The Shooters Box case and ammunition gauges are manufactured right here in Malden Massachusetts, by American workers on American machines!
Made from T6 6061 Aircraft Grade Aluminum, beautifully anodized in red color and built to last a lifetime. Each gauge is manufactured to S.A.A.M.I (Sporting Arms and Ammunition Manufacturers Institute) chamber specifications. The gauge will measure the maximum cartridge length (full overall length), and the minimum and maximum case length. The lower step indicates the minimum allowed case length and the upper step (face of the gauge) indicates the maximum allowed case length.
A loaded cartridge should fit freely and easily into the gauge. A cartridge that does fit properly may not correspond to the proper chamber dimensions.
Place a clean cartridge into the gauge and make sure that it is completely seated by itself with no assistance to seat it. The head of the bras should sit flush within the lower and upper step of the gauge. If the cartridge sits higher than the upper step then your brass might be too long. It's easy to check by eye or with the help of a straight edge or steel rule. With the cartridge in the gauge check the backside to make sure the tip (bullet end) is not protruding outside the back face of the gauge. If the tip of the bullet protrudes from the end of the gauge it is longer than the maximum allowed cartridge length. It is If the cartridge does not easily drop into the gauge without assistance there is most likely something wrong with the dimensions of your cartridge. A cartridge that will not easily fit into the gauge may or may not fit the chamber of your barrel.
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