accuracy ? in a 5.56

[x_wrench]

so I have had to take a break from shooting because of surgery. and with this much time just sitting around, I started wondering about the accuracy of my AR15. it has a 20" heavy barrel, and the accuracy has been ok, but not great. i am still trying to find a really good hand load for it. i have several times gotten just under moa, but nothing repeatable. i started thinking about the flash hider. the bottom port is close for obvious reasons. but I am thinking that the gas flow may not be even, kicking the bullets a bit as it leaves the barrel. has anyone tested for this? I understand that the military would be more concerned about keeping soldiers alive (breaking up muzzle flash) over loosing a bit of accuracy. it would take one cool cat to be able to shoot sub moa in a fire fight! I am thinking about getting a muzzle break and just a thread protector, because I know anything I do is going to change the barrel harmonics.

 

[redneck2]

Might try this load. 50 gr Nosler BT’s. 26.0 Varget. Federal Match primers (they’re soft, watch for slam fires). Winchester cases. 268 yards, lasered.

I’ve shot these in at least three different AR’s and all shot sub 1”. Don’t drop the bolt on a single feed round. Pick up a round from the mag or let the bolt down by hand.

 

[derek45]

A2 flash suppressor is fine.

Tell us about your accuracy loads.

hopefully, it's not cheap, crappy FMJ's ?

try a SIERRA 52gr HPBT match loaded with BLC2 or win748

that should make tiny groups in any decent rifle

 

[courtgreene]

The flash hider’s port/slot arrangement SHOULDN’T have any bearing on accuracy. If the crown behind it is off kilter, that could be doing what I imagine your concern with the flash hider is.

 

[DMW1116]

What twist rate, barrel lining, sights, and loads are you running? I use 52 grain Match Burners as well as 77 grain SMKs from a 20” chrome lined, 1/7 twist, PSA/FN barreled upper with aperture sights. The accuracy is very good but probably limited by my shooting ability and eye sight.

 

[Bfh_auto]

Definitely not the flash hider. But the crown on my Anderson looked scalloped. I recut it and found bragging groups come with 77 smk. Much cheaper nearly as accurate loads come with 52-55 grain flat based bullets

 

[12Bravo20]

What twist rate, barrel lining, sights, and loads are you running? I use 52 grain Match Burners as well as 77 grain SMKs from a 20” chrome lined, 1/7 twist, PSA/FN barreled upper with aperture sights. The accuracy is very good but probably limited by my shooting ability and eye sight.

I agree that knowing all the specs for the rifle will help us help the OP.

My Windham A2 barrel with 1-7 twist does very well even with surplus M855 ammo. Other barrels I have had to try different ammo until I found what they shot best.

 

[bfoosh006]

What brand barrel ?

No contact from the gas block at the handguard ?

Is your scopes parallax properly set ? All the scope screws properly torqued ?

Barrels bore is clean ? ( No offense intended ) Grudgingly, my best groups have been from well cleaned barrels.

 

[Nature Boy]

69 SMKs, 25.3gn Varget = sub MOA 5 shot groups for me.

I’m currently struggling a bit with heavier bullets but haven’t thrown in the towel yet.

 

[HowieG]

69 SMKs, 25.3gn Varget = sub MOA 5 shot groups for me.

I’m currently struggling a bit with heavier bullets but haven’t thrown in the towel yet.

Ditto on that brother. 69 SMK shoots great out of my Valkyrie, Heavies are merely okay.

 

[doubleh]

I have a S&W M&P that I have put a float tube on to free float the barrel and added a LaRue trigger to. I can depend on .7"-.8" inch groups at 100 yards with 60 grain Sierra hollow points and close to that with 55 grain bullets. I forget the powder charge and don't have time to go look it up now. I'm low tech and still use a pencil and notebook for data.

With 50 or 53 grain bullets the accuracy decreases and moving up to 63 grains it just falls apart. I have found Hornady v-max bullets to be almost as good as the Sierras with the same powder charge..

I use no flash hider or muzzle brake. Instead I use a 3" tube to get the noise straight in front of me. I tried a brake and the accuracy stayed the same as did the point of impact. It allowed me to see hits thru my scope but I couldn't stand the muzzle blast, especially under the low tin roof at my range.