0.022Ebonite Turbo Core (pictured: Ebonite Turbo X Bowling Ball)1Storm Atmos A.I. Core (pictured: Storm Typhoon Bowling Ball)2Hammer Vibe Core (pictured: Hammer Arctic Vibe Bowling Ball)3Brunswick Fury Core (pictured: Brunswick Fury Emerald Black Bowling Ball)4Hammer Raw Hammer Core (pictured: Hammer Raw Hammer Pearl Blue Silver White Bowling Ball)5Roto Grip Hyped UP Core (pictured: Roto Grip hyped UP! Bowling Ball)6Hammer 40 Watt Core (pictured: Hammer Flawless Hybrid 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.

This core 1 Nearest cores Other cores

Nearest cores to the Hammer 40 Watt Core
Core Brand Shape RG Diff vs this core
Ebonite Turbo X Bowling Ball1Ebonite Turbo CorePictured: Ebonite Turbo X
 Ebonite Symmetric 2.517 0.040 RG −0.003 · Diff −0.001
Storm Typhoon Bowling Ball2Storm Atmos A.I. CorePictured: Storm Typhoon
 Storm Symmetric 2.530 0.042 RG +0.010 · Diff +0.001
Hammer Arctic Vibe Bowling Ball3Hammer Vibe CorePictured: Hammer Arctic Vibe
 Hammer Symmetric 2.510 0.042 RG −0.010 · Diff +0.001
Brunswick Fury Emerald Black Bowling Ball4Brunswick Fury CorePictured: Brunswick Fury Emerald Black
 Brunswick Symmetric 2.524 0.038 RG +0.004 · Diff −0.003
Hammer Raw Hammer Pearl Blue Silver White Bowling Ball5Hammer Raw Hammer CorePictured: Hammer Raw Hammer Pearl Blue Silver White
 Hammer Symmetric 2.537 0.038 RG +0.017 · Diff −0.003
Roto Grip hyped UP! Bowling Ball6Roto Grip Hyped UP CorePictured: Roto Grip hyped UP!
 Roto Grip Symmetric 2.500 0.042 RG −0.020 · Diff +0.001

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

The 40 Watt core was named after its light bulb shape and differential in the forties. You can expect medium flare potential from this core.

From Hammer’s description

Questions bowlers ask

What is the RG of the Hammer 40 Watt Core?

At 15 lb the Hammer 40 Watt Core has an RG of 2.520. It ranges from 2.520 to 2.630 across the listed weights.

What is the 14 lb RG of the Hammer 40 Watt Core?

At 14 lb the RG is 2.530.

What is the differential of the Hammer 40 Watt Core?

At 15 lb the differential is 0.041. This is a symmetric core, so mass bias is not applicable.

Which bowling balls use the Hammer 40 Watt Core?

Hammer Flawless Bowling Ball, Hammer Ruthless Bowling Ball, Hammer Flawless Hybrid Bowling Ball. 0 are in stock now.

Can I still buy a ball with the Hammer 40 Watt Core?

Balls with this core are currently unavailable at BowlersMart. Closest in-stock alternatives by RG and differential include Ebonite Turbo X Pearl Bowling Ball, Storm Monsoon Bowling Ball, Hammer Deep Ocean Vibe Bowling Ball, Brunswick Fury Emerald Black Bowling Ball, Hammer Raw Hammer Black Grey Bowling Ball, Roto Grip hyped UP! Bowling Ball.

How do the Hammer 40 Watt Core specs change by weight?

At 16 lb: RG 2.550, differential 0.040. At 12 lb: RG 2.630, differential 0.025.

How does the Hammer 40 Watt 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. Hammer published specs, as shown on BowlersMart’s original Hammer 40 Watt core page (2022), as published by the manufacturer.

Baseline. The baseline is 212 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 2026-10-17.

Next lesson

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