.308 precision discussion

The #1 community for Gun Owners of the Northeast

Member Benefits:

  • No ad networks!
  • Discuss all aspects of firearm ownership
  • Discuss anti-gun legislation
  • Buy, sell, and trade in the classified section
  • Chat with Local gun shops, ranges, trainers & other businesses
  • Discover free outdoor shooting areas
  • View up to date on firearm-related events
  • Share photos & video with other members
  • ...and so much more!
  • ras_oscar

    Ultimate Member
    Apr 23, 2014
    1,666
    I have a gas gun in .308 (AR 10). From other threads on this forum I have concluded that there are limitations on how precise I can expect it to be. Presently I am the weak link and plan to work to close up my groups. I am consistently shooting 8" groups at 100 yards. Once I close that down I plan to move out to 200 yards.

    1. How close can I reasonably expect groups at 100 yards to become in order to say I have mastered that distance and have reached the limitations of the firearm?

    2. When I move out to 200 yards, would the expected mastery group be 4X the 100 yard number( IE 2"at 100 yards=4" at 200 yards)or something else?

    3. I am also considering a .308 bolt gun in the distant future. I don't mind spending for quality but want to get my moneys worth. Any thoughts on the following 3 manufacturers for a long range target (beyond 200 yards) shooter? Savage, Remington 700, Mossberg MVP.
     

    Biggfoot44

    Ultimate Member
    Aug 2, 2009
    32,876
    Shooting methodology @ 100yds ? ie Offhand, informal rest, prone, proper benchrest, etc ?

    What size groups do you shoot with other rifles you shoot confidently ?
     

    E.Shell

    Ultimate Member
    Feb 5, 2007
    10,242
    Mid-Merlind
    Not sure where you heard your gas gun might not shoot, but if it's built for precision, it should be fine.

    A well built AR-10, properly handled, will shoot about as well as most bolt actions out there. I have seen many of them deliver 1/2 MOA and we've shot some pretty impressive groups at long range with them too, even from a 16" barrel. Maybe some of the guys who brought them to class will chime in.

    It's ALL about the quality of the build and having good ammo.
     

    Mr. Ed

    This IS my Happy Face
    MDS Supporter
    Jun 8, 2009
    7,899
    Edgewater
    I'd suggest trying as many different brands/weights of ammo as you can find. Some guns are finicky about what they like best. I was getting terrible results with mine at 100 yards off a sand bag until I asked for some help from the experts. Turned out to be mostly ammo related. YMMV
     

    E.Shell

    Ultimate Member
    Feb 5, 2007
    10,242
    Mid-Merlind
    Regarding ammo, most AR-10 style rifles will want 7.62 x 51 ammo vs .308. M118LR and FGMM 175s have been the most reliable for function and precision.
     

    armed_economist

    Active Member
    Dec 4, 2017
    429
    For bolt rifles, apparently the ones made today are all pretty accurate even at lower price points, the difference comes in fit and finish, action smoothness, etc.

    I contemplated Mossberg mvp that takes AR mags, but many say it’s got a terribly sloppy action, although very precise.
     

    Qbeam

    Ultimate Member
    Apr 16, 2008
    6,074
    Georgia
    What is the trigger on your gas gun? Stock, upgraded? There are a lot of factors that affect accuracy and precision. As Ed stated, the rifle may need tuning as well. Give us a little more details, and we may be able to help.

    Q
     

    ras_oscar

    Ultimate Member
    Apr 23, 2014
    1,666
    What is the trigger on your gas gun? Stock, upgraded? There are a lot of factors that affect accuracy and precision. As Ed stated, the rifle may need tuning as well. Give us a little more details, and we may be able to help.

    Q

    Stock Anderson Am 10, upgraded geissele SSA-E trigger. NIkon P308 scope 4-12x40 on a Nikon M308 scope mount.

    I'm shooting from a sitting position (the only position allowed at the range I frequent)

    This is my FIRST long gun, I have NO others that I can shoot reliably. I am shooting my own reloads. I can share the recipie if needed.
     

    Speed3

    Ultimate Member
    Aug 19, 2011
    7,816
    MD
    Depending on ammo, you should be able to shoot around 1-2" at 100 yards with a .308 and most factory ammo and if a precision AR10, as Ed shared, likely .5" group with match ammo.

