The rifle data contains data for most of the popular cartridges. The components specified were those that were commercially available to the handloader at the time the tests were performed.

The powder charge weights specified represent loads that developed Maximum Allowable Chamber Pressures with the test barrels used and components specified, with the exception of loads that are specified as (C) compressed charges which may represent case capacity rather than maximum chamber pressure. All tests were conducted utilizing commercial barrels in a Universal Receiver.

It is not unusual for reloads assembled with particular components and fired in the individual reloader's gun to give ballistic results (particularly chamber pressures) that vary in either direction from the published data. To compensate for any component and/or gun combination that would tend to yield pressures in excess of the published data, it is recommended that the powder charge be reduced 10% initially. (This reduction in powder charge weight should also be made each time that any of the components in the load are changed.) After firing several loads at the lower powder charge weight - without ANY evidence of excessive chamber pressure - the powder charge weight may then be increased in 0.5 grain increments as accuracy needs and pressure indications permit. The subject of excessive pressure along with illustrations is included in most reloading manuals, and should be read before attempting any reloading.

Always make certain that you use the correct ammunition in your rifle.

This data must be used only with IMR Smokeless Powders. Never use this data for powders that may have similar numerical designations!