View Full Version : Rimfire Ammunition Length

04-03-2015, 06:52 PM
How important is the length of rimfire ammunition?

When one loads for CF benchrest, the amount of jam or jump is quite critical for obtaining optimum accuracy, but in the case of rimfire ammunition, one does not have that option, so I made this little gauge to measure from the rim to the driving band - quite interesting results.

Quality ammunition (RWS, Eley) has the smallest variations, (+- up to 003in) but it has been possible to batch my ammunition (by length) and test fire some groups.

Apart from the fact that the longest cartridges give me the smallest groups, they also shoot to a slightly higher point of impact (5mm @ 50m) than the shortest of the batch.

This might explain the occasional flier when everything seems to be lined up and conditions have not changed.

My test rifle is an Anschutz 1411

* doghunter *