The AN1 is designed for the Anschutz model 54 single shot action, the optimal barreled actions for use with this kit are the 18xx and 19xx series, the AN1 kit has a unique barrel mounting system, an aluminum sleeve is epoxied to the barrel just ahead of the action, this sleeve fits into a precisely bored hole in the stock, this leaves the action free floating, this "zero stress" mounting system helps to promote the highest possible accuracy.

The photo below shows how the action sets much closer to your face (about 1.5") with the stock adjusted to the same buttplate/cheeckpiece relationship as the standard Anschutz stock, making loading from the shoulder much easier