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Mouth Chamfering

Chamfering

After thousands of rounds of function testing, and years of degradation testing, we have finally eliminated the step of chamfering the inside and outside of our casing mouths. If you are familiar with the “Technical Articles” section of our website, you might remember the article we did titled Peterson Has New Coating. In that article, we introduced our customers to the new coating we developed for use with our casings. That article is located here: https://www.petersoncartridge.com/technical-articles/posts/2018/november/peterson-has-new-coating/

We will briefly summarize the article on the new coating. The goal of the testing we did, was to reduce the scraping and gouging a bullet experiences when it is inserted into a new casing. After a few months of pretty exhaustive testing, we found that chamfering the inside, and outside, of our casings didn’t prevent bullet damage. The actual cause of the bullet damage was due to the surface finish on the inside of the casing mouth. This is why coating our casings in our lubricant/anti-tarnish prevents bullet damage more effectively than chamfering ever could.

During our manufacturing process, we clean each casing nine (9) different times before it is packaged into boxes. This thorough cleaning is part of what gives our casings their jewelry-like finish and shine. However, as it turns out, really clean brass does not allow copper to slide over it smoothly. As you are already likely aware, copper is what almost all bullets are jacketed in or completely constructed of. This tackiness of the copper, sliding along the inside of the casing neck, was actually causing the bullet jackets to gall to the inside of the casing neck. This galling is what was actually damaging the bullet jackets when they were inserted into the casings, not a burr on the inside of the mouth, like we originally thought.

As the result of our testing finally being complete, as of March 31, 2020, we will no longer be chamfering the inside or outside of our casing mouths. Do to our accuracy testing, we are confident our customers will not notice any difference in our casing performance. If you have any further questions about this change, please feel free to contact our customer service manager, Ben Preston, at bpreston@petersoncartridge.com or 724-940-7552 (Ext 205).

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Extremely consistent, American-made brass rifle casings and ammunition, designed for long-distance shooters.