I do NOT recall the details, but IIRC, there were certain models of Ross rifles that, if the bolt was assembled incorrectly, THE BOLT COULD FLY BACK INTO THE SHOOTER'S FACE! Perhaps those familiar with the Ross can supply details.
That was the case with the 1910 (Mark III) Ross (which was the final version, and standard issue going into WWI) but this potential hazard has been blown out of all proportion, since cases of it actually happening are virtually unheard of. It should be noted that if this unlikely condition exists, the bolt does not fly right out of the rifle, but stops at the rearmost position of travel.
In "The Ross Rifle, Monograph" produced after WWI for the Canadian government, its author Col A.F. Duguid noted that there was only one authenticated instance of a fatal injury to a firer of a Ross rifle. He also noted that during training of Canadian troops at Camp Valcartier, a total of 22,128 Ross Mk III rifles fired a total of 4,589,040 rounds with only one minor casualty recorded, that being from a blow-back.
To put things into perspective: first off, it is rather difficult to actually reassemble the bolt incorrectly and still manage to get it back into the rifle, since it doesn't want to go back into its channel in that condiition, and you really have to work at it to get it in!
Also, if you are the least bit knowledgeable, the fact that a bolt is assembled incorrectly is readily apparent at a glance: the locking lugs should be well ahead of the bolt body (about an inch, or "thumb width"). This ensures that the locking lugs of the bolt are far enough forward to engage the mating lugs inside the rear of the barrel, when the bolt turns partway around as it is pushed forward. If the bolt lugs are back against the bolt body, the bolt is assembled incorrectly, so that when it is pushed fully forward the lugs do go out of sight but don't engage the inner lugs ... (You may observe that this "interrupted thread" locking system is the same as is used on artillery pieces ... and is a very strong system)
Finally, Canadian military regulations in any event strictly prohibited the disassembly of a rifle bolt by anyone other than a certified armourer, so you'd have to be in breach of that rule to put yourself in any danger.
All of that being said, simply because this unlikely possibility existed, a modification was introduced, in which a beefy "pin" was set into the outer bolt body, projecting inside, to prevent reassembly of the bolt incorrectly. Thus, almost all surviving Mk III Ross rifles have been "pinned" to render incorrect bolt reassembly impossible. Interestingly, the bolt of one of my own Mk III Ross rifles remains in it its original "unpinned" state ... making it a relative rarity:
The
real problem with the Ross rifle, as a sporting rifle design modified for military use, was its exceptionally fine tolerances. It worked very well (and with exceptional accuracy) when clean and fired with correctly dimensioned cartridges. However, under trench warfare conditions, and with hastily mass-produced cartridges which were prone to being "out of spec", it was prone to jamming ... if not locking up almost irreversibly. The Ross has been referred to as
"The finest target and sporting rifle to fail miserably as a battle rifle."