12 Gauge Shotgun SAMMI bore diameter. .729. Note: Most modern guns are over-bored to .732 to improve patterns and lessen recoil, etc.

Choke Constrictions in thousandths of an inch smaller than the SAAMI bore of .729

After extra full sizes are no longer listed in smaller than your bore, they are listed as the measurement of the bore.

• Cylinder= .000
• Skeet= .005
• Improved Cylinder=.010
• Light Modified=.015
• Modified=.020
• Improved Modified=.025
• Light Full=.030
• Full =.035      = .694 Turkey Choke
• Extra Full=.040      = .689 Turkey Choke
  • .059 = .670
  • .064 = .665
  • .069 = .660
  • .074 = .655
• Tightest .079 = .650