Preferred Brass
For a 6BR, there is one clear choice in brass--Lapua, with Norma the only real second choice. For the .308 Winchester, choice of brass is not so simple. Most of the .308 Win precision shooters we've interviewed do prefer Lapua brass, but others are very happy with Norma, Winchester, Hornady Match and even Remington. Black Hills uses Winchester-made brass for its match ammo, which is capable of .5 MOA or better in many rifles. The main advantage of Lapua brass is consistency and quality. Case-wall thickness is very uniform and most lots have shown less variation in weight than other headstamps. But Winchester brass performs very well in the .308. And, at $24/100, Winchester costs 40% less than Lapua brass. Even if you can potentially get more loadings out of a Lapua case, Winchester brass offers more bang for the buck. You'll find a lot of once-fired Federal Gold Medal Match brass available. While it tends to shoot accurately, we've found GMM brass is relatively soft compared to Lapua or Winchester, so the primer pockets tend to loosen up after just three or four reloadings.
In addition to commercial brass, many .308 Win shooters reload boxer-primed military cases such as Lake City, IMI, and Hirtenberger. The Lake City Match brass is pretty good. Some lots have been excellent. The standard Lake City fodder is inferior to Winchester. IMI brass has a reputation for being strong, but we advise you only to purchase it new. Some used lots of IMI brass from Israel have been defective. If you are looking for ultimate accuracy, IMI will probably disappoint you, though it's good for gas guns that are tough on cases.
The most important thing to remember about military brass is that the internal capacity will probably be less than commercial .308 Win brass, because military brass often has thicker webs or casewalls. Montana Marine reports his fire-formed milsurp cases hold 56 grains of H20 on average compared to 58 grains for fire-formed Winchester. Given the reduced capacity of military brass, you should reduce posted max loads by 1.5 grains when loading with Lake City or most other milsurp brass. However, the IMI MATCH brass is closer to commercial brass in internal case capacity (ICC). Kevin Beggs reports: "Fired, my IMI Match brass runs with an ICC of 55.0gr and bumping the shoulder back .001" will net me an ICC average of 54.0gr. LAPUA runs an average of 54.4gr and Federal runs an average of 54.3gr ICC."