    I am by no means an expert, but I've stayed at the holiday Inn before and willing to help if you are close to Frederick.

    My suggestion at this point, is to focus on your form and tighten the AR10 groups up prior to spending anymore money on a new rifle. I would search for all posts from E.Shell as he has forgotten more about long range shooting than most will every know and read them several times over so it sinks in.

    I would purchase some Federal Gold Medal Match 168gr bullets and see if that helps. I could be your form, or ammo or bad rifle... we can rule 2 of those out fairly quickly if you have someone else shoot your rifle and purchase the ammo.

    Good luck, it is a fun sport, let me know if you are near Frederick and if I can help I'm more than willing.
     

    DaemonAssassin

    Why should we Free BSD?
    Jun 14, 2012
    23,970
    Political refugee in WV
    E.Shell said it best and heed his advice.

    What I can add is that if you have a well built rifle, you can get sub-MOA with FGMM, even though it may have a $125 barrel that is chambered in 308 on it. But then again when I assembled it, I did lap the upper, so that may have helped somewhat. Granted when the owner of the rifle shot it for the first time, he was seeing 6-8" at 100 yards, because he hasn't shot a rifle for almost 50 years! Let's say this much. The owner of the rifle last shot a M14 in Asia, then was handed a original M16, but received no instruction on how to use it or clean it.

    Realistically, I'm in the pursuit of a accurate 308 gas gun build, of which I am already half way done. I've bounced around with barrels so much, I've decided that I'll be going with a 18" Criterion or DMPS SASS barrel for this. I'll also be adding a SLR block to if, because eventually, I'll be getting a can for it too. My goal is 1/2 MOA, but I'll be happy if I make it to 3/4 MOA for this build.

    As for gas guns in general, I know numerous AR-15's that were built with non-match parts, that shoot sub-MOA with insane consistency, that it is flat out boring to shoot them, and I know of a few that are chambered in 300BLK...
     

    Speed3

    Ultimate Member
    Aug 19, 2011
    7,816
    MD
    Stock Anderson Am 10, upgraded geissele SSA-E trigger. NIkon P308 scope 4-12x40. on a Nikon M308 scope mount.

    This is my FIRST long gun, I have NO others that I can shoot reliably. I am shooting my own reloads. I can share the recipie if needed.

    What are you hand loads? 175gr SMK, 42-43.5gr varget, 2 thousand jump?

    Is the scope tight? Just thinking outloud.
     

    DaemonAssassin

    Why should we Free BSD?
    Jun 14, 2012
    23,970
    Political refugee in WV
    Stock Anderson Am 10, upgraded geissele SSA-E trigger. NIkon P308 scope 4-12x40 on a Nikon M308 scope mount.

    I'm shooting from a sitting position (the only position allowed at the range I frequent)

    This is my FIRST long gun, I have NO others that I can shoot reliably. I am shooting my own reloads. I can share the recipie if needed.

    Given that this is your first long gun, I'd say you need more practice behind the trigger, learning the personality of the rifle. Stop shooting your reloads, get some FGMM and some cheap ammo. Use the FGMM to see what the rifle is capable of, right now. Shoot the cheap ammo to get your trigger time, in order to build up your skills. After a while, start doing load development for the rifle. Once you find the load your rifle likes, pick up with your handloads.

    Are you shooting off of sandbags, a wooden block, a backpack, your hand? Does the rifle have a free floated barrel or a standard handguard, like the M16/M4?
     

    Qbeam

    Ultimate Member
    Apr 16, 2008
    6,074
    Georgia
    Ras,


    Thanks for the info. May help the others get an idea of what you are working with. What general area are you in? There may be members that have access to other ranges.


    Q
     

    davsco

    Ultimate Member
    Oct 21, 2010
    8,607
    Loudoun, VA
    op, where are you located, what range do you hit? guessing either your form could use some improvement and/or your gear setup (scope, mount, etc) could use some attention. 8" at 100 pretty much sucks, sure someone with just a little knowledge could really help you. also, i would buy a box each of good match ammo (fed gold medal 168 and 175, hornady eldm etc) and try that. have your handloads been used in any other rifles and if so how did they do?
     

