The Boss Shotshells Mk III Shotshell Tester is a rugged, handheld device engineered to quickly and accurately identify the shot composition inside a loaded shotshell. Whether you’re enforcing compliance in the field or verifying loads on the bench,
the Mk III uses electrical conductivity to determine shell contents with precision.
A simple contact test delivers results through audible, tactile, and visual outputs so you get immediate, unmistakable feedback in any environment. Conductive materials like Steel, Copper, and Tungsten generate strong signals. Lead, with its lower conductivity, triggers a weak response. Bismuth, being nearly non-conductive, produces no output, providing a clear distinction between non-toxic and toxic shot. Compact. Accurate. Built for the Field. The Boss Mk III gives law enforcement officials the confidence to verify factory loaded shotshell content on demand, no guesswork.
ON/OFF button and speaker cover
LED light
Runs on a 9V battery
1. Powering On and Off
A. Turn ON
Momentarily press the black ON/OFF button, located between the LCD display and the orange speaker cover.
The LED light and LCD display will illuminate.
Upon startup, the unit will resume the output mode last used before shutdown.
To toggle output modes (audible only, tactile only, or both), repeatedly press the ON/OFF button.
B. Turn OFF
Press and hold the ON/OFF button until the LED and LCD display turn off.
2. Shotshell Inspection
Important: Ensure there are no metal
objects (e.g., rings, watches, bracelets) within 3” of the orange region of the device during testing. Metal interference may cause false readings.
A. Confirm the LCD & LED
Confirm the LCD display and LED light are illuminated.
Note: For .410 shells, place the shell into the 0.500” diameter hole located in the center of the receptacle.
C. Read the Output
Once the shell is in place, observe the LCD display.
A bar graph will appear, indicating the shot type based on the reference scale adjacent to the screen.
B. Insert the Shotshell – Make sure no metal objects are within 3” of the orange region of the device during testing. (E.g. rings, watches, etc. or false readings will occur.)
The test receptacle is designed to accept 10 Gauge through .410 shotshells.
Inside the receptacle are detents for
precise positioning:
- 10 GA
- 12 GA / 16 GA
- 20 GA / 28 GA
- .410
Insert the crimped end of the shotshell into the appropriate detent so that it sits flush with the bottom of the receptacle.
Note:
A full signal typically indicates Steel, Copper, or Tungsten (non-toxic). A weaker signal may indicate Lead (toxic). If there is no visual or audible response, this indicates Bismuth, which is less conductive than lead and non-toxic.
For shells with head brass taller than 16mm, steel in the head brass may interfere with the reading. To compensate, follow the standard testing procedure as described above, then subtract one bar from the LCD display to obtain the accurate result.
Legal Disclaimer & Warranty Information
Product: Boss Shotshells Mk III
Shotshell Tester
Manufacturer: Boss Shotshells
Phone: 877-410-BOSS (2677)
Website: BossShotshells.com
Disclaimer of Use and Limitations
The Mk III Shotshell Tester is designed solely as a supplemental tool to assist in identifying the metal composition of shotgun pellets. Due to the wide variety of commercially available ammunition and the evolving nature of shotshell construction, Boss Shotshells makes no guarantee that the Mk III will accurately detect or identify all types of shot or payload materials under all circumstances. This tool should not be solely relied upon for making legal decisions, including—but not limited to—citations, arrests, seizures, or prosecution. In cases where potential violations are detected using this device and the results are disputed, we strongly advise that the shell in question be submitted to a certified forensic laboratory for professional analysis. These facilities use highly specialized and calibrated equipment (e.g., XRF analyzers) capable of producing definitive results. By purchasing and/or using the Mk III Shotshell Tester, you agree to the following conditions:
No Refunds or Returns – All sales are final. Boss Shotshells will not issue refunds or accept returns under any circumstances, including false or inaccurate readings.
No Legal Testimony – Boss Shotshells and its representatives will not be summoned or required to appear in any court or legal proceeding to testify regarding the device’s accuracy, operation, or usage.
No Absolute Readings – The Mk III is not a laboratory-grade instrument and does not provide certified or absolute readings like professional XRF devices.
Waiver of Legal Claims – By using this product, you and/or any associated agency agree to waive all legal claims against Boss Shotshells, its owners, and employees. This includes, but is not limited to, claims involving false readings, personal injury, property damage, or loss of equipment. Assumption of Risk – You assume full responsibility and liability for the use of this product, including any consequences arising from its use.
Limited Warranty
Boss Shotshells warrants the Mk III Shotshell Tester to be free from defects in materials and workmanship under normal use for a period of 90 days from the original date of purchase.
What is Covered:
Manufacturing defects
Component failure under standard use
What is Not Covered:
Damage resulting from misuse, abuse, or neglect
Exposure to water, excessive moisture, or environmental extremes
Physical impact, tampering, or modification
Damage deemed by Boss Shotshells to fall outside of normal use conditions
This warranty is non-transferable and valid only to the original purchaser with proof of purchase. Warranty service will be provided at the sole discretion of Boss Shotshells and may include repair, replacement, or equivalent substitution of the product.
To request service under this warranty, contact:
Email: [email protected]