AR accuracy

Red Iron

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Tried a search but I'm not sure how to word it to get results. I'm new to ARs and I'm trying to develop a load with Sierra 69gr MK for 300-600 yard shooting. I'm getting a number of 5 shot groups that have 2 shots touching then 3 more shots touching or very tight but about 3/4" vertical spread between the clusters. Overall most groups are 1 1/2" - 2" at 100yds. I'm using Varget and Re15 for powder and this seems to be happening with both. I've tried different targets to make sure I'm getting consistent holds. I've tried both a sandbag and front rest and I make sure I'm not putting pressure on the hand guard. With my bolt gun I can consistently shoot sub MOA groups so I don't think it is shooter error lol. Is this a typical problem with ARs? Is there a fix?
 
What kind of optic and ar? A good barrel, free float hand gaurd and crisp trigger are all you should need.
 
I'm running a Leupold 1.25-4 optic. Its a stock DPMS 16" carbine. The trigger sucks but I'm getting used to it. Right now I'm trying to decide between SR and CQB. I'm in the SR Clinic coming up and hope to make at least one CQB match this year and working on a load for that. If I go the SR direction I'll probably upgrade to a rifle. If I go CQB I'll probably just stick with this one and leave it stock. Maybe upgrade the trigger. In the mean time I'm just curious if this grouping issue is common to the AR platform.
 
Sounds like your rifle has great potential to shoot small groups although your trigger and 4 power scope don't help much...I bet the collapsible stock on your rig has slop on the buffer tube which will drive you nuts with vertical spread and can be dramatic depending on the amount of stock to buffer tube movement...The more slop and the further the range the more vertical you will get...A2 or Magpul PRS stocks are solid on the buffer tube and afford the best accuracy...The other thing about this type of vertical is it will more often then not be at the extremes, meaning you will get high groups and low groups depending on how you are holding the rifle.
 
1.5 to 2 MOA groups aren't unusual for a stock AR. Also a 1.25 to 4x optic may make it hard to hold a precise POA depending on the reticle. My medium barreled rifle shoots 1-1.5 MOA with Horandy 68 gn over CFE but admittedly the barrel could be better. So far, a second AR with an IUR upper is about the same but I haven't done any load development as yet.

I've seen some very accurate (sub-MOA) ARs but most are 1 to 2 MOA shooters. To get great accuracy as b_w says, I think it comes down to a great, free floated barrel, good tuned ammo and a good trigger release (this may be due to a good trigger or your skills). I've also seen suggested that a trued and more rigid upper may also help.

You might be surprised at the size of the targets in both CQB and Service Rifle...also how little bench accuracy matters versus your ability to hold the target off-hand or in position. I've been shooting more tac rifle/CQB/IPSC lately and find that the limiting factor is more me than the rifle.
 
More magnification and I bet those groups would shrink. But then you'd compromise some of the versatility of a carbine.
More magnification allows you to "aim smaller". Maybe another upper is in your future? Something with a 18-20" bbl and a higher power scope?

Edit: missed the second post about cqb/Sr. If you've got a bolt gun that shoots sub MOA perhaps leave that guy as your precision rifle and burn out the carbine as it is. 1-4 should be fine for that initially.
 
All good info guys. The optic is what I'm staying with for now. Yes there is definite slop in the stock which I try to eliminate when I shoot by using my left hand as rear bag. From my search of SR I will be fine with 1.5MOA but I'm struggling with choosing a load right now. I have one load that is about 1- 1.25" that is nice and round but those holes touching are temping lol. For CQB application I have a good load with 55gr bullets that is just over MOA so its more than good enough.
 
I'm running a Leupold 1.25-4 optic. Its a stock DPMS 16" carbine. The trigger sucks but I'm getting used to it. Right now I'm trying to decide between SR and CQB. I'm in the SR Clinic coming up and hope to make at least one CQB match this year and working on a load for that. If I go the SR direction I'll probably upgrade to a rifle. If I go CQB I'll probably just stick with this one and leave it stock. Maybe upgrade the trigger. In the mean time I'm just curious if this grouping issue is common to the AR platform.

I think you are on the right track with everything. Your rifle and optic is well suited to SR and CQB - both items are a happy medium for both sports. There are three items I'd focus on if I was in your shoes:

Trigger: change out to a Gieselle Service rifle trigger. You can always swap it out of the rifle and sell it in stock form if you ever decide to upgrade or build another AR. The Gieselle trigger is the gold standard.

Float that barrel: use a plane Jane float tube like a JP or get one with rails; it doesn't matter much which you get, but floating it does.

Ammo: I question what controls you have in place on your ammo. What is your velocity spread looking like? Runout? Are you trimming every piece of brass? All the same manufacturer of brass? Are you crimping your ammo? How are you measuring and throwing your powder charge
Nailing these down could be the difference between 1.5 and 2.5 moa groups with a 1.5moa gun.

For CQB, I get a sh!tz load of Hornady bulk 55gr FMJ, mixed brass and a decent surplus ball powder like Higginson's WC-735 and spool up the Dillon 650.
For SR and those SMKs I'd recommend one lot/make of quality brass, and individually metered powder charges.
Use 'competition' seating and FL sizing dies and spend time on brass prep.
Use a Lee Factory crimp die to crimp all of your ammo (even those SMKs, give em' a light crimp if nothing else).

