US Troops using AK-47s

Nele VII wrote:
....
Or, if you want to believe in conspiracy theories, nobody is counting your
rounds nor the AK can be traced back to you if you whack someone by
accident... or purpose.
....

My ops sergeant once told me that in Vietnam his platoon
sergeant had kept an AK-47 for the express purpose of
shooting any of his own people who fell asleep while on
watch. Or at least he threatened to. Whether he actually
did was not clear.

From: (BUFDRVR)
Date: 7/20/2004 7:01 PM Central Daylight Time
Message-id:

The X number refers to case length. There are several 7.62 diameter rounds
out
there varying length. 30 carbine = 7.62 X 33, 30-06 = 7.62 X 63. The
Russian
equivilent to the 30-06 X 54R

Thanks to all for the answer. I'm assuming the larger x number, the longer
the
case and the longer the case the greater the load of powder?


BUFDRVR


Generally, just keep in mind the evolution of propellents so modern cartridges
can accomplish higher pressures in shorter cases. Competition shooters are
doing amazing things with ammunition now.

Dan, U. S. Air Force, retired

"B2431" wrote in message
...
|
| Generally, just keep in mind the evolution of propellents so modern
cartridges
| can accomplish higher pressures in shorter cases. Competition shooters are
| doing amazing things with ammunition now.
|
| Dan, U. S. Air Force, retired


Only up to a degree. Military ammo may have to sit on the shelf for 30
years or more (I remember shooting 50 cal that was 35 yo), be fired with
newer or older batches on the front line and be compatable with the oldest
firearms that it's likely to encounter.


The major changes were (obviously) black powder to nitrocellulose based
propellants, which would be a major advance for gas operated weapons.


Since then, most ammo development, _within a calibre_, has been for shelf
life and stability, less residue and more consistent performance
round-to-round.





Cheers


Dave Kearton

Here is a hadful from my desk drawer

www.regnirps.com/cartridges.jpg

Left to right:
..22 Long Rifle
..22 Magnum
..22 Hornet
..223 (5.56 NATO)
..243 Winchester (necked down .308 and proposed US Mil standard)
7.62mm by 39mm (AK-47, SKS, etc)
7.62mm by 51mm NATO (.308 Winchester)
30-06
..300 Winchester Magnum
..50 BMG

-- Charlie Springer

"Regnirps" wrote in message
...
| Here is a hadful from my desk drawer
|
| www.regnirps.com/cartridges.jpg
|
| Left to right:
| .22 Long Rifle
| .22 Magnum
| .22 Hornet
| .223 (5.56 NATO)
| .243 Winchester (necked down .308 and proposed US Mil standard)
| 7.62mm by 39mm (AK-47, SKS, etc)
| 7.62mm by 51mm NATO (.308 Winchester)
| 30-06
| .300 Winchester Magnum
| .50 BMG
|
| -- Charlie Springer
|
|



Nice collection, you don't have a 'still in the back yard as well ?





Cheers


Dave Kearton

Just in case you aren't confused yet, here's some more trivia. Cartridges
such as 44/40 and 45/70 come from the old black powder days. The second
part after the slash denotes how much powder was inside the casing and that
gives you the size of the casing. It sometimes helps to know the history of
the round.



Evan Williams



"BUFDRVR" wrote in message
...
The X number refers to case length. There are several 7.62 diameter
rounds
out
there varying length. 30 carbine = 7.62 X 33, 30-06 = 7.62 X 63. The
Russian
equivilent to the 30-06 X 54R

Thanks to all for the answer. I'm assuming the larger x number, the longer
the
case and the longer the case the greater the load of powder?


BUFDRVR

"Stay on the bomb run boys, I'm gonna get those bomb doors open if it
harelips
everyone on Bear Creek"

Bill Phillips
Most people use energy as a first approximation, with bullet
design just as important but harder to assess.

Bullet behaviour on impact is of decissive importance
when assessing the effectivity ("stopping power"). FMJ
7.62x39 tends to be relatively stable on impact in soft
tissue, it just turns 180 degrees to leave base first, but
does not break up nor tumble more. Thus the 7.62x39 bullet
often tends to go through the target relatively cleanly,
expending only a fraction of its energy in causing damage.

Lighter, smaller calibre, but faster, assault rifle rounds,
like 5.56x45 and 5.45x39.5, are much less stable on impact.
The higher speed and smaller diameter to lenght ratio, tends
to cause lots of tumbling in soft tissue. 5.56x45 also tends
to break up, while 5.45 with its bimetal design tends to deform.
The higher speed gives a stronger shock wave too. Thus a larger
percentage of the energy of these rounds is expanded inside the
target, causing more severe wounds at normal battlefield ranges
(at long ranges, however, the target effects are much reduced).
5.56x45 is actually _more_ effective against soft tissue at
typical ranges than slower full-sized FMJ rounds, like 7.62x51,
which tend to go through the target with much of their kinetic
energy still left. (Rifling is most relevant here too, eg 5.56
at 1:7 is more stable and less lethal on impact, than the former
standard, 1:9).

