Chicago Pneumatic CP 4160 Rivet Busters (The "Hell Dog")

Chicago Pneumatic CP 4160 Rivet Busters (CPS) — “Hell Dog” / “Boyer Buster”

If you need a compact pneumatic rivet buster that hits like a much bigger breaker, the Chicago Pneumatic CP 4160 is built for that exact job. Originally designed for cutting and forming metal rivets, the CP buster has become a concrete-demolition workhorse and one of the standouts in the Chicago Pneumatic lineup. It delivers a low-frequency blow with impact energy often compared to a paving breaker twice its weight, which is why it’s earned jobsite nicknames like “Hell Dog” and “Boyer Buster.”

Built for concrete demolition without the “runaway tool” feel

Big demolition power is only useful if you can control it. The CP 4160 is designed to put heavy hitting power in your hands while staying controllable for real-world concrete and masonry work. Between the progressive (teasing) throttle and the Boyer valve design, the tool is engineered to deliver a strong, consistent blow that doesn’t feel erratic when you’re working an edge, chasing a crack, or breaking tight areas.

CPS Control Power System: safety + wear control that protects the tool

The CP 4160 is part of the Rivet Busters with CPS (Control Power System) range, which adds practical protection where it counts. CPS includes a stepped piston and stepped cylinder to help prevent accidental ejection of the piston.

CPS also helps you avoid running the tool into expensive damage:

• A wear-indicating groove on the lower sleeve signals when the bumper is worn and needs replacement.
• When the bumper reaches heavy wear, CPS can open bleeding ports and stop the piston in a lower position—a built-in warning that it’s time to service wear parts before you damage sleeves or the cylinder.

Features & benefits (CP 4160 highlights)

• Teasing throttle for progressive hitting frequency—better control of a powerful buster
• Special Boyer valve that effectively lengthens the cylinder stroke for more hitting power
• Boyer valve design helps make the blow more consistent
• Forged steel handle for long life in rugged conditions
• Stepped piston (hardened steel) and stepped cylinder for safety and durability
• New buffer ring specified as 90 durometer rubber for extended life
• 1/2" inlet bushing for serious airflow delivery
• Handle choices: open grip/outside trigger or D-handle/inside trigger
• Cylinder options referenced in the CPS buster line: 11" cylinder (720 bpm) or 8" cylinder (1080 bpm), depending on configuration

Choose your CP 4160 configuration (P vs D)

1. CP 4160 P (Open Grip / Outside Trigger)
   A classic open-handle feel for positioning and quick feathering—ideal if you like maximum freedom of hand placement.
2. CP 4160 D (D-Handle / Inside Trigger)
   A more enclosed grip style for users who prefer that control and hand position, especially in sustained chipping.

CP 4160 specs (at a glance)

CP 4160 P (Open Grip)

• Weight: 24 lb
• Blows per minute: 1100 bpm
• Cylinder stroke: 6 in
• Length: 20.5 in
• Air consumption: 44 cfm
• Air inlet: 1/2 in
• Chuck size: 11" Jumbo Shank
• Cylinder: Short cylinder

CP 4160 D (D-Handle)

• Weight: 25 lb
• Blows per minute: 1100 bpm
• Cylinder stroke: 6 in
• Length: 20.5 in
• Air consumption: 44 cfm
• Air inlet: 1/2 in
• Chuck size: 11" Jumbo Shank
• Cylinder: Short cylinder

Air system notes that matter on demolition tools

Chicago Pneumatic rivet busters are designed to work with “Jumbo” shank steels, and your air quality matters. Using a water separator and an inline lubricator helps performance and extends tool life by reducing premature wear—especially in high-use demolition environments.

Recommended wear items & accessories to keep on hand

To keep a CP 4160 running hard (and avoid downtime), it’s smart to stock the wear parts that take the abuse:

• Bumpers
• Sleeves
• Retainer spring
• Whip hose

Support items commonly paired with CPS rivet busters include air swivels, whip hoses, inline lubricators, a water separator, and Chicago Pneumatic tool oil for daily upkeep.