Retief Kruger of Inyathi demonstrating the Hornady OAL Gauge
Illustration of "jump" parameters
Once the fundamentals of reloading rifle ammunition have been mastered, many reloaders start to realize the potential of increased accuracy with custom ammunition tailored to a specific rifle’s requirements.
Those reloaders who want to up their game would do well to take note of the importance of precise bullet seating depth. Regulating seating depth of the bullet and the resulting "jump" to the rifling is widely regarded as a fundamental element in obtaining improved accuracy. A few thousandths of an inch change between the bullet and the rifling can make the difference between mediocre accuracy and true tack-driver results.
A bullet’s jump to the rifling lands in the barrel is a very important calculation for accuracy. Too short and the bullet can angle which can cause inaccuracy. Too long and the bullet can contact the lands before being fired which can increase pressure within the cartridge case which is not only dangerous, but leads to inaccuracy and wears cases out faster.
Hornady’s Lock-N-Load O.A.L Gauge provides an easy solution in measuring a rifle’s chamber length. The O.A.L. stands for Overall Length, and this tool gives measurements of the rifle’s chamber with accuracy down to .001". It is recognized as an incredibly accurate, easy-to-use and reliable method of obtaining that critical information for correct bullet depth seating.
The Hornady system consists of the O.A.L. Gauge, a red aluminum tube with a plastic internal pusher rod, and a “Modified Case” (sold separately), that has been bored and threaded at the base (where the primer pocket usually is) for attachment to the pusher rod. These specially prepared modified cases have a .002" oversized neck to accept the same bullets the reloader intends to load. The bullet is then pushed through the case by the pusher rod to the front of the chamber. Overall length measurement of the chamber can now be accurately taken.
Are there other ways of achieving the same result? Indeed there are. If the reloader is looking for accuracy he can make different loads in different lengths, and eventually arrive at the same place. But how many rounds did the reloader have to go through for each load before the ultimate load was found? Ten rounds or a hundred? And this needs to be done for every bullet weight and profile, for each of the rifles for which there will be reloaded. With bullets costing anywhere between R5 and R20, getting the measurements for correct seating right early on will save a considerable amount of money, effort and time.
The Hornady Lock-N-Load O.A.L Gauge is available from Sons Of Guns in Parys and Jan Lubbe can be contacted on 082 421 1122.
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