Thread: Hornady OAL Gauge

Hornady OAL gauges are OK but only if you use a case fired in your own rifle as the testing case. Easier said than done but I have a mate with the correct tap to tap out the primer pockets once drilled so therefore the cases I use for measurement have all been fired in each of my rifle chambers - one case for each rifle. If you don't use your own cases I have seen errors up to 5 thou using the Hornady cases. You can check by measuring to the datum point of the shoulder of you own fired case (Hornady have gauges for this) and then the Hornady case and doing the maths from there, and then use the Hornady case with the difference factored in. Also when doing the projectile pushed up to the land stage do the measurement several times and average the result. You should however be within a few thou of each measurement. If not the things that will give you very differing measurements are worn/fire cracked lands or a carbon ring (carefully clean the throat area with JB or autosol and redo the measurements). Hornady OAL gauge is OK but obviously only a starting point for seating depth and a check to make sure you aren't into the lands and having the risk of a high pressure spike. Looks like you had taken that into account at any rate.