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GaugeMate General

  • How do you test GaugeMate adapters ?

    We've got independent velocity test data from Sherman Bell.  We also have our own patterning data.

    The variety of break action shotguns made since the late -19th Century is daunting. Chamber dimensions weren’t standardized in England and Europe until 1902. Many guns were made with chambers shorter than 2 ¾”.

    Our approach has focused on trying the adapters in as many guns (old & new) as possible. We have had substantial assistance from members of the California Side by Side Society. From them we have borrowed Clabroughs, Horsleys, Darnes, Purdeys, Rigbys as well as many other makes.


  • What kind of patterns and Velocity does factory ammunition produce in GaugeMate adapters?


    We've got independent velocity test data from Sherman Bell.  We also have our own patterning data.

  • What kind of ammunition do you recommend?

    Remington STS and Winchester AA are the only types of ammunition we recommend. Hulls of lesser construction may bulge or stick.

  • Have GaugeMate adapters been proven in formal competition ?

    Dave Fjelline has successfully won various 20-28 competitions using his favorite 12-gauge gun with the help of GaugeMate adapters such as the National Sporting Clays Association U.S. Winter Open Championship.  He has been a supporter of GaugeMate adapters since being introduced to them back in 2005.

    Ken Nichols is a shooter that has just recently punched to A-class in July 2011 using 12-20, 12-28 and 28-410 GaugeMate adapters.

  • Have any shooting sports magazines reviewed your adapters?

    Check out our reviews.

  • How are GaugeMate adapters made ?

    They are precision machined from stainless steel to standards set by the Sporting Arms and Ammunition Manufactures Institute, Inc. (SAAMI). Custom adapters are made to standards set by the Commission Internationale Permanente pour l’Epreuve des Armes à Feu portatives (CIP).

  • Can I safely use GaugeMate adapters in Damascus barreled guns?

    Many Damascus barrels have been subject to modern nitro-proof testing. It is the users responsibility to insure that any gun used is safe for modern ammunition.

  • Can I use 3” 20-g ammunition in my 12 to 20-g adapters?

    No, they are designed for 2 ¾” ammunition.

  • Do you have adapters for magazine-fed/pump action guns?

    GaugeMate now has adapters for pump shotguns available!  Pocket Sportsman Pump

    These adapters will feed through a pump shotgun and have a special internal o-ring to retain the ammunition in the adapter when cycling through.

  • How does using GaugeMate adapters affect recoil ?

    Generally, it’s substantially reduced. For instance, 12-g ammo contains 1 or 1 1/8 -ounce of shot. If you use a 12 to 20-g adapter, then your 20-g ammo is probably loaded with 7/8-ounce of shot. Assuming the same Velocity, less weight of shot equals less recoil.

  • I have an over-under shotgun, will GaugeMate adapters fit?

    Yes.  Because our adapters are designed to fit the chamber specifications and not for any particular style or brand gun, they fit universally to any gun that is made to SAAMI specs.

  • Are GaugeMate adapters suitable for hunting?

    Absolutely !

  • Can I reload hulls that have been fired in split-adapters (10 to 12, 12 to 16, 16 to 20 and 20 to 28-g)?

    A qualified yes. This will depend on your chamber dimensions. Customers whose chambers are “tight” report minimal (or no) cutting of the hull.

  • Do your customers send you feedback ?

    Why yes... yes they do. Click here to read some of our customer feedback.  If you've got a comment or question we'd love to hear from you. Use our Contact Us email form.

  • Are any of your adapters rifled?

    Yes, our New Products for Pocket Armory are rifled, as well as our GaugeMate Platinum adapters for pistol/rifle.

    Our current line of cartridge adapters and all shotgun-shotgun adapters are smooth-bore.

  • Can you make custom adapters for my gun?

    Yes, we do offer custom services.  You can find custom shotgun to shotgun adapters on our GaugeMate Custom page.  You can also Contact Us directly about any other sizes that you may be interested in via our contact form.  Most custom orders will take several weeks to manufacture.

  • What are your adapters made of?

    All of our adapters are made with quality stainless steel, because it is durable, corrosion-resistant and is less apt to pick up potentially harmful abrasive material.

  • Can you make your adapters longer?

    We currently have chamber-length 2-3/4" adapters in the GaugeMate Gold, 4-1/4" adapters for Pocket Armory as well as mid-length adapters in the GaugeMate Platinum, which are 10" overall.  Currently we are not able to make anything longer than 10", but we can do other lengths as custom sizes.

  • Does my product have a warranty? What is your return/replacement policy?

    GaugeMate adapters are warrantied to the original owner to be free from defects in material and workmanship.  This warranty does not cover failures resulting from misuse, abuse, and alteration of the device or failure to comply with operation instructions.

    Products must be returned to GaugeMate in order to qualify for refunds or replacement.  We offer a lifetime warranty for replacements or repair.  Refunds are available within 30 days of product receipt.  All product returns are subject to a 20% restocking fee.

    Return Instructions:
    Please provide a complete description of the problem noted.  Include a complete address with a contact name, telephone number and e-mail.  All parts, packaging, and literature must be included for product returns. It is recommended that a tracking method be used for return shipments.

  • Do I need to send in my gun to be fitted for adapters?

    No, our adapters are all made to SAAMI specifications and are intended to be universal to any standard gun of the correct caliber.  If for any reason you have fit issues, please let us know and we'll be happy to modify or replace your adapters as necessary.

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