In current FMJ form, 5.45x39 offers superior terminal ballistics than both M855 and M193 5.56x45. It is a long, slender bullet which does have a very small air space in the nose which deforms causing the bullet to yaw very early and violently.Since the bullet is relatively long, when it rotates the two or three times end-over-end it drastically increases wounding capability. Testing has also shown that it can make almost 90 degree turns in some media, which could make an extremity hit a fatality. Upon its inception during the Afghanistan conflict, the Red Cross protested and challenged its legality. 5.45 ammo was able to be diverted for testing and lethality claims were substantiated and it deemed legal for use, though brutal. This was the beginning of the development of "humane" bullets by some European allies.Current generation 5.45x39 bullets are a semi-armor piercing design similar to SS109. The 5.45 bullets have a lead "knocker" which slams into the base of the penetrator core at impact furthring penetration. 5.45 is a more effective than M855 5.56 not only because of superior lethality but also because it isn't dependent on a velocity threshold to fragment.
In my anectdotal experience, 5.45x39 had proven to be more lethal and more effective than several types of 5.56 bullets against Coyotes. Over a few seasons, I objectively evaluated the effectiveness of 5.56x45 BH 68grn HP against surplus 7N6*of which I was able to secure around 3k rounds*. Several hunters were involved to get an accurate spread with multiple animals and shooters. Weapons were as follows, KAC SR15 with ACOG, RRA M4gery with EoTech, DPMS AP4 with iron sights, Vector V93 with HK scope and FN FNC. The 5.45 weapon was a SAR2 with correct compensator and PSOP4, appropriatly sighted for 5.45x39. The 5.56 HP bullets were most effective exibiting several one shot kills, a few of which were head shots. Some animals required multiple shots, though no animal was hit more than 5 times before dying.*they run fast*
While the wound track was impressive and fragmentation was near total for all rounds, even when singular rounds proved enough to by lethal, only head shots dropped em' dead. Body shots were very impressive and violent, but the animals weren't typically dead before they hit the dirt.
Performance of both rounds was nearly equal and extremely impressive. The 5.45x39
consistantly out performed both 5.56 rounds. There were no head shots as distance and inferior accuracy made this nearly impossible. The maximum number of 5.45 rounds fired at one animal was 2, as this one was running, sans hind leg. Torso/flank shots proved to be dramatic and decisive.Every aminal was literally dead before they hit the ground, and this is not an exaggeration. It appeard that 1 5.45 round created a larger wound channel than two 5.56 HP's.
One animal was hit directly at the base of the tail*while moving* and inexplicably dropped dead.
Upon further examination the bullet had penetrated and deflected into the torso literally obliterating nearly every internal organ before exiting out the bottom of the belly. On a normal sized yote, the wound pattern of the surpluse 5.45 bullet was nearly the same size as the torso cavity. While the 5.56 was certainly lethal and highly effective, overall damage and gore couldn't compare to the 5.45x39. The accuracy advantage made head shots possible with the 5.56
weapons which negates bullet design, but even when solid lethal hits were made they didnt have the dramatic effect of 5.45x39. I knew 5.45 would be effective, but I didn't know it would trump the 68grn HP which is a very effective 5.56 bullet. Some contend that 75 to 77grn bullets offer
superior lethality than 5.45 bullets. Comparing an expensive HP or open tip bullet to a surplus FMJ isn't exactly apples to apples....I have all this data I am still sifting through which I am going to prepare in a organized format with pictures that I will post for everyone when I get time. This is basically a summary, surplus 5.45 causes coyotes to detonate and instantly cease life function while 5.56 68grn HP could only equal the desicive termination with head shots. Look for my complete results to be posted as soon as I can. In any event, 5.45x39 is more effective than both M193 and M855 5.56x45 bullets and its lack of recoil, flat trajectory, accuracy and low cost make it an excellent caliber to own. The only limitation on this round is the typical weapon that fires it.