From a 16-inch barrel, it has more energy than 7.62 NATO has from a 22 inch barrel. It has all that energy despite having just an 80% of the cross-sectional area of 7.62 NATO. It is certain it is going to penetrate any body armor
Are US going with tungsten AP bullets? Level 4 still have a fighting chance depending on distance, angle of impact and if the armor is over spec.
I am answering this here as it’s more relevant than the QBZ191 thread.
First watch this video demonstration.
Mac is firing a 26 inch barreled 6.5mm PRC which is a close match to the 6.8x51mm round. It’s not likely that the 6.8x51mm round fired from M5, M250 or M249 will have lost much of that power at infantry combat ranges out too 300m.
Now his first shot doesn’t penetrate but it’s a lead cored copper jacketed round. Despite this It clearly does significant damage to the plate, with major back face deflation. A soldier wearing this plate is going to have at the very least the wind knocked out of him if not multiple rib fractures.
A military infantry round would likely be a steel penetrator cored copper jacketed round which would likely penetrate the armor.
If not in the first then as we see in the demonstration successive rounds. which is likely to be lethal as these plates are covering highly sensitive areas of the human anatomy. Heart, lungs, liver, spinal column. If you farther switched to a Tungsten carbide round then the plate might as well not be there.
Keep in mind that these plates are operating beyond their intended Spec, all this means that unlike today vs 5.56, 5.45x39mm, 5.8x42mm, 7.62x39, 7.62x51mm or even 7.62x54mm the chances of surviving an impact to the chest plate are no longer guaranteed. However as a rule the plate is only covering critical anatomy. It’s still possible to die by penetration into surrounding areas. Which basically means that suppression is still effective.