Wax is not oil. If the makers of the round, whether it's externally lubed.22 LR bullets or GP11 with its special ring around the base of the bullet, have placed wax around the cartridge, then it belongs there. That's a far cry from me rubbing CLP or motor oil onto otherwise dry 7.62 NATO cases.
Incidentally I have applied motor oil on cases and I have left RCBS water soluble on them too.
Those oilers on Nambu's, schwarzlose, breda light machine guns, it is very unlikely that that anything but straight mineral oil was used in the tanks.
These oiler designs come from LTC Chin's book on Machine guns. I think the top design was used on the Nambu.
As for wax, wax works well, not as good a lubricant as oil, but at least it dries to a hard surface. If you remember, the Pedersen rifle required wax on the cases:had to, it was a delayed blowback.
Wax melts at the temperatures and pressures of combustion. Call it a phase change. So waxes are liquid during the pressure build up. My Garands/M1a's eject hot brass and the wax feels very slippery.
So, for things like rim fires and any cases coated in wax, when they are fired the wax melts which breaks the friction between the case and chamber. And yet, the gun does not blow up (assuming no over pressure loads)
You see, your gun was designed to carry a certain load. Bolt load was based on chamber pressure max and the surface area on the base of the cartridge. The only arguments are where to establish the surface area. You can look in the book Bolt Action by Ottesen and see how he does it.
http://www.midwayusa.com/product/37...Videos+&+Software-_-PriceCompListing-_-379313 No load calculations are based assuming any cartridge friction, no bolt is weakened assuming that the cartridge case takes any of the load.
However, exceed standard pressures by overloads, you will exceed the loads the gun was designed for, and that in time will damage your gun.