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Discussion Starter · #1 ·
Let's compare the Russian 5.45mm cartridge to our 5.56mm cartridge.

Velocity: The velocity of these two cartridges is nearly the same. M16's may shoot faster muzzle velocities than AK74's, but M4's shoot slower. There is not enough difference to matter.

Caliber: The actual diameter of the 5.45mm is a smidgeon smaller than the 5.56mm, but again, it's not enough to matter.

Bullet weight: The 5.45mm bullet commonly weighs about 53 grains while the 5.56mm weighs about 55 grains or 62 grains in most FMJ loadings. The weights are close enough to not matter much.

Bullet design: Here's where the difference matters. The 5.45mm bullet is about 40 percent longer than the 55 gn 5.56mm bullet. The 5.45mm is also designed with its center of balance (center of gravity, or "CG") well to the rear. This unusually rearward CG is achieved by incorporating a large air cavity over more than 1/3 of the front of the bullet. The 5.45mm bullet can also be thought of as longer and more sharply pointed than its 5.56mm counterpart.

The design of the 5.45mm bullet makes it far less stable than the 5.56mm bullet. With properly selected twists, both the 5.45mm and 5.56mm bullets can remain accurate and stable in air. Upon striking tissue, both bullets will begin to yaw, increasing the severity of the wound over that of a stable (non-yawing) bullet.

The catch here is that the longer, more rear weighted, less stable 5.45mm bullet will yaw sooner into the tissue than the 5.56mm bullet. Since the velocity at which a FMJ bullet fragments is influenced by the thickness of its jacket, the 5.45mm can be made to fragment at a lower velocity than can the 5.56mm bullet, due to the 5.45mm bullet's quicker yaw. In practice the wounds are similar.
 

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Isn't the military loading of the 5.45 considered a "penetrator" since it has a steel insert? So in effect, wouldn't the comparison be better suited to the SS109 flavoring of the 5.56?

Does the quicker destabilization of the 5.45 hinder it's capability as a penetrator round?

So in effect, if I read this right, the 5.45 could be a more effective round fired through a gun using a shorter barrel. Since it is still effective at a lower velocity then the 5.56, then the implication is that it would be a more effective round in a shorter barreled weapon. In effect, a 5.45 fired from a 16 inch barrel possibly could equal the terminal performance of a 5.56 fired from a 20 inch barrel. Or am I reading too much into that?

Hmm, so as far as the wound channel effect, what is the best? A quickly destabilized, but lower velocity bullet, or a faster stable bullet?
 

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Thanks, For The Info! G-bullet.

the goddless forces that produced this 'CRIPPELER' bullet/rifle

know exactly what THIER about.

there are are 'NO' terms, when combating an enemy , of thier stated world
domination[they, havn't just wilted, YOU KNOW!]


it is a most effecteve[S.P]h.v projectile!



RICH Z's 5.7 wundertupperware ZAPPER, falls in the same stable![with designed projo's]




if i ever start sounding like ANDY/DAVIS, it's not 'EVER' to be blamed on a

rattlesnake/price of gas/ my LOVE of hot a woman/womem's/grenades/belt-feeds blah,blah,blah,blahmaybe !



thanks.
 

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Discussion Starter · #4 ·
Rich Z said:
Isn't the military loading of the 5.45 considered a "penetrator" since it has a steel insert? So in effect, wouldn't the comparison be better suited to the SS109 flavoring of the 5.56?
The penetrator status is less important to the yawing than is the overall length and location of CG. The SS109 will yaw similar to the 55 gn FMJ 5.56mm.

Does the quicker destabilization of the 5.45 hinder it's capability as a penetrator round?
No, hard target penetration occurs over a much shorter time than does soft target penetration. With a hard target, such as steel, the bullet is probably stopped or through before yaw becomes significant. In wood, the bullet that yaws more readily will penetrate less.