5.56 is also intrinsically better at armour penetration than
7.62x39, as the surface pressure is larger due to the smaller
calibre. Otoh, armour-piercing capability depends a lot on the
bullet design, and I dunno how the various dedicated AP bullets
compare. Full-sized rounds (7.62x51 etc) have much more kinetic
energy, and hence allow for more effective AP rounds.

5.56 and 5.45 have lower recoil than 7.62x39, allowing for
quicker/more accurate aimed rapid (semi-auto) fire and better
control of full-automatic bursts. This is a big advantage. The
recoil of 7.62x39 is however low enough for a competent user to
control an assault rifle at auto. In contrast, assault rifles with
full-sized rounds, like 7.62x51, are practically uncontrollable at
full auto. Muzzle brakes can be used to somewhat reduce the recoil,
but at a cost in the signature and/or weight and length of the
weapon.

The lethality of 7.62x39 against soft targets can be much increased
using soft point (expanding) bullets, like hunting bullets, but
these are illegal in military usage. I'd guess that a deforming
legal(?) bullet could also be developed, perhaps along the lines of
the bimetal hollow-tip FMJ 5.45x39.5. Cost would be an issue though.

7.62x39 does have an advantage over the more modern smaller
calibres though. It's less likely to be deflected by foliage,
and is also more effective when shooting through trees or berms
at a target in cover behind. I'd guess that manufacturing issues
were the historic reason why the Germans and Soviets went for 7.6*
in their AR's, rather than a faster smaller calibre round.

Full-sized rifle rounds, like 7.62x51 or 7.62x53R, typically
only have an advantage over modern assault rifle rounds at
ranges longer than normally useful for an assault rifle. The
much heavier ammunition and much larger recoil, make these
calibres badly suited for infantry assault rifles. Hence
all technically advanced armies use lighter intermediate-sized
rounds nowadays. Sniping rifles and GPMG's are another matter,
and there 7.62x51 and 7.62x53R still prevail. The particular
terrain (typical lenght of LOS) is also an issue here.

Otoh, short-barreled small-calibre carbines, like M4, have a
reduces muzzle velocity as compared to normal lenght AR's, like
the common M-16. The lower muzzle velocity of M4 impairs lethality
beyond 100m or so, which is already relevant.

Another issue is bullet drop. The faster the bullet, the less
there is bullet drop. The relatively slow 7.62x39 does particularily
badly here.the bullet drop of AKM (7.62x39) is about 70cm, which makes
adjusting the sights or aim necessary at the longer normal infantry
ranges (ie up to 300m or so). 5.56 is also superior in this respect
to the 7.62x51 at typical ranges.

(B2431) writes:
The X number refers to case length. There are several 7.62 diameter
rounds out there varying length. 30 carbine = 7.62 X 33, 30-06 =
7.62 X 63. The Russian equivilent to the 30-06 X 54R.

To confuse matters more, even the metric designations aren't
always based on the actual exact dimensions, and the same round
may have several designations. Eg, 7.62x53R and 7.62x54R are the
same round, the rimmed-cartidge (that's what the "R" stands
for) full-sized rifle found.

(B2431) writes:
The X number refers to case length. There are several 7.62 diameter
rounds out there varying length. 30 carbine = 7.62 X 33, 30-06 =
7.62 X 63.

To confuse matters more, even the metric designations aren't
always based on the actual exact dimensions, and the same round
may have several designations. Eg, 7.62x53R and 7.62x54R are the
same round, the rimmed-cartidge (that's what the "R" stands
for) full-sized rifle found.

The Japanese did this better than anyone. They had at least three 7.7 mm rifle
rounds. To be fair one was for a machine gun. The type 99 rifle used another
7.7 mm.

It's a wonder more Japanese didn't get killed or maimed by their own weapons.
The nambu sidearm was an abortion. The type 99 rifle I own was unsafe to shoot
straight from the factory; it has no noticable erosion so I slugged the barrel.
The bore is a couple thousandths too big.

Dan, U.S. Air Force, retired

From: "Evan Williams"
Date: 7/21/2004 2:53 AM Central Daylight Time
Message-id: et


Just in case you aren't confused yet, here's some more trivia. Cartridges
such as 44/40 and 45/70 come from the old black powder days. The second
part after the slash denotes how much powder was inside the casing and that
gives you the size of the casing. It sometimes helps to know the history of
the round.



Evan Williams

If you really want to confuse things bring up calibers of artillery over the
years. The 40 mm bofors and 40 mm DIVAD rounds have the same diameter, but the
lengths vary. The largest round in my collection is 105 mm in both the howitzer
(AC-130) and cannon (tank and artillery) shell lengths.

If memory serves (and it doesn't always) the 50 caliber naval round is 5 inch
diameter.

Dan, U.S. Air Force, retired