From Hornady:
To use the L-N-L O.A.L. Gauge, you will need to purchase a Modified Case to fit your firearm’s chamber and thread it onto the Gauge.
For all bolt action and single-shot firearms, or any firearm with straight-line access to the chamber. This model is preferred, as it is most precise and user friendly.
Please contact Hornady directly with any concern about performance, manufacturing defects, or warranty issues. Their contact information is found on their web site www.hornady.com. Their main switchboard phone number is 308-382-1390 Monday thru Friday 8am to 430pm Central Time.
