So, I've heard that 5.45x39 doesn't fragment like 5.56 does...how does 5.45's stopping power compare?

Supposedly the 5.45s claim to fame is that it DOES NOT fragment.  But rather it bends into a cicle like shape uppon impact with flesh.  According to Salius "Sonny" Puzikas, a former spetsnaz operator and Systema Martial arts and combat instructer in the US,

"The 5.45 round represents a significant improvement over the 5.56, much of this improvement is due to the 5mm air pocket in the nose, this shifts the center of gravity to the rear of the bullet and makes for a projectle nearly a full inch in length with exelent ballistic characteristics.  Uppon impact the core slides asymetricly into the air pocket which causes an unpredictable change in the bullets path.  This change in path causes a much quicker energy dump than 5.56, resulting in much greater damage, especialy on periferal hits."

This is taken from his DVD "Beyond the Firearm" the AK-47/74 in CQB.  

The logic seems sound.  I would like to give both a try thru ballistic geletin or watermelons or something.

Besides, at 75 yards, even out of a 20 inch barrel the 5.56 wont fragment.  My best friend has been to the sandbox sevral times.  Seal Team 1 charlie platoon.  I asked him a question about lethality of the 5.56 since there has been all the hubub about problems with the M4.  His response was that 1 or 2 rounds is not usually enough to bring someone down, 3-4 is more like it with the equipment he had, but then thats a 10 inch barrel that they use.  

Awesome, thanks a bunch!

In the defense of the 5.56...this is with M855, which I believe is standard for our troops:

From a 20" barrel, it takes the 5.56 140-150 meters to drop below fragmentation range...from a 14.5", 45-50m and from an 11.5", 12-15m.

If you're smart and not in the military (I assume they REQUIRE the use of M855, not sure) using M193, the ranges are increased a pretty good deal =).

This is all from the AR15.com ammo oracle.

kool well i was partly right about the 5.56, like i said all my info about the lethality of the M4 comes from my friend's experience in the sandbox

This thread is on the internet so it must be true.

-or-

Read the Ammo Oracle.

The deer I've shot with 223 have been throughly unimpressed all good hits and all dies but they REALLY took off, none stopped under 70 yds from where they were shot I've taken 5 with the 7.62x39 all stayed within 10 yds of where they were hit but even with good shots they gaged , coughed and complained while they expired, that with the crappy hp wolf. Next year I'm gonna try some real sp winchesters I think they will do a good job just pricey.

Quoted: kool well i was partly right about the 5.56, like i said all my info about the lethality of the M4 comes from my friend's experience in the sandbox

You said your friend had a 10 inch barrel in your previous post and now your saying he had an M4.

10 inch barrel = 10 inches.
M4 barrel = 14.5 inches.

And M855, which is what our boys use, is known to not fragment at ALL out of a 10 inch barrel. If you want fragmentation from such a short barrel you usually have to go with 75 and 77 grain stuff.

the Teams use both, therefore my friend uses both, i said he carried the 10 incher in iraq.  And they dont refer to it as anything else other than an M4 in the teams, regardless of barrel length.  Im also aware that 5.56 doesnt fragment with a 10 inch barrel.  But thanks for the correction attempt.

Quoted: the Teams use both, therefore my friend uses both, i said he carried the 10 incher in iraq.  And they dont refer to it as anything else other than an M4 in the teams, regardless of barrel length.  Im also aware that 5.56 doesnt fragment with a 10 inch barrel.  But thanks for the correction attempt.

Doesnt Fragment from a 10 inch bbl?  That would depend on the Bullet type/Construction?

yes thats correct, however, with his issue ammunition it will not fragment

I've shot deer with 5.45x39mm, 5.56 and 7.62x39mm... I havent noticed a differance in the final results. All dead within a few meters of the place shot.

I do notice less recoil and muzzle rise with the 5.45x39mm and an AK-74 brake then the 5.56. This may or may not be a factor depending on the situation. I wouldnt feel uncomfortable using any of them for self defense. Even the least of them is a lot better then a pistol.

Well said.  The only reason you should be using a sidearm is to fight your way back to the rilfe you shouldnt have dropped in the first place.

The commercial lead core we shoot such as Barnaul will upset at 3-4" and continue sideways all the way through. I've shot many deer, all 100-120lbs, with results identical to .308 sp.