Noveske 16" Recon barrel accuracy
Hello Bananas,
Because I have a rifle with same barrel, I would suggest the following. Like some others have commented, first try to pick-up an assortment of ammo. Like any other gun, some barrels will group better with other/ different brands of ammo.
Case in point, my rifle shoots almost one ragged hole with the Hornandy FTP TAP round (55, 60, 75).
If you want to check for the true accuracy of the barrel, get match ammo, and a high powered scope (10X plus) for shooting at 100 yards.
Take a look through the search function for member Molon's posts. He is very meticulous in his accuracy testing. Check-out his equipment used and try to follow-suit. He is fairly detailed as to the conditions and equipment used.
My General (Amateur) thoughts on shooting for Accuracy;
1. Double-check again that the scope is properly mounted into the mount and that the scope tube/reticle is centered in relation to the line of bore (your cross-hair is straight in line and not off-center).
2. Use Blue or Green loctite on all of your screws for the mounting hardware.
3. Sand bags work pretty well and are inexpensive.
-As an idea, I bought Shooters Ridge Brand bags and filled them-up with Airsoft BBs and it works pretty well. Cost for both a front bag and rear (Ears) bag was around $60.00 and $8.00 for the BBs at Walmart.
4. Higher-Powered Scope. I think that a 9 power scope will do a good job at 100 yards, but for true accuracy potential something like 15-20x would be better.
5. Find a comfortable position at the bench, which lessons fatigue.
6. Ensure that the rail/ forearm is resting on the front rest (bag) and not the barrel.
7. If possible, shoot earlier in the day/ morning, when there is less wind/ breeze.
8. Let the gun break-in.
If the gun is new/ fairly new, relax and take some time to learn how it shoots. If you have been shooting iron-sighted ARs for a while becoming accustomed to a scope may take some time.
If you are not a paper-puncher (bench rest shooter), then give yourself a break.;) It takes time to become familiar with a new/ newer gun.
I am no expert on the AR platform or a Bench rest/ match shooter, but I have a solid 20 years of shooting experience and can tell you that consistency and an adherence to the basic fundamentals (as cited already in the thread) of shooting will result in the best accuracy that YOU are capable with your equipment.
FWIW: Regarding the ammo, some of the most accurate ammunition (.223 Remington 55 gr FMJ) that I have fired through my Recon barrel and a .308 Winchester rifle were the bulk low-priced UMC Green box rounds. I purchased the ammo at Walmart.
SkiDevil
P.S.
If you are using regular NRA type bulls eye targets consider buying a pack of those (whatever brand) scope sight-in targets. They have 1-inch squares and lines running horizontally and vertically on the paper to help consistently hold the reticle on (centered) target.