Peterson product close to perfection

Top brass!

Peterson product close to perfection says Daniel O’Dea

One of the primary factors in achieving firearm accuracy is the elimination of variables which covers a whole gamut of areas be they action bedding, scope mounting, propellant or projectile selection to name but a few. The least change there is between shots, no matter how small, the better as consistency breeds accuracy not just with the shooter but with hardware and components too.

For those chasing the ultimate accuracy, match-quality brass is all but essential. You can have a great rifle and optics and even excellent projectiles, primers and propellant but that can all be undermined if there’s no consistency in your brass. Where do I start? If primer flash holes are not uniform, ignition may be different between shots and if case length differs, neck tension might vary while inconsistent case volume can create more variance. Lack of case concentricity may present the projectile differently each time a round is chambered and so on. Any one of these things can make a small difference but start stacking up multiples of them and it can make a tangible variance on paper.

Of course you can go overboard. I know there are plenty of reloaders saying: “Hang on, I use any old mixed brass and still shoot MOA or better!” It may not matter if you’re just after basic field accuracy and if it’s good enough to hit a small dinner plate at 100m, you won’t miss much in the field. Yet regardless of whether you’re shooting a benchrest match, hunting or just plain vermin control, it always pays to give yourself the best chance of success from the get-go so why not start with good quality brass?

Currently there’s a decent choice of worthy brass on the market but the Peterson brand of match-grade has to be right up there among the best. As a US company based in Pittsburgh, Peterson make their brass on a new state-of-the art case line and I’ve drawn much of the following information with the help of their website but the  process basically goes as follows.

Cases start life as a part of massive coils of C260-grade cartridge brass which are split into narrow coils before being fed into a cupping press where brass cups are punched and formed. The finished cups are stout and wide before being processed through three separate drawing stages to elongate them to the desired length with excess brass trimmed, at which point they look like a brass tube with a closed end.

In the next step both the primer pocket and headstamp are formed where the case is rammed against a pocketing tool to create the primer pocket, followed by a bunter which flattens the bottom of the case and adds the headstamp. Then the extractor groove is cut. In a course similar to a horizontal lathe, the case is clamped on a spindle and spun at high speed while a profile cutter is introduced to cut the groove.

Now resembling a straight-walled case, tapering commences with cases tapered through three separate presses to be refined into their final body, neck and mouth dimensions but are still without flash holes. They also need to be trimmed to final length and in this process, specially designed carbide cutters which are frequently changed out are used to prevent any burring inside or outside the case mouth, then the flash hole is punched.

Inherent to case performance, extra-special attention is given to ensure all flash holes are uniform and free from burrs or tearing. Then both case mouths and necks are annealed and as with the flash holes, this step is inherent to performance as uniformity in neck tension (or how the case neck grabs or holds the projectile) is also an important step in ensuring premium accuracy. To this end the annealing job is via an induction method rather than flame annealing, as induction produces a more precise control of temperature for each individual case. Lastly the cases are chemically washed which removes any leftover lubricants accumulated in the manufacturing procedure while a combination of acids, detergents and anti-tarnish compounds give a finished product with a beautifully polished lustre.

Local distributor of Peterson brass, SJS Trading, provided a box in 6.5 Creedmoor for review purposes and on first inspection all the effort that goes into manufacturing was clearly evident. Brass was bright and neatly presented with not a burr or blemish to be found, primer pockets and flash holes appeared perfectly concentric as did the case necks.

The finished match cases come packed in case guard-type ammo boxes of 50 which prevents damage in transit and after inspection I’d no qualms about jumping straight to loading without going anywhere near a sizing die. Not only that, the boxes themselves are of premium manufacture with moulded plastic pivot-type hinges as opposed to just a hinged seam. It’s not uncommon to pay anywhere from $15-$30 for these ammo boxes alone which should last for years and save you buying them separately.

I didn’t go overly scientific in testing these cases though I did individually weigh and measure them as this can give a good indication of consistency and volume. If they weigh the same they must have the exact amount of brass in each case, therefore it follows case thickness and volume should be consistent, likewise case length for neck tension and so on. Over 50 cases the average weight was 163.37gr with a standard deviation of 0.385 of a grain. Case length average was 48.57mm which is pretty much the recommended trim length with a standard deviation of a minuscule 0.027 of one millimetre.

Satisfied with those results all that was left was to prime the cases, load them with a sufficient amount of ADI AR2209, top them off with Hornady 140gr ELD Match projectiles and head for the range. For testing I was using my 6.5 Creedmoor Howa 1500 which is currently sitting in a KRG Bravo chassis from another review. Accuracy has always been excellent out of this Howa with ½ MOA or even better being pretty standard at regular intervals and my loads with Peterson brass continued that trend.

My 6.5 Creedmoor loads are moderate and the brass came out nicely fire-formed and bright and I’ve no doubt in such applications case life should be quite lengthy. If any indication is needed the reloading data sheet provided as standard with the ammo box has provision for marking ‘times loaded’ x 20. Of course quality comes at a price and Peterson brass is not cheap but based on its growing reputation it might just represent excellent value. Perhaps now more than ever is a time where you’re better investing in a quality product guaranteed to perform and be long-lasting. For more and calibre availability visit SJS Trading Co

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