• AMF
  
• Dyno-Thane
  
• Roto-Grip
  
• Storm
  
• Track
  
• Brunswick
  
• Brunswick Asymmetrical
• Brunswick Symmetrical
• Columbia
  
• Ebonite
  
• Ebonite Asymmetrical
  
• Ebonite Symmetrical
  
• Mass Bias
• Pro-Pin
  
• Pro-CG
  

Drilling Pattern # 2

• Locate the mass bias and mark it with an 'MB.'
• Place the major pin 4-1/4" from the player's PAP and locate the mass bias (MB) along the player's perpendicular axis line (PAL).
• This layout will most often require an extra hole, so place this hole on the PAP and remove excess side weight to '0.'
• This layout works well to produce medium length and heavy midlane roll.
• Usually works well on medium to heavy oil, especially longer oil patterns.

Drilling Pattern # 3

• Locate the mass bias and mark the spot with an 'MB.' Remember, the mass bias is a fine tuning device used by advanced players.
• Place the major pin 3-3/8" from the PAP and locate the mass bias halfway between the player's ball track and PAL.
• Place the extra hole, if necessary, on the player's PAP, removing excess side weight to less than an ounce.
• NOTE: This is a "High Flare" layout and should only be used by low rev players seeking maximum ball reaction!
• This layout is ideal for long/or heavy oil conditions for when you need the ball to break into a hook earlier than your other equipment.

Drilling Pattern # 4

• For this layout, we will select a ball with a pin distance of 2.5" from the CG.
• Place the major pin 1-1/2" from the PAP. Remember to keep the pin along the line located between the PAP and the player's finger holes.
• Place the mass bias in the player's track.
• Check side weight to see if an extra hole is necessary. If so, place the hole on the PAP.
• This layout will produce heavy roll with a controllable backend reaction. Players with extensive side roll or high rev players will love this layout to help control dry, short oil patterns with very dry backends.

Asymmetric Core Drilling Instructions

The following instructions are 6 basic layouts for different bowlers styles and lane conditions. These are by no means the only drilling layouts. You may combine any desired flare-safe pin position with any BOMB location. BOMB location determines the shape of the breakpoint and backend hook. Zero degrees promotes an earlier, smoother breakpoint, 45 degrees creates a medium length and stronger backend hook, 90 degrees provides more length with a smooth breakpoint, and BOMBs on the negative side of the ball track provide a hook/set backend reaction. The pin distance from the PAP determines the amount of track flare and is the major determinant of hook potential. The Center of Gravity (CG) will generally fall in line with the pin and the BOMB, but may be slightly to the left or the right. The CG is not influential in the ball s reaction.

The following illustrations are based on a PAP of 5 inches across and 1 inch up from the center of span. The actual pin location in reference to the center of the span may vary depending on your PAP coordinates. Left hand drillings will be a mirror image of the illustrations.

Cleaning and Maintenance:
Consistent performance and longevity are the by-products of a strict maintenance regimen. We recommend cleaning your ball after each league with a strong degreasing cleaner to remove oil and dirt from the ball s surface and to reduce the amount of oil absorbed into the ball. Alcohol and glass cleaners are not effective at breaking down lane oil. We suggest the Powerhouse Energizer or Powerhouse Ball Scrubs, both biodegradable, citrus based degreasing agents.

You will also need to periodically refresh the ball s surface texture to maintain consistency of breakpoint length and backend hook. All particle balls need more maintenance than reactive resin. The frequency will be determined by the amount of games bowled and the lane conditions.

Drilling Pattern #1 | Drilling Pattern #2 | Drilling Pattern #3 | Drilling Pattern #4 |

Drilling Pattern #5 | Drilling Pattern #6 |

Drilling Pattern # 1
4" Pin 90° BOMB

• Ball Choice: Pin out 1 to 2 1/2", all top weights
• Reaction: Medium length, smoother breakpoint, continuous arc
• Suitable for: Medium to heavy oil, dry backends, drier outsides, slower ball speeds, higher RPM players
• Flare Potential: Medium high
• Pin Placement: 4" from bowler s PAP, located on a line from the PAP to the ring finger. If PAP is not known, place pin next to ring finger
• BOMB Placement: In, or near, the thumbhole (approximately 5 1/2" from the PAP)
• Balance Hole: None needed. If an earlier breakpoint is needed, place hole on PAP and drill back to 1/2 oz. negative side weight

Drilling Pattern # 2
4" Pin/ 45° BOMB Rev Leverage

• Ball Choice: Pin out 3 to 5", all top weights
• Reaction: Earliest breakpoint, maximum hook potential in heavier oil
• Suitable for: Longer oil patterns, oil carrydown, faster ball speeds
• Flare Potential: High
• Pin Placement: 4" from bowler s PAP, located below the ring finger. If PAP is not known, place pin below the ring finger
• BOMB Placement: 4:30 direction from the pin, in the positive/thumb quadrant. (approximately 3" from the PAP)
• Balance Hole: Lower track players or low to medium Rpm s: Drill balance hole into the locator pin to a depth of 2 1/2" to 3", ending with 1/2 oz. negative side weight
• Higher track players or high Rpm s: Drill balance hole into the BOMB logo to a depth of 2 1/2 to 3", ending with 1/2 oz. negative side weight.

