GA Store

The Official GAP Merchandise

Apparel, Outdoors, Survival and more

  1. Home
  2. 6mm GT Headspace Gauge (PTG)

6mm GT Headspace Gauge (PTG)

Out of Stock

This Headspace gauge is manufactured by Pacific Tool and Gauge

The 6mm GT is a new cartridge design from George Gardner (owner, GA Precision) and Tom Jacobs (owner, Vapor Trail Valley Bullets) that optimizes cartridge dimensions for low SD's and extremely consistent performance both on the bench and in practical precision application (PRS style competitions). 

  • 35 degree shoulder for trouble-free feeding, specifically with detachable magazine systems. 
  • No magazine inserts or modifications required; just use standard out-of-box 308 Win. AICS or AW magazines. 
  • Optimal case efficiency nearing 100% volume usage @ 33-35 grains of Varget. 
  • 3020-3100 fps with 103-105 grain bullets or approximately 3000 fps with 115's.


  • Dies are available through GAP: by Redding, Hornady and RCBS. 
  • Brass is being produced by Alpha Munitions and Hornady
  • typical powder to be used: Hodgedon Varget or H4895