Is the 5.56 history? Will the 6.8 Rem replace it?

[berettashotgun]

Had to add this- it is along the same lines as this thread. My sweetie carries on the job- nothing serious, just guarding snot-nosed brats (well- teenage morons) and teachers from each other. She was originally qualified in a 9mm, so she is required to carry that ROUND- not the pistol she qualified with- a Glock 17. I am proud to say she can shoot ALMOST as good as Annie Oakley after 3k+ rounds each year , but she carries a concealed 45 because she can shoot it alot better( para P-12 ). Now if a female thinks more is better ( get your mind out of the gutter ) anyone who makes this decision should. There should be no reason to have to explain or justify your reasons for personal safety.

 

[Zak Smith]

Rumor on the 'cool side of the house' says that the guys who have reason for a .45 or 6mm may so be equiped on a wider scale in the future. Riflemen may get thier A4's replaced with a 6mm.

Are you saying there is ANOTHER new assault-rifle cartridge, and it is 6.0 mm ?

 

[Jeff White]

cough, cough (I never said this)

Rumor on the 'cool side of the house' says that the guys who have reason for a .45 or 6mm may so be equiped on a wider scale in the future. Riflemen may get thier A4's replaced with a 6mm.

So we take another wrong turn on the dis-information superhighway so that someone can talk smack about his favorite cartridge or talk down his least favorite....

Jeff

 

[James T Thomas]

the girl next door

Is it the Swedish round 6,5 X 55? I believe the ballistics and history both of that one would put it in consideration as a better replacement.

Why all the experimentation for something else, unless there is money to be made?

I think that something well proven is at least worthy of a look.

 

[antsi]

--------quote-----------
I keep seeing the term "cross section density" used. I don't understand what this means. Anyone care to explain? Which cross-section does it refer to, looking at the bullet nose-on, or looking at its side?

And how does this change with bullet shape anyway? Aren't the bullets basically made out of lead and have the same density thoughout, except for the jacket?
------------------------

Sectional density is the mass of the bullet distributed over its frontal area.

Think of a dinner plate coming at you, flat side towards you. Very low sectional density.

Think of a crossbow bolt, or the penetrator from a saboted AP tank gun round. Very high sectional density.

More sectional density generally means more penetration.

Given the same caliber, the only way to change sectional density is with a heavier bullet. That's why all things being equal, heavier bullets generally penetrate better if the caliber is the same.

 

[Tony Williams]

For more info on sectional density and its relationship to ballistic coefficient etc etc see this article on Basic Ballistics: http://www.quarry.nildram.co.uk/ballistics.htm

If you're interested in alternative military rifle calibres, you might also find this useful: http://www.quarry.nildram.co.uk/Assault.htm

Tony Williams: Military gun and ammunition website and discussion forum