The new round is made for shorter barrels. Velocity shouldn't be a problem.
Well the M855A1 was supposedly made for the M4's shorter 369mm barrel, but it still had a much lower velocity than the original M855 fired from an M16's 508mm barrel. However it is said that the M855A1 fragments more easily, so it compensates lower velocity with more lethality when striking the target. Not sure if the DPB 191 compensates the relative lower lethality of the steel core DPB 10. Based on what I know, the DPB 95 can be very lethal (similar to M855 fired from M16's 508mm barrel) when fired from a QBZ95's 460mm barrel.
@12:33-12:42: QBZ95 firing a 5.8mm round (not sure which type) piecing 11 pieces of dense wood without fragmentation
@ 12:46: QBZ95 piecing 6 pieces of dense wood after a 2A 3mm steel plate was added in front of the wood plates
@14:51: confirmed that 5.8mm round's muzzle speed is 920mps (assuming when fired from a QBZ95, based on what is shown in the CCTV documentary)
@19:10-21:35: disgusting test starts with an officer shooting a giant piece of pork with a QBZ95, results were similar to what a 5.56mm M855/M193 could do to human flesh; 1st round caused the fragmented flesh to fly 2-3 meters away (the colonel overseeing the test was grossed out...lol), the 2nd round caused a perfect bell-shaped exit wound with no flying flesh, 3rd round struck the pork's femur and caused fragmentation of the bones within the flesh
Conclusion: the original 5.8mm round could be just as deadly and nasty as the 5.56mm M855/M193, despite having a steel core. I am more interested to see what DBP 191 does. Of course, the test was conducted at a range to around 50 meters, so of course the ammo would be extremely deadly.