do these BCG's need a "high pressure" firing pin or another way, is the firing pin hole in the bolt too small to fit a standard mil spec firing pin? — 1 Answer

In reality there is no mill spec 308 firing pin as the 308 platforms were never adopted as a common battle rifle by the military, being utilized for special applications Only, manufacturing blueprint specifications which varies depending on the manufacturer.
That being said the DPMS gen 1, is roughly 90% + of the platforms on the market.
The original DPMS 308 platform had a .080 firing pin nose,aftermarket bolt carrier group‘s for the 308 Cartridge Family ,now have much smaller firing pin noses and corresponding bolt face orifices, Due to some of the higher pressures on the firing pin nose and bolt face. I.e. 6.5 Creedmoor and similar cartridges.
Our firing pin nose is .068 will work fine for the 6.5 Creedmore and similar cartridges

It should be noted :The ArmaLite rifle (AR 10) is not compatible with the DPMS gen 1, LR 308,SR 25