So in effect, if I read this right, the 5.45 could be a more effective round fired through a gun using a shorter barrel. Since it is still effective at a lower velocity then the 5.56, then the implication is that it would be a more effective round in a shorter barreled weapon. In effect, a 5.45 fired from a 16 inch barrel possibly could equal the terminal performance of a 5.56 fired from a 20 inch barrel. Or am I reading too much into that?
That's exactly right. Since the 5.56mm has more kinetic energy the results are similar.

Hmm, so as far as the wound channel effect, what is the best? A quickly destabilized, but lower velocity bullet, or a faster stable bullet?
Both can work. The only reason that the 5.56mm is favored over the 5.45mm is political. Since the U.S. and NATO use the 5.56mm, other countries either want to be compatible, or receive their weapons/ammo from NATO members.
 

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Hmm, but wasn't the original design for the 5.56 to be fired from a barrel with a 1 in 14 twist? I believe this produced the same effect that the 5.45 has. For some reason the twist rate was increased to 1 in 12 (I believe that's what my original AR-15 has), then to a more commonly seen 1 in 9. So why did the military decide to go with a more stabilized projectile? Distance? Trying to give the 5.56 the range of the 7.62x51?

Wouldn't decreasing the twist rate for firing the longer SS109s increase that terminal effect of rapid destabilization?

As brass hammer mentioned, from what I have read about the 5.7x28 round, they are using the same basic design in that projectile. It is a penetrator that begins to tumble shortly after entering something of higher density then air. But I thought I read that the projectile was constructed with a steel tip insert and ALUMINUM as the base of the bullet. With the weight still at the tip of the bullet, then something else must be at work to destabilize the bullet other then weight realignment upon impact.
 

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Rich Z said:
Hmm, but wasn't the original design for the 5.56 to be fired from a barrel with a 1 in 14 twist? I believe this produced the same effect that the 5.45 has. For some reason the twist rate was increased to 1 in 12 (I believe that's what my original AR-15 has)........

IIRC, during the "official" adoption/testing phase of the M-16 the 1-14" twist was found not to be accurate in arctic conditions; not sure how. So they increased the tist rate to 1-12.

Maybe that was incase we ever invaded the arctic cold of NORTH Vietnam. :rolleyes:
 

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Discussion Starter · #7 ·
Rich, a SS109 fired from a 1-in-12" twist will still group into about 4 to 5 inches at 100 yards. However, a SS109 will yaw in water, tissue, or gelatin, regardless of whether the twist is 1-in-12, 1-in-9, or 1-in-7.

The details of the construction, such as the use of lead, aluminum, etc., only serve to locate the distance of the CG from the bullet's nose. The further the CG is to the rear, the quicker the bullet will yaw.

Yes, the 5.7mm bullet is an efficient design. It will yaw quickly and uses a sleek, low drag shape.
 

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so what, anyway? The commie rd precludes the use of the .22 unit, a very big loss of utitlity. The AR uses GI rd, parts, mags, the commie gun doesn't. you dontlive inRussia, the AK's safety ergo's suck, there's a lack of decent accuracy, softpoints, match ammo, drop insights, trigger pull, ambi safety, scope mount, bipod mount, concealability, threaded,short barrels, etc, etc, for the commie gun.
 

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I will have to confess something here. I don't buy guns with the intention of having THAT particular one as my SHTF sidekick. I have never bought a gun thinking about a .22 add on unit, and probably never will. In every situation I can foresee in my future, if I need a .22, I will grab a .22 rifle. Or I will have a handgun in .22 along with my rifle of choice of the moment.

I buy guns because I find them interesting and like to have them. Right now I find the 5.45x39 interesting and I will likely have a rifle that fires this cartridge pretty shortly. Along with several ammo cans full of those cartridges as well.
 

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Rich Z said:
I will have to confess something here.
I buy guns because I find them interesting and like to have them. Right now I find the 5.45x39 interesting and I will likely have a rifle that fires this cartridge pretty shortly. Along with several ammo cans full of those cartridges as well.

