In no particular order, here are a few things that work for me when accuracy testing from the bench....
First, an accurate AR seems to rely on consistent harmonics. Assuming all aspects of the build are mechanically good, the shooter plays a viable part, perhaps much more so compared to shooting a bolt rifle.
Try "driving" with the offhand up front on the handguard instead of letting it "ride" underneath the buttstock. It seems to control the weapon better, enabling consistent shoulder tension and recoil reaction. (If an AR recoils differently, the POI is usually different.) If using a PRS stock, remove that pesky rail cover and let it get a better bite on the rear bag, which is helpful with the offhand up front.
Don't torque the weapon, where the front hand is pushing right and the trigger hand is pulling left (or vice versa) to get the reticle on target. Trigger hand shouldn't be doing much more than resting on the grip and making a consistent straight-back trigger pull.
Be sure to squeeze the trigger, without knowing exactly when the shot will break. This shouldn't be problematic if the rifle is solid in the bags. If it isn't solid, reposition until it is. Take your time.
Follow through with the shot. Try to see the bullet impact on target. Even if you don't see it, this mental approach can be helpful.
If you're running out of breath, and / or the reticle begins to waiver, back out and start again. Otherwise, the shot will often fly. Stopping a shot is kinda like stopping a golf shot in mid swing. It's not easy, but can be learned.
Try a bubble level on the scope or rail to prevent cant. Cant isn't necessarily bad, unless it's inconsistent (often the case). Five degrees of cant is said to have a half-moa effect on POI.
Find a factory load that the rifle likes. Usually, AA's 123gr Scenar and / or Hornday's 123gr A-max will be good potential candidates. Then, always keep a few onhand as a check gauge, for use on days when shooter or rifle don't seem to be performing up to normal standards. This applies to handloaders as well.
If using handloads, try a small tweak. For example, if you don't crimp, give the Lee FCD a try. If you do crimp, try a load without it. Or try varying bullet seating depth by 5 or 10 thousandths.
Whether using factory or handloaded ammo, realize that some bullets and powders don't play well with others. Or they take several shots for the bore to begin responding favorably. If you shoot 3 to 5 shots of one bullet-powder combo, immediately followed by a different combo, you might never see good consistent groups.
If the barrel has been performing well, but starts shooting poorly with a pet load, clean the barrel. Intervals will vary, but it should be at least 60 or 80 rounds, and could be two or three times that many. Also, a clean barrel might take a few shots to come in.
Disclaimer- I've had no formal training of any kind, and do not claim to be the originator of any of the suggested practices. But I shoot quite a bit, and these basics work for me. YMMV.
First, an accurate AR seems to rely on consistent harmonics. Assuming all aspects of the build are mechanically good, the shooter plays a viable part, perhaps much more so compared to shooting a bolt rifle.
Try "driving" with the offhand up front on the handguard instead of letting it "ride" underneath the buttstock. It seems to control the weapon better, enabling consistent shoulder tension and recoil reaction. (If an AR recoils differently, the POI is usually different.) If using a PRS stock, remove that pesky rail cover and let it get a better bite on the rear bag, which is helpful with the offhand up front.
Don't torque the weapon, where the front hand is pushing right and the trigger hand is pulling left (or vice versa) to get the reticle on target. Trigger hand shouldn't be doing much more than resting on the grip and making a consistent straight-back trigger pull.
Be sure to squeeze the trigger, without knowing exactly when the shot will break. This shouldn't be problematic if the rifle is solid in the bags. If it isn't solid, reposition until it is. Take your time.
Follow through with the shot. Try to see the bullet impact on target. Even if you don't see it, this mental approach can be helpful.
If you're running out of breath, and / or the reticle begins to waiver, back out and start again. Otherwise, the shot will often fly. Stopping a shot is kinda like stopping a golf shot in mid swing. It's not easy, but can be learned.
Try a bubble level on the scope or rail to prevent cant. Cant isn't necessarily bad, unless it's inconsistent (often the case). Five degrees of cant is said to have a half-moa effect on POI.
Find a factory load that the rifle likes. Usually, AA's 123gr Scenar and / or Hornday's 123gr A-max will be good potential candidates. Then, always keep a few onhand as a check gauge, for use on days when shooter or rifle don't seem to be performing up to normal standards. This applies to handloaders as well.
If using handloads, try a small tweak. For example, if you don't crimp, give the Lee FCD a try. If you do crimp, try a load without it. Or try varying bullet seating depth by 5 or 10 thousandths.
Whether using factory or handloaded ammo, realize that some bullets and powders don't play well with others. Or they take several shots for the bore to begin responding favorably. If you shoot 3 to 5 shots of one bullet-powder combo, immediately followed by a different combo, you might never see good consistent groups.
If the barrel has been performing well, but starts shooting poorly with a pet load, clean the barrel. Intervals will vary, but it should be at least 60 or 80 rounds, and could be two or three times that many. Also, a clean barrel might take a few shots to come in.
Disclaimer- I've had no formal training of any kind, and do not claim to be the originator of any of the suggested practices. But I shoot quite a bit, and these basics work for me. YMMV.
Drifter