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Peterson Brass .300 Winchester Magnum - Long Unprimed 50/Box

SKU PET-U4PH7093L
£96.67

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Peterson Match-Grade Brass rifle casings are manufactured on new, state-of-the-art production lines which use cutting-edge technology to produce some of the most precise and consistent casings on the market. Peterson are committed to producing Match-Grade Brass that enables their customers to get more reloads per casing than industry average.

Shooters that reload .300 Win Mag casings have often wished they could get more reloads from their casings. Well now you can!

Derek Peterson, president of Peterson Cartridge explains, “Traditional .300 Win Mag casings tend to show signs of case head separation after only 5 to 7 firings.

“Here’s why. The 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 calibres, 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 .300 Win Mag, unlike most other calibres, 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. That might not sound like a lot, but it is.

“That large gap is what causes the casing to stretch so much when it is fired. It’s that stretching that causes premature case head separation.”

Peterson continued, “With Peterson .300 Win Mag- Long casings, we make them with a longer L-T-S dimension. All the other dimensions are SAAMI spec. But the longer L-T-S prevents the casing from stretching excessively on the 1st firing. The casing has more support, which translates to less stretching, which translates to longer case life.”

The entire brass drawing process takes place in their manufacturing facility located in Cranberry Township, PA.