SPR / CQB one or two builds?

Broken Links

Very nice!

Wow, some great looking firearms you have there, that certainly took some money to complete.

Just one question, why didn't you go for the standard length barrel for your long-range version?

Quote:

---

Originally Posted by Cameron

You mean a 18" or 20" barrel?

They extra length doesn't provide an advantage for accuracy and the velocity loss isn't really important either.

Cameron

---

I disagree... M4 at 300 meters drops 4inches more then a M16. Though I like your build.

Very nice rifles.

The line on your BUIS; so that you tighten it to the same spot each time, or monitor if it has loosened itself? Never noticed that, just curious.

very sweet

Quote:

---

Originally Posted by Cameron

You mean a 18" or 20" barrel?

They extra length doesn't provide an advantage for accuracy and the velocity loss isn't really important either.

Cameron

---

The longer the barrel, the more accurate, the longer the range, and subsequently more lethality.

.223/5.56 is completely velocity dependent, without it, it doesn't fragment and consequently loses it's effectiveness. If I recall correctly, 5.56 has to be moving at about 2900-3000fps in order to fragment. Most carbine length barrels produce that 2900-3000fps at the muzzle, while a standard 20'' barrel does about 3100-3200.

All that extra longer range performance is worth it to me personally, even at the consequence of adding four inches to the barrel.

But to each his own, they're still nice guns either way you cut it.

Nice!

All I can say is where's the light on the Colt CQB? :D

Quote:

---

Originally Posted by foxtrot

2700 fps is about the threshold for fragmentation, but it is wholly dependant on the round. Not all 193's or SS109's fragment at all. Bullets without a cannulure probably have a very reduced chance of breaking up.

SS-109's *do* fragment like the M-193's in spite of having the penitrator.

In terms of ballistics, a M4 shooting 193's will drop below the 2700fps line before 200 yards, and a M4 shooting ss109's will drop below the 2700 fps line before 100 yards (usually about 40 yards if I remember).


*but* the chance of you having to pick off a person at 500 yards with your 16" AR is less than the chance of you winning powerball, so I'd start buying tickets. [Beer]

There is still supersonic shock even if they aren't fragmenting anyway, and for better performance you can use a vmax for all sorts of game to greatly improve the "squishy" effect. Military can't use rounds like the V-MAX so thats why fragmentation is more of an issue.

---

I was close, only 200fps off. [Coffee]

You are right though, 5.56 is a short range round by all means. Sure you can hit something at 500 yards with one, but it's effective range envelope is probably about 200-250 yards if you want to stop a man.

Either way, there's no denying a longer barrel means improved long range performance, more accuracy, etc.