PETERSON BRASS 300 WIN MAG - LONG (50 PK)

Get more reloads on your .300 Win Mag casings with Peterson's .300 Win Mag – Long. If you are a handloader that wants more reloads from your .300 Win Mag casings, then you're going to love Peterson .300 Win Mag - Long casings. The regular .300 Win Mag casing Peterson makes is the traditional SAAMI spec’d version that headspaces off the belt. This longer casing version different is different however, as it headspaces off the shoulder. Traditional .300 Win Mag casings tend to show signs of case head separation after only 5 to 7 firings. This is because SAAMI specs for any calibre, list a minimum and a maximum tolerance for each dimension on the casing and the rifle’s chamber. With most calibers, the max dimension of the casing for length-to-shoulder (L-T-S) has the shoulder of the casing right up against the chamber wall. With a .300 Win Mag, unlike most other calibers, if your rifle’s chamber is cut to the SAAMI minimum for L-T-S, and your casing is at the max length-to-shoulder dimension, the casing shoulder is still .0095” away from the chamber wall. With the same minimum rifle chamber, a casing at nominal L-T-S is .012” away from the chamber wall. In a worst-case scenario, if the casing was produced at the SAAMI minimum L-T-S, and the chamber was cut at the maximum L-T-S dimension, the casing shoulder could be up to .026” away from the chamber wall. This is actually quite a a lot. That large gap is what causes the casing to stretch so much when it is fired. And it’s that st...

PETERSON BRASS 300 WIN MAG - LONG (50 PK)

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