I keep a small supply of DA for zombie attacks, errant dinosaurs, the End of the World owing to the Long Count returning to 0.0.0.0, a takeover by the International Bankers or the Commies or some such, but I do it for one reason: you can't reload the damn stuff! Until at least 1952 (60 years ago), Dominion Arsenals ammo was made with that lousy corrosive-and-mercuric Berdan primer which wrecks your rifle and your brass at the same time. They changed over to NCNM Boxer caps just shortly before they stopped making .303..... and that's no fun at all.
OTOH, the NICEST .303 brass ever made for reloading purposes was the DI: Defence Industries. This was made only from 1941 through 1945, but they made lots of it, so there still are small bits of it around. Noncorrosive, nonmercuric, Boxer, really good brass and the rims are ALL right at .063" and so the stuff headspaces correctly if your rifle is in good nick. I neck-size only when I can get away with it, have a couple boxes here which are on their 15th firing in a Ross and still don't want to be trimmed.
Secrets of brass life: start with the best brass you can get, fireform and neck-size, load DOWN about 10% from Service specs, watch the case-length (especially in LEs) and anneal lightly after half a dozen firings, then every dozen after that. Do it right and the stuff will last MUCH longer than you might believe.
Secrets of bore life: keep pressures and temperatures as low as possible, CLEAN ammo and don't over-clean your rifle.
Happily, these can be COMBINED for practise purposes by using the C.E. Harris UNIVERSAL load for military rounds: 13 grains of Red Dot with a 180 CAST bullet. BUFFDOG turned me onto this one; it is his 200-yard gopher load. It gets about 1800 ft/sec with a 180 cast out of a .303, recoil is minimal and bore life is halfway to forever. For a super-accurate .303 load, try 37 grains of 4895 with a Sierra 180 Pro-Hunter flatbase, seated to the OAL of a Ball round; comes out about 2250 ft/sec from the SMLE, 100 ft/sec or so faster from a 1910 Ross. If your rifle is shooting well, this load can touch bullets at 100, sometimes even overlap them. You need a LOT of sandbags, though! Calculate for drop using the ACTUAL MV and "if you can see it, you can hit it" although you have to know the range.
Of the current makers, Prvi Partizan seems to be making the brass closest to the old military spec, although NOBODY has twigged to the fact that the rim bevel was there for a PURPOSE.
Have fun!
That's what it's all about.
Hope this helps.
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