[MA45XP]

G'day gentlemen.
If I may, here's a couple of points I'd like to chuck up for your consideration. It's a well known fact that a lot of .303British ammo hasn't got the best reputation for going off at the same time as you pull the trigger. Most will know it it as POF or Pakistan Ordnance Factory mkVII. The POF ammo burns a little dirtier than most and can be a little inconsistent with regard to muzzle velocity too. Throw up the fact it had been stored in poorly sealed packaging for a long period and thats where your biggest problem begins. I'm not sure off hand if it was ever decided whether the cause was deterioration of the primer compound or the powder, maybe both... but the result is hangfires or even failure to fire. If subjected to the same conditions, any ammo would be effected in a similar way, so unless you can be sure their ammo was with your ammo for the last 50 years, there is no real way of being sure it will be the same to fire anyway. All you can do is try it... and if it just goes click, make sure you hold the rifle pointing safely downrange for at least half a minute before you even think about opening the bolt. Yes, over 30 seconds... I have seen hangfires that took near that long to go off. If it goes off as you open the bolt... well, thats when people get hurt, so take every precaution when using ammo that might be a little suspect.

A well spread misconception is that cordite somehow wears out rifles. The truth is it is only very marginally hotter than the more modern powders that replaced it. The chamber isn't worn, but the leade is, the leade into the rifling, the first point the expanding gasses contact outside the case neck. It isn't the heat from the individual round, but the rate of fire. The heat concentrates itself onto edges, it flows quickly across smooth surfaces but when it hits an edge, it changes direction and the effect transmits heat into the edge. When this heat builds up over subsequent rounds without the chance to cool between, the surface at the edge reaches critical temperature (melting point) and the continuing firing causes the metal to be removed much like an oxy torch cutting. This is called throat erosion. As these pits appear, they create more edges for more heat to build on for more erosion to occur. One other problem with this ammo is the compound the primers are made of. The mineral salts in them travel down the barrel with the hot gasses and settle into the pores of the bore while they are hot and open. As they cool the salts are trapped in the surface and cannot be scrubbed out. To remove them, you have to pour boiling water down the bore and then clean conventionally. If not removed, they cause rusting very quickly, leaving pits which in turn have edges, which if raised above critical temperature, will be starting points for erosion.

In a bolt action rifle, erosion will take many many hundreds, maybe thousands of rounds to be really evident. These barrels were lifed at between 6 and ten thousand rounds in battle conditions, firing cordite ammo.

Cordite ammo is fine to use as long as you take the right precautions if you have a hangfire/ fail to fire.
Don't fire full magazines repeatedly rapidfire, which can heat the leade of your barrel above critical temp.
And lastly, make sure you clean the mineral salts out of the bore with boiling water after any corrosive primed ammo is fired.