Re: Scope for an AR15
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 3PER</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rrflyer</div><div class="ubbcode-body">what are you talking about?
High power shooters a hitting moa sized targets at 600M with open sighted AR's
And you may not realize this but all guns used today are derived, one way or the other, from military arms.
The first black powder gun, lever action rifle, bolt gun, semi-auto rifle.
All original military rifles that filtered down to sportsman and shooters.
Are long shots with an AR/.223 going to be more difficult than with a higher caliber bolt gun? Yes.
But thats part of learning to shoot well, developing skill.
A .223 is cheaper to shoot, less taxing on the body and still very deadly way past what people give it credit for.
Your mentality would have everyone here shooting 300mags, 260's, or 338's because the .308 isn't very effective and becomes increasingly hard to shoot past 800 meters.
I use mine for deer, coyote, pig, varmint hunting. 3 gun/tactical matches, home defense, target punching. They make a great all around rifle.
</div></div>
5.56x45mm NATO (.223 Rem)
Back in the early days of sniper development and use for the law enforcement community the 223 Rem was fairly popular because of the fear of over penetration from the 308 Win as well as some other concerns and considerations. But as the limitations of the cartridge itself started to become known though documented engagements and other ballistic evaluations, the 223 lost favor as a sniper round. There are still cases where the .223 is used but it tends to be more as a complementary cartridge and and secondary rifle instead of being used in place of a .308 or other cartridge. The small and fragile .223 bullets, not including FMJ bullets found in most military ammunition, generally splinter on impact allowing almost no excess penetration that could possibly hit innocents, such as hostages. But with this fragmentation and lack of penetration comes a necessity for more precise shot placement and concern for insufficient penetration, leaving almost no room for error. The .223 has a small temporary wound channel (Stretch cavity), requiring almost a direct hit on the spinal stem in order to get "lights out" on a target. The lighter .223 bullet, with its low ballistic coefficient, is very susceptible to the effects of wind and loses velocity fast, which really limits its long range potential. While it is possible to achieve acceptable accuracy at 600 meters on a calm day, it is too risky on the windy days to really consider this round for military sniping purposes. Due to the lack of penetration and lack of energy, the .223 should only be used in very rare circumstances and only on head shots. There is more then one instance when a target has been shot with a perfectly placed center mass shot, and it failed to incapacitate the target. The very heavy .223 bullets (75gr +) are becoming more popular in long range shooting, but the special barrels and rifles required to shoot these high BC bullets are not available as standard sniper rifles to everyday snipers.
On the military side, the small FMJ bullets of the 223/5.56 have had their share of problems in terms of lethality. The small bullets in a full metal jacket have shown to have a tendency to pass right through their targets without doing much damage or tendency all of their energy to the target. As such the .223 has not garnered much support as a sniping caliber. But where the .223 has been fairly popular is with the Designated Marksman or Squad Advanced Marksman. These rifles tend to be similar in the standard issue battle rifles and as such the 223 is a good choice.
Note: In order to stabilize the 69-gr. Bullets and heavier, the twist on the rifle barrel needs to be at least 1:8", if you are going with 75 - 80 gr bullets you will even need a faster rate of twist such as 1:7"
Recommendation: only use the .223 within fairly short range, 100-300 meters and only take head shots if at all possible. If the .223 is all that your unit has in the way of a sniper rifle, be sure to keep in mind the limitations of the round and choose your ammunition carefully.
</div></div>
Completely agree with what he said. One thing I would like to add is, back before I knew much about ballistics I bought a bunch of 62gr green-tip M855 ammo and figured it would be even deadlier out of my M4 vs. 55gr. Not so. The 55gr FMJ will tumble which creates a worse wound cavity but the velocity of a 62gr M855 coming out of a 14.5" barrel isn't enough to cause it to tumble. The 62gr M855 needs a longer barrel. So basically I have 200 rounds of ammo I keep in my 20" AR in case I gotta fire through a car door or something fun like that
If you want to fuck something up at those ranges, a higher grain bullet is needed, but use a ballistic tip or HP.
