The Shooters Box Patented Cartridge Gauge For 308 Winchester

Now with Patented Overall Length Indicator Cut !

With our brand new advanced Patented Tri Step and Overall Length Indicator design you will get the best most advanced cartridge measuring gauge made today!

The new design incorporates a cut in the base of the gauge that measures the minimum and maximum overall acceptable length for your cartridge.  

Until now there was no easy way to measure the minimum acceptable overall length of your loaded ammunition.  Now with this  revolutionary design it's so easy it takes less than a second! Simply drop a loaded cartridge into the gauge and make sure the bullet tip doesn't extend past the gauge base or be less than the bottom of the groove cut in the base of the gauge

(see pictures for diagram explanation).

No longer is it necessary to measure each cartridge with your calipers, taking time and aggravation. This gauge DOES IT ALL!  These new patented gauges measure all important aspects of your ammunition.

• Chamber Headspace

• Maximum Case Length

• Minimum Case Length

• Cartridge Diameter

• Maximum Overall Cartridge Length

• Minimum Overall Cartridge Length (NEW FEATURE!)

No need for multiple gauges or to measure each cartridge  with calipers, this is an all in one gauge!

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) minimum chamber / headspace specifications.  The gauge will measure the maximum cartridge length (full overall length), the minimum and maximum case length, the maximum case diameter and the maximum headspace.

The difference between the top step (face) of the gauge and the middle step shows the maximum allowed chamber headspace.

The middle step shows the maximum allowed case length.  A loaded cartridge that is inserted into the gauge should not be higher than the middle step.

The bottom step shows the minimum allowed case length.  A loaded cartridge that is inserted into the gauge should not be lower than the bottom step.

The bottom of the gauge indicates the maximum overall acceptable overall cartridge length and the ‘groove’ in the bottom of the gauge shows the minimum acceptable overall cartridge length.  See the picture for more information.

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 seats by itself with no assistance to seat it.  The head of the brass should sit flush or between the middle and lower steps of the gauge.  If the cartridge sits higher than the middle step then your brass might be too long, if it sits lower than the bottom step it might be too short.  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 overall cartridge length.  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.  Keep in mind that most rimless rifle cartridges stop on the 'shoulder' of the case, the cartridge does not stop (sit) on the mouth of the brass when in the chamber of the barrel.

Complete satisfaction guaranteed!

USA Patent No. D846,276 and D999,073 - European Patent No. 005505526-0001 - UK Patent No. 6039401

PLEASE READ THIS!!!! THIS GAUGE IS NOT NOT NOT A SHOTGUN ADAPTER!!!  THIS IS A CARTRIDGE GAUGE THAT IS DESIGNED TO MEASURE AMMUNITION FOR PROPER SIZING.  IF YOU ARE PURCHASING THIS THINKING IT IS A SHOTGUN ADAPTER IT IS NOT!!!!  We currently do not manufacture a shotgun adapter for 308 Winchester caliber ammunition.  Our shotgun adapters can be found on our other listings.

WARNING!!!  NEVER ATTEMPT TO RESIZE LOADED CARTRIDGES.  THIS IS EXTREMELY DANGEROUS AND COULD LEAD TO AN ACCIDENTAL DISCHARGE CAUSING INJURY OR DEATH.

In some instances your cartridge may sit flush with the lower step BUT the brass may be shorter than the SAAMI minimum specifications.  In this instance your ammunition may still fire and function correctly but it is up to you to confirm this will not cause an unsafe condition.  It is the reloader's responsibility to determine the cause of incorrectly sized cartridges and to correct it.  In some cases ammunition previously fired with maximum powder loads or with abnormally large barrel chamber diameters may not fit this gauge.  This is due to some resizing dies not being able to fully resize the brass cartridge all the way down to its head. Any ammunition shown in pictures is purely for representation purposes and is not included with the purchase of this gauge.