Grendel as a Universal Infantry Cartridge

[stanc]

Not only break apart, but the lead core blows apart into a shower of dust. I think the term "lead shower" comes from the x-rays of 5.56 injuries that have been documented.

I prefer actual x-ray photos, not artist drawings, although the drawings you referenced basically represent what happens...

Judging by those pics, "lead shower" is a very apt description.

But it also brings up another point: One of your objections to replacing 5.56 NATO with 6.5 Grendel in carbines is that with a muzzle velocity of circa 2600 fps, there won't be such a "lead shower" beyond muzzle contact distance.

The trouble is, M855 is being phased out, replaced by M855A1. Since there is no lead in the M855A1 bullet, it cannot produce such a shower of tiny particles. At most there will be only a few large pieces -- the steel tip, copper slug, and jacket.

Even if a 6.5 M855A1-type bullet doesn't fragment, the greater mass and size may compensate. Plus, UK and European armies use non-fragmenting 5.56 bullets, so going to a non-fragmenting 6.5 round seems like it could only improve terminal performance for them.