RIGHT ON!

any weapon system/firearm/deathray! i can get a hold of when the STHF!
will be to my liking![until, some thing better 'sprouts' up!]

but the orignal A.R.15 in 1" twist of14" barrel length,[had it's MERITS] PLENTY!!!!

it could prove GOD COMANDING [so to speak] on soft/flesh TARGETS!

THANKS. :wavey:
[and now for something,completly diffffrent]

NOT TO GET INTO THE .270/30-06 DEBATE.

but,WE[THE U.S.A!] have been held/pulled at the ankles, ,,,... for decades!

oh!the fairness of it all is finally settling on my shoulders like a soft summer rain!


YEAH! RIGHT!

the commie /godless bastards[basically blah,blah blah % of the world] finally came on line
with there own hyper .223 in "74"

i'm sorry brother ! but if i "see" anybody packin' combloc weapons..////...

they are TARGETS of free/controlled trigger squezze!

thanks. :wavey: oh!yeah! have a nice day!
 

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brass hammer said:
the commie /godless bastards[basically blah,blah blah % of the world] finally came on line
with there own hyper .223 in "74"

i'm sorry brother ! but if i "see" anybody packin' combloc weapons..////...

they are TARGETS of free/controlled trigger squezze!

thanks. :wavey: oh!yeah! have a nice day!
Just how many of those combloc weapons do you think may have been sold within the USA? Sold to someone just like you and I? If that is the only criteria you use for unrestrained firing, you may find yourself in some very deep doo-doo someday.
 

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Look for blue helmets rather than com-bloc weapons.

RIKA
 

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aint u figured it out YET, Rich? these guys insisting upon

carrying hundreds of rds of centerfire rifle ammo, and stockpilling thousands of same, are figuring on shooting at EVERYBODY.
 

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I bought a batch of Barnaul 5.45x39 ammo that was advertised as steel and lead core with a copper jacket. Come to find out, it's not. It's a copper plated steel jacket over a lead core.

How does this effect the performance of the bullet in relation to the quickness that it destabilizes upon hitting an object? Is the center of gravity more forward now and affects this comparison?
 

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Discussion Starter · #18 ·
Rich,

If the steel is replaced with lead, the weight of the bullet should be greater. The weight of a standard, steel/lead cored 5.45mm bullet is 53 grains. An all lead cored, 5.45mm bullet could also be 53 gns if the airspace were made larger. If the all lead cored bullet is 53 gns and has the same external profile as the steel/lead bullet, then it would necessarily have a shorter core and thus yaw sooner (at a shallower depth) than the normal 5.45mm bullet.

Regardless of the rapidity with which it yaws, the all lead cored bullet will be weaker and should fragment much more readily than the steel/lead cored bullet, all else being equal. For this reason, the all lead cored 5.45mm bullet will penetrate less than the steel/lead, but the all lead cored bullet should be more effective on critters.
 

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andy said:
carrying hundreds of rds of centerfire rifle ammo, and stockpilling thousands of same, are figuring on shooting at EVERYBODY.
Ok, let me surmise what you are saying:

1) not only does the choice of caliber force us to stand around in the open
2) not only does the choice of caliber force us to shoot at every noise we hear at night
3)now the qty of ammo we have forces us to shoot at everybody.

Did I miss anything?

Does anyone else think this is a silly post?

Maybe smacking a little of paranoia?

:devil:
 

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Aslan said:
Originally Posted by andy
carrying hundreds of rds of centerfire rifle ammo, and stockpilling thousands of same, are figuring on shooting at EVERYBODY.

Does anyone else think this is a silly post?
Considering that it came from the guy who thinks he's going to shoot EVERYBODY because he's too worthless to get his own gear, so he has to steal it, yes.

It's just the bargain-basement sociopath response called the "preemptive accusation". Basically, accuse others of what you're doing (planning to do, etc), to try and sneak by on your belly without anyone noticing what you're doing. Another coward's ploy.
 
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