Drilling Pattern # 3
5" Pin/ 0° BOMB

• Ball Choice: Pin out 1 to 3", up to 2 3/4 oz. top weight
• Reaction: Medium length, strong breakpoint
• Suitable for: Medium to high ball speeds, higher RPM players
• Flare Potential: Medium high
• Pin Placement: 5" from bowler s PAP, located beneath the fingers. If PAP is not known, place pin under the bridge.
• BOMB Placement: On the PAP
• Balance Hole: Lower track players or low to medium RPM s: Drill balance hole into the locator pin, back to 1/2 oz. positive side weight.
• Higher track players or high RPM s: Drill balance hole into the BOMB, back to 1/2 oz. positive side weight.

Drilling Pattern # 4
5 1/2" Pin Above/ 45° BOMB

• Ball Choice: Pin out 3 to 5", all top weights
• Reaction: Delayed reaction, strong breakpoint
• Suitable for: Slower ball speeds, shorter oil patterns
• Flare Potential: Medium
• Pin Placement: 5 1/2" from bowler s PAP, located above the fingers. If PAP is not known, place pin over the bridge.
• BOMB Placement: To the right of the center of grip (approximately 2 1/2" from the PAP)
• Balance Hole: Drill balance hole into the PAP, back to 1/2 oz. positive side weight.

Drilling Pattern # 5
Pin Axis/5" BOMB

• Ball Choice: All pin outs, all top weights
• Reaction: Early roll, smooth, arcing backend hook style
• Suitable for: Wet/dry or over-reacting lane conditions
• Flare Potential: Low
• Pin Placement: On the bowler s PAP
• BOMB Placement: Under the fingers
• Balance Hole: If needed, place 2 inches past the bowler s PAP, back to 1/2 oz. positive side weight

Drilling Pattern # 6
Full Roller

• Ball Choice: All pin-out distances, all top weights
• Reaction: Early breakpoint, strong arc backend hook style
• Suitable for: Full rollers
• Flare Potential: High
• Pin Placement: 3 3/8" from bowler s center of span, located in an 8:00 direction from the center of span. (For more length and less flare, place pin 2 inches from the bowler s center of span)
• BOMB Placement: 1 5/8" from the bowler's center of span, located in a 2:00 direction from the center of span
• Balance Hole: If needed, place 6" from center of span in a 2:00 direction to remove excess positive side weight, 6" from the center of span in an 8:00 direction to remove excess negative side weight
• Drilling #6 Full Roller Ball Track 3 3/8" Pin/0° BOMB

Columbia Drilling Intrustions

Images shown for right-hander. Left-hander is reversed. All drill patterns for bowling balls are customized for each individual bowler by starting with the bowlers' Positive Axis Point (PAP). The positive axis point is the point on the ball that the ball initially rotates about. It can be found by finding the point on the ball that is equal distance from the bowler's initial ball track (before the ball flares). This is the first oil ring on the ball and is the one closest to the thumbhole. For a 3/4 roller (ball track just outside of the fingers and thumb), the PAP is approximately 5 inches over along the midline and 1/2 inches up along the vertical axis line. This can be verified by placing a piece of tape on the ball at the PAP. Have a friend observe your bowling.





When the ball first comes off your hand and contacts the lane, the tape should spin without moving around the ball. It should appear stationary if it is on the PAP. Some adjustments might be necessary. A bowler cannot see this themselves. By the time they see the ball 10-12 feet past the foul line, the axis point has moves towards the preferred spin axis of the ball and they would get a false reading. A pro shop can find the PAP from the worn ball track on a ball but the best method is the one suggested here. Once the PAP is determined, it is time to select a drilling pattern to create the ball reaction the bowler desires.

Drilling patterns are techniques used to change the initial position of the core in the ball to alter its flare potential and distance it travels down the lane before it starts to hook. Generally, more flare is equated to more hook because it increases the friction. This is achieved by keeping a dry area of the ball in contact with the lane as opposed to an area of the ball, which has oil on the surface. The second ball to the right shows the flare potential and ball reaction.

The pin is the end of the core. By locating it at different distances from the PAP, we can create different motions in the same type of ball. The center of gravity (CG) is the heaviest point on the ball. Moving it to different locations has the same effect as moving the pin, but it has less impact. For example, if a ball is drilled with the pin at 3" and the CG at 1" from the PAP, it will have maximum flare from the pin position. But, it will start hooking earlier with an arcing break point due to the CG position.

Drilling Instructions for Different Bowling Styles