BIG problem, guys, is that the basic LEE action is SPRINGY. It's not WEAK, as the Yanks say, but it IS SPRINGY. And Service-level ammo was up at the sharp end of what could safely be run through a rifle in pretty decent condition, ONCE, and THEN thrown away.
The Brits didn't police up their pretty battlefields and collect up all the brass for reloading; that was left for the Swiss and the Swedes. The Brits just went on to the next battle.
When the rifle fires, the Bolt COMPRESSES and the Body (action, receiver) STRETCHES. This can (and does) produce a sort of a headspace condition every time you pull the trigger, even in a perfect rifle.
Easiest way around this situation is just to load DOWN a bit. Even 10% downloading on the MV will give you up to a 20% drop in peak pressures, and this means LESS Body stretch, LESS bolt compression (just about eliminating both, as a matter of fact). I am gettng EXCELLENT results, accuracy-wise, by dropping the MV for a 180 down to 2250 ft/sec (the actual 1910-proven-most-accurate velocity with the 174) and by staying with a relatively-quick powder (I'm using 4895 and 4064, sometimes as quick as RL-7).
Anyone getting second-reloading separations from the .303 or from any other cartridge, is loading too hot, or has something wrong with the rfle, or both.
BIGGEST SINGLE KILLER of .303 brass is LENGTH. Keep your brass trimmed and watch the failure rate disappear. 2.222" was okay for Service ammo; you knew the chamber was deep enough. But try to keep your brass back about 10 thou from that, keep your pressures down, centralise your brass on initial firing, seat to the OAL of a Mark VII Ball round, neck-size only, then sit back and watch your scores go up..... and your brass life with them.
Hope this helps.
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