Gripper Rating Info > Rating Types > RGC

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RGC

RGC stands for Redneck Gripper Calibration, a repeatable method used to rate the closing resistance of torsion-spring hand grippers. A gripper is held in a fixture and weight is applied near the handle end until the handles touch. The minimum hanging load that produces closure is recorded as the gripper's RGC rating.[1]

Despite the original name, RGC is more accurately described as a rating than a formal calibration. It measures one gripper under a defined apparatus and procedure; it does not adjust the gripper to a standard and does not certify a person's hand strength.

What an RGC number means

An RGC value is the external load required to make that individual gripper close on the rating device. A gripper marked 150 RGC required approximately 150 pounds of hanging load under that rater's RGC procedure.

The number is useful for:

  • Comparing individual grippers across different brands
  • Identifying unusually easy or hard examples of one model
  • Building a training progression in smaller steps
  • Recording the strength of an unmarked or modified gripper
  • Distinguishing a manufacturer's model name from the tested specimen

RGC is not the pounds of force produced by the athlete's hand. The hand applies force through four fingers at changing positions and angles, while the rating device applies a controlled load at a specified point. The value is a comparative equipment measurement.

Basic rating process

An RGC-style rating generally follows this sequence:

  1. Secure one handle so the gripper cannot rotate or slide.
  2. Place a strap or loading attachment at the standard position near the end of the free handle.
  3. Add known weight until the handle ends touch.
  4. Reduce or refine the load to identify the lightest weight that consistently closes the gripper.
  5. Record the result, the rater and any relevant preparation or equipment details.

The strap position is important. Moving the load farther from or closer to the spring changes the leverage and therefore the number. Fixture geometry, strap thickness, when “closed” is judged, spring condition and test repetitions can also affect the result.

RGC versus manufacturer poundage

Manufacturer poundage is not standardized across brands. One company may estimate force at the middle of a handle, another may use a mathematical model, and another may simply assign numbers that order the product line. Cannon PowerWorks adopted RGC so different brands could be compared with one consistent test.[1]

For example, an RB 160 is a model name rather than a promise that the gripper will rate 160 RGC. Cannon PowerWorks lists the current RB 160 Chrome at an average near 95 RGC.[2] Similar differences occur throughout the gripper market.

Never convert a printed poundage directly into RGC without testing the specimen.

Individual variation

Two grippers of the same model can receive different RGC ratings. Relevant variables include:

  • Spring-wire diameter and material
  • Coil dimensions and spring temper
  • Handle spread
  • Spring mounting depth
  • Manufacturing tolerances
  • Spring seasoning and prior use
  • Rating apparatus and procedure

This variation is one reason collectors often record both the model and the individual rating. A result such as “CoC No. 3, 149 RGC” conveys more information than the model alone.

Precision and repeatability

Cannon PowerWorks reports whole-pound ratings and states that decimal precision is not justified by the method's practical margin of error. It identifies strap condition, strap placement, spring condition and the judgment of handle contact as contributing factors.[1]

Ratings from the same experienced rater and apparatus are usually the most directly comparable. Numbers from different raters can still be useful, but close results should not automatically be treated as meaningfully different unless their procedures agree. When preserving data, record:

  • RGC value and units
  • Rater or rating service
  • Date
  • Whether the gripper was new, seasoned, filed or otherwise modified
  • Apparatus or procedure when it differs from common practice

Ratings data and averages

A model average summarizes tested specimens; it does not guarantee the result of the next gripper. Cannon PowerWorks' ratings table contained more than 22,500 ratings as of its January 2026 update and publishes averages, modes, minimums, maximums and sample counts for many models.[1] Sample size should be considered when using those figures.

A single GripperVault entry likewise documents that submitted specimen, not every gripper of the same model. Both individual records and large datasets are valuable when their scope is stated clearly.

Video explanations

What is an RGC?

Demonstration of gripper rating

Both videos are presented by Jedd Johnson and demonstrate the concept and practical rating process.

External resources

References

  1. Cannon PowerWorks, "Gripper Strength Ratings Data," rating method, dataset scope and discussion of whole-pound precision. ↩
  2. Cannon PowerWorks, "RB 160 (Chrome)," example distinguishing an RB model name from its average RGC rating. ↩

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