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Haven't gotten around to it yet. I'd like to find the earlier article first, it gave a much more detailed account of just how the erosion caused the bullet to become stuck in the bore.
I found it very difficult to convince people that erosion can cause unsafe bore conditions. Most seem to believe that a loose bullet to bore fit only results in lowered pressures and poor accuracy.
Much has been made of the recorded instances of jacket failure involving the tublar jacket bullets and Dum Dum bullets where the nose of a FMJ is filed away. So much so that every stuck jacket is automatically assumed to have involved such a bullet.
Townsend Whelen wrote of having fired more than ten thousand rounds of milspec FMJ .30-06 with the bullet noses filed off to make Dum Dums without a single shed jacket. Though I don't doubt his claim, its still not a good idea to fire mutilated bullets, and there has been an incident of a shooter being partially blinded when using a more recently manufactured tublar jacket bullet.
Shedding of jackets, also called "blow through" can happen even with FMJ bullets in good condition, as the records of the US Chief of Ordnance speak of in relation to the early problems with .30/03 and .30/06 when double base powders containing 30% Nitroglycerin were in use.
At nitro percentages that high the erosion takes on a different character to the more common gradual erosion of single base powered loads.
Hiram Maxim, in testing of MG barrels to destruction, recorded the appearance of an "egg shaped" void just in front of the throat of the bore. This sort of void ahead of the chamberallows gas blowby that can heat the jacket and soften the core causing separation. The superheated jacket material can then become fused to roughened surfaces of the bore, the sides of the jacket come to a halt but the core keeps moving, blasting through the nose of the jacket.
For some reason many Lee Enfield owners don't seem to realize or recognize that the action is not immune to catastrophic failure if measures are not taken to insure that they use only good quality ammunition that does not exceed recommended pressure limitations.
Too many also don't seem to recognize that bore condition is extremely important to safety.
Most milsurp owners will never fire as many rounds through their rifles in twenty years as an infantryman may have fired through that same rifle in a weeks time. Odds are that any particular owner will never have a problem, but trusting to odds rather than taking simple precautions is not the best way to go.
In recent years I've seen hundreds of rifles show up at estate sales and auctions , rifles which may or may not have been subjected to an unknown number of rounds of milsurp ammunition of unknown quality and then set aside for decades.
rifles such as these may have never been properly inspected before being sold off, between wars surplus rifles were often sold at scrap metal prices by the pound going for ten to thirty cents a pound, and certainly not inspected or serviced since then other than a cursory and possibly inadequate cleaning.
I've examined rifles that looked very nice on the outside, but had bores with broken away chunks of land, large voids mid bore where a steel rod had beaten down the lands as the rod twanged against the breechface when pushed in from the muzzle, Muzzles worn to an oval by pull throughs, Chambers out of the round due to pull through "cord wear", and even marks in the chamber that revealed that the chamber had once been plugged and the plug later removed.
A friend bought a Drill Purpose No.4 to strip for parts and when he dropped a rod down the bore to see how far its welded in chamber plug extended the plug simply popped out.
Other than a ring in the chamber from the plug having been driven in before welding only a very tiny burn line on the rear of the receiver ring remained to show it had once been demilled.
I don't doubt that many DP'ed rifles have been reactivated and sold to unsuspecting buyers. Some may have suffered little damage while others may be accidents waiting to happen.
The uncertain origin, and history of storage, of much milsurp ammo is another factor.
Some .303 ammo has remained usable after decades of storage in temperature controlled facilities, that ammo is unlikely to cause problems. Other .303 ammo that has shown up from time to time has proven to have been dangerously poor quality from the day it was made, or in some cases remanufactured.
Even well made ammo can become dangerous if not stored properly.
I ran across a quote from one of the Ammo pocket books that stated that nitroglycerin that sweated out of cordite could soak into the over charge card wad. The soaked card then became an explosive seperate from the charge itself.
Tests on ammunition cases on the Indian Northwestern frontier revealed that after a few hors of direct sunlight temperatures inside the case reached 160 degrees F, Nitro begins to sweat out of cordite at 125 degrees F. If it doesn't soak into the wad it forms a pool inside the cartridge case.
Hangfires usually ignite within 20 seconds or so, but a dented primer can ignite when ejected. Ground glass was added to most WW2 era primer mixtures to give a source of friction, when the already dented cap with dislodged priming mixture receives a jolt it can detonate. If this happens with the bolt unlocked injury is pretty much certain.
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