Gun Barrel Diameter Gages:
The gun barrel gauge is a two-point comparator gauge, which needs regular re- calibration. It is a measuring instrument, which can be used in the manufacturing process or to check the wear during the use of the rifle or pistol. Depending on the production proc- ess, not all gun barrels are 100% identical. Also, when guns or pistols are fired, changes take place inside the barrel, which affect their accuracy. With the gun barrel gauge, these changes, known as muzzle expansion or erosion of the groove or land zones, can be accurately determined with a repeatability 0,005 mm throughout the entire length of a barrel, provided that the surface roughness of the barrel to be checked is max. 0,005 mm. For each calibre from .22 to .45, a different measuring sleeve and guiding nose can be selected, in relation to the corresponding land , rifling and number of grooves.
When ordering, we always need a sample of the barrel for our tests.
The instrument ready for use is designed as follows:
- A guiding nose guides the measuring instrument in the groove of the rifle- Nose guided Measuring sleeve land or groove (272-080 Land or 272-081 Groove)
- Extension Ø 5 mm for caliber from 5,5 6to 7,62; Extension Ø 8 mm for caliber 9 – 14,5
- Holder allows 3600 rotation of holder extension. Indication stays in easy to read position for operator while measuring sleeve and holder extension rotate 3600 down gun barrel.
- setting ring (272-090 Land or 272-091 Groove.) Specify size and tolerance
- Optional plastic bushing holds setting ring in extension shaft for ease of use.
- Holder with dial gauge , extension , measuring sleeve
- Measuring Sleeve, Guided Nose and Fixing screw