Noob Ar question

[kentucky_smith]

Simple really. Bought a used upper on the AR15 EE, got it in, great shape, yadayada. 16" OlyArms plinker A1-style.
No flash suppressor. Barrel doesn't have crown, has a notch around end of barrel, not threaded.

Seeing as how not having a "target crown" or any type of crown at all, what kind of flash suppressor should I get? Could really care less about supressing muzzle flash or compensating, just want it to shoot decent.

[VUPDblue]

If it were my upper, I would remove the barrel and have it sent out to either be just re-crowned, or re-crowned and threaded so that you can use any of the aftermarket flash hiders/compensators.

[hodaka]

Shoot it and see how it works. I believe I would thread it and add a flash supressor but you could crown it yourself with some valve grinding compound and a ball bearing.

[kentucky_smith]

interesting. what kind of flash suppressor did Olympic use? Like I said there's a notch about an inch from the end all the way around the barrel.

http://www.olyarms.com/?rootView=browse&view=dtl&ids=PP

it's a plinker upper

[VUPDblue]

Is it possible that this 'notch' you speak of is actually some sort of thread protector that is screwed onto the end of the barrel? I couldn't find any recent Oly barrels that were not threaded (except for the ones with the permanent FH) that were not Bull barrels. Also, I believe that the correct FH for that rifle is the standard A2 (birdcage) flash suppressor.

[HiBC]

Consider that if the bbl is right at 16 in and you face it crowning it you may go under 16 which could get you afoul of the BATF.I don't think there is much extra.
I built a bucket of parts AR with a 16 in preban Hbar Oly bbl.I was building a post-ban carbine so I turned the threads off and sweated a bushing on the little stub.It protrudes a 1/4 in or so to protect original crown.
It has a flattop upper,a rifle length freefloat forend.Swan sleeve,armalight scope mt and a 2.5-8 Leupold Mildot.Rock river trigger..1/9 twist.I use Varget and 69 gr MK's or Nos Comps.2780 fps.Groups sub MOA.
I initially made a 2 chamber comp with forward gas jets out of 8620.Gas cutting was an issue,but I cut it down to just a crown protector because it was obnoxiously loud in a shrp,nasty,way.Prairie dog buddies didn't like it.HiBC

[Ausserordeutlich]

Why on Earth would you think adding a flash suppressor to an uncrowned barrel would improve accuracy?

[fanoblack]

I'm wondering if this barrel started life as a 20 in. model? Then got cut down, that would explain the lack of crown and threads. Just a thought.

fanoblack

[Lycanthrope]

Oly "Post Ban" guns have a "notch" at the end of the barrel. It's actually a kind of groove and not just a step down at the end of the barrel. It's put there for the Oly bolt on muzzle brake/flash suppressor. Oly barrels do have a small recessed crown, but it is not as deep as what you see in a hunting rifle.

If that's what you have you can use the bolt on brake or have the barrel cut/threaded.