Useful range of 5.56, 1:7 twist, 16" barrel? (loaded question, pun intended)

[FlyFishn1]

Out of curiosity - what would be the effective/useful range of 5.56 with a 16" 1:7 twist barrel?

That is what I have so I am curious on what to expect. That wasn't picked for "long range", per se, but I wanted the faster twist rate in an attempt to get better round stability. I am just not sure what "better" means - IE - at what range will that fall off regardless?

As to the "loaded question" part - I realize the above depends highly on the load, also. At this point I am only shooting factory rounds. 62gr M855 is what I prefer at the moment. Looking at reloading it appears I can get up to the 90gr weight range also, but there are some significant drawbacks to it (can't cycle in a semi-auto, low velocity to keep the pressure in spec, etc). So that gets back to the question on useful/effective range.

 

[TargetShooter2]

depends on the Varmint your shooting & the bullet combo
but on my 16 inch barrels they are a 500 yds and in , sweet spot 200 to 350 yds for me .
TS2

 

[FlyFishn1]

Just a quick aside -

I'm looking in to the 30cal chamberings down the road as an upgrade to get more flexibility with rounds that will reach out further, but that is way down the road. I like the .308 Winchester/7.62x51 and .300 Winchester Magnum (standard, not short), but as a next step I haven't made it that far. I'm not too concerned with stretching the limit on the 5.56. I'll focus on a heavier cal later for longer range performance.

depends on the Varmint your shooting & the bullet combo
but on my 16 inch barrels they are a 500 yds and in , sweet spot 200 to 350 yds for me .
TS2

What twist rates and bullet weights are you shooting?

Do you reload? Or run factory?

 

[Elkeater]

I'm handloading 68gr Hornady boat tail hollow points. 16" barrel, 8 twist. Can't remember velocity right off hand though. I will say 600 yards is about the limit for me. Things get funny with the wind beyond that and luck starts to factor into actually hitting things.

 

[xsn10s]

I'm shooting a 75gr ELDM in my 20" AR15 2700 fps. I could get higher velocities but I'm using TAC so I'm being conservative with this winter developed load. I'll check for pressure spikes once temps get much higher. At this velocity I'll set my max at 500 yards until I see terminal performance on yotes. I'm pretty sure it'll work out to 600 yards

 

[TargetShooter2]

other than mil spec M193 & M855
I reload my own from 50,55,60 Vmax's all match bullets
from 52 grn to 77 SMK . my barrels are 1-7,1-8,1-9 twist
from 10.5 to 24 inch barrels . on 308 I load from 110 to 175 grn
on 300 WM 190 to 230 grn,
TS2

 

[Doom2]

It obviously depends on the intended use and needed terminal ballistics but a 77 SMK will stay supersonic to about 800yds when launched at 2700 fps which is about the maximum for that barrel length. The bullet hits the transonic range about at about 675 yds and 1800 fps about 420yds. Practically I would call it a 600yd rifle.

 

[ARlife4me]

7 twist will cover all weights except the 95's. However, the rpm's might destroy the bullet on the light and fast 1's. 16" will keep the velocity down which will keep the rpm's down. My 5.56 (including 223wylde) barrels all have 8 twist except 1 w/7t @ 20" barrel.

 

[xsn10s]

I shoot 53gr vmax's at 3080- 3180 fps in 20" AR15 1-7

 

[budlight]

To shoot small patterns you need good optics and something really steady shooting. Go to the range and figure out if you can shoot small groups at say 200 yards. The M855 are AP rounds. not hunting or paper rounds. If you get into reloading RMR makes great 69 hpbt that I have bought for like 14 cents each. Or even 62 hpbt or fmj for less.

To all the people that tell you they are shooting 400 -600 yards with a .223 AR I asked for a paper target proof. I probably don't even have a 50% hit rate on Prarie Dogs at 400 yards. It a small target You have to be able to shoot one inch or even sub one inch groups at 200 yards to reliably shoot small targets at 400 yards and 600 yards continues to widen that one inch at 200