There is more, but that about covers the important stuff.
 
I know this goes against what most will say but I've never used or owned a chrony. I've always just went off groups on paper. If it groups I don't care about velocity, ES, SD all that. I also am not measuring runout. I know I'm doing everything wrong lol but using the same techniques I've loaded ammo that shoots sub 1/2 MOA in rifles capable of it. I'm using Lee dies with the factory crimp die. The brass is all LC trimmed to same length. I'm weighing each charge of powder, seating to mag length. Just under 2.260". Light to moderate crimp. In my bolt gun I skip the crimp. My ammo is loaded in .2gr steps. When shooting the groups the starting loads are larger round groups that tighten to my best group then the next 2 loads were the ones that had bullets touching but the vertical spread then groups opened but went rounder again. I'm OK with 1.5" groups but teased by the potential when I see those holes touching. If I get hooked on SR the trigger upgrade and free float will be at the top of my list although probably not on this AR. Just picked this one up as a low budget way to test the waters.
 
1 to 1.5" with 69 smk is normal with run of the mill carbines. Some barrels shoot some bullets better.

If you want to have consistent 1 MOA or better result you will need a match barrel.
 
Just a quick update, loaded up a few more rounds of each load that looked like it had potential. 24.7gr Varget shot exactly like last time average 1.5" at 100yds. Looks like 24.7gr. Win 748 is the winner though, last time out it averaged 1.25" at 100yds this time just under 1". The bonus is 748 always seems to be more available in my area than Varget.
 
A good trigger will help along with good optics like a 1x8 Burris for 100 yards. The most important aspect to achieve good to very good accuracy is to shoot, shoot and shoot some more. If you are new to the AR you will find they shoot differently then anything you are accustomed to.

Once you feel comfortable you will see this rifle is very accurate by nature.
 
4x at 100yrds?! I don't think I could see the small target dots with that low mag so if I shot 1.25"-2" at 100yrds with 4x optic, I'd say that was a good day. lol
 
I typically shoot irons so 4x seems awesome lol. I do have a higher powered scope on my bolt action 223 but I haven't shot it much. This scope has a duplex crosshair reticle and it covers the dots on the targets I'm using perfectly. If I can't see any part of the dot I'm good. The reason I chose the 1.25-4 is I want it as a dual purpose carbine to try SR and CQB that power seemed to be the best of both worlds. Down the road I will change if I go SR only or CQB only. The trigger will probably have to be upgraded regardless. I'm getting more used to it but I don't like it. I honestly like a two stage military type trigger best. I like to take up the first stage as I get my breath control. I can get a great rhythm going. Are AR 2 stage triggers like that?
 
Just a quick update, loaded up a few more rounds of each load that looked like it had potential. 24.7gr Varget shot exactly like last time average 1.5" at 100yds. Looks like 24.7gr. Win 748 is the winner though, last time out it averaged 1.25" at 100yds this time just under 1". The bonus is 748 always seems to be more available in my area than Varget.

W-748 is great stuff, and it meters well! What's your barrel twist rate? W-748 and 55 gr V-Max projectiles were magic in my S&W M&P-15 (1 in 9").
 
I typically shoot irons so 4x seems awesome lol. I do have a higher powered scope on my bolt action 223 but I haven't shot it much. This scope has a duplex crosshair reticle and it covers the dots on the targets I'm using perfectly. If I can't see any part of the dot I'm good. The reason I chose the 1.25-4 is I want it as a dual purpose carbine to try SR and CQB that power seemed to be the best of both worlds. Down the road I will change if I go SR only or CQB only. The trigger will probably have to be upgraded regardless. I'm getting more used to it but I don't like it. I honestly like a two stage military type trigger best. I like to take up the first stage as I get my breath control. I can get a great rhythm going. Are AR 2 stage triggers like that?

Look into Geissele hi-speed National match trigger. There's one in the EE for 350, not sure what trigger weight it is, but for 40$ shipped you can get the various spring strengths. So I bought one that came with match Springs (3.4lb) and the service rifle springs kit to change it to 4.8lb total (3.5lb, 1.3lb). I really really like the trigger.
 
Barrel is 1:9 and the bullets I'm shooting are 69gr. MK. Thanks for the tip on the trigger. That one is probably out of my price range at this time though.
 
The Geissele triggers are awesome. I have the Hi-speed National Match in my 308 and after adjusting it to my liking then trying my buddy's SSA-E, they feel damn near identical. If you were only shooting SR, I would recommend the Hi-speed since you can tune it down to be very light. Then again, if you shoot any 3 gun type stuff, the SSA-E is non-adjustable but light and crisp enough to be super accurate. SSA-E is 2.3 lbs on the first stage and 1.2 lbs on the second
 
I guess the SSA or G2S if you went for a Geissele with a 2.5lb first and 2lb second stage.

I just picked up a TriggerTech from CanAm for $229 with free shipping. It's a single stage though but adjustable from 2-5lbs. Lower it for your precision shooting and crank it backup for your SR?
 
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