When Peterson Cartridge decided to come out with its own .338 Lapua Mag casing we perceived that there was not a source of really good, match-grade, sniper quality .338 Lapua that was made in the US. We decided that if we were going to produce .338s, we wanted ours to be as good as or better than the best foreign-made .338 L M.
So we spent more than a year studying the casings of the best foreign manufacturers. We ran scores of tests on annealing temperatures to get the grain structure just right. SAAMI, the standards organization for our industry, specs outside dimensions of casings but there are no specs on internal dimensions. So we cut casings in half and studied the internal geometry of the best, to uncover their secrets, and where possible, improve on them. In our lab we have an electronic machine that measures the force required to insert a projectile into the case mouth – what we call neck tension. This enabled us to ensure that our casings were optimal for bullet release. The end result is what we believe to be the most accurate shooting .338 Lapua Mag casings on the market.
We’re not the only ones to think these are exceptionally good casings. We sell a ton of our .338 LMs to international sniper units. And we know of at least one hostage situation in the US that was resolved with a round using Peterson .338 LM brass. So if you would like to use the case used by military sniper units and police SWAT teams, you need look no further than Peterson Cartridge.
Pittsburgh, PA (April 28, 2018) – Peterson Cartridge Co. of Pittsburgh, PA today announced the addition of .338 Norma Magnum to its growing family of rifle casing calibers.
When Peterson Cartridge set out to produce .300 Norma Magnum casings (which it recently introduced) it also added .338 Norma Magnum to the Tooling Development schedule. The .338s are now available, and initial test results are excellent.
According to Derek Peterson, president of Peterson Cartridge, “Our development goal for both of the Norma Magnum calibers was to produce casings that outperform the competitor’s product … and we did it. We make our Norma Magnums with a harder head. Our casings tolerate higher pressure. And you’ll get more reloads from Peterson casings.”
When Peterson produces a casing in a new caliber for the first time, it performs an extensive list of Quality Assurance tests and trials before making it available for sale. One of those trials involves the following:
- Load 5 cases at certain percent above Max pressure, and fire each five times.
- Take 3 of those casings, increase the pressure, and fire each, five more times.
- Take one of those casings, increase the pressure again, and fire that casing 10 more times.
After running this protocol on the new .338 Norma Magnums Peterson’s ballistician reported the following:
- Standard Deviation on muzzle velocity was single digit.
- There was no detectable heavy-bolt-lift, sticking in the rifle, primer gas leaks, blown primers, cracked necks or bodies, or case-head-separation signs throughout testing.
- Primer pocket removal force showed only very minor reduction due to pockets opening up.
- After firing the last case 20 times, at above recommended powder levels, the case appeared the same as it did after the third firing.
The ballistician concluded, “These cases were found to be strong, durable, well-made cases that should satisfy the most discriminating shooter.”