    ToolAA

    Ultimate Member
    MDS Supporter
    Jun 17, 2016
    10,499
    God's Country
    Aside from the possibility of a loose scope, Not much new advice to offer the OP above what has already been said. We’ve all been beginners at some point. I was shocked to realize how little the rifle and optics has to do with making big improvements in accuracy and precision.

    By the way I love threads like these. It’s where MDS really shines and the reason I keep participating.

    If you want to make your way east to AGC one morning I would do my best to convey the knowledge that I’ve acquired from the community here.
     

    alucard0822

    For great Justice
    Oct 29, 2007
    17,643
    PA
    E. Shell's advice is gospel. Semi-autos have more opportunities for things to be out of alignment or inconsistent, especially with cheaper models and frankenbuilds, good parts and attention to detail while building will help eliminate variables, and produce impressive groups. There are also variables from burn rates and 7.62 vs 308 chamber specs to consider, making them relatively sensitive to ammo. Have seen 5 shot groups run from 3" down to under 1" just with a powder / charge change using the same 168gr OTM bullets. Even still 8 MOA is a big group, and there are more variables you need to eliminate before getting into changing rifles. Have seen similar results from loose mounts, crappy scopes, or damaged crowns, but also unfamiliarity with a new rifle, and poor trigger control. You need to grab plenty of ammo, and a lot of targets, then eliminate variables 1 by 1, and observe the differences. Shoot from a rest or bags, make sure to take your time, and lock into a position for every shot, ask a buddy to shoot if you can. Check the optic for any loose parts, maybe swap it if you can. Practicing marksmanship, and gaining skill are separate goals from accurizing equipment. Can also try shooting at 50 yards, and see if the group shrinks significantly under 8MOA(4" at 50yds), sometimes the reticle covers too much of the target, or it's too tough to get consistent alignment. Practice trigger control, dry fire till the reticle doesn't move off target, then fire, and repeat. If nothing makes a difference, then try an ammo change, and finally get the rifle checked after all else fails. When looking into a rifle that "just doesn't shoot", I usually find the culprit to be the shooter, ammo, and gun- in that order.

    eta: 8" groups from a new shooter while sitting definitely wouldn't lead me to believe there is anything wrong with the rifle. You need more trigger time, and work on moving arms, albows and knees to get as many body parts as possible supporting each other, and the rifle itself. The trick with position shooting is to lock into a repeatable and stable posisiton, I wouldn't change anything with the rifle till you can put a couple hundred rounds through, and see if there is an improvement. You won't be able to find the difference between a .5MOA match rifle, and a 3MOA plinker with a 8MOA wobble from an unfamiliar rifle in an unsupported position.
     

    ras_oscar

    Ultimate Member
    Apr 23, 2014
    1,666
    In the beginning I struggled with the scope mount. It had some "wiggle" in it. I got a laser bore sight, dialed the turrets to zero in both directions, loosened the mount-to-rail screws, pushed it over to where the crosshairs were closest to the dot and Loctited them down. I have a bipod in the front and sandbags in the back which I use only to ensure the rifle doesn't rest on the mag when it's not in my shoulder. I am beginning to read the Army sniper field manual as to trigger and breathing techniques. I appreciate the offers to assist. I may take you up on them once the sun returns to the sky. I was really looking for some sense of how precise I could expect my rifle to be. I guess, like most things long range, the real answer is "it depends"
     

    gwchem

    Ultimate Member
    MDS Supporter
    Dec 18, 2014
    3,434
    SoMD
    OP, the best thing you can do is take someone up on their offer to meet and shoot. Give the rifle to someone who has shot 1/2 moa groups with a quality rifle and see what they can do. Likewise, take their capable, proven rifle and see what you can do. This will save you tons of time chasing.

    As for your other questions. I have a $350 ruger american that will do 1.5 moa with hunting ammo and 1 moa with match ammo off a cheap rest. You can get precise enough for long range shooting in a cheap bolt gun. Savage and Remington have great reputations, and I don't hear much about the Mossberg.
     

    antco

    Ultimate Member
    Apr 28, 2010
    7,044
    Calvert, MD
    Ras:
    Heed E.Shells advice.

    In addition, narrowing down into a precise result takes a process of elimination when you're starting at 8". Because of that, I suggest you go to another range where you can lay prone or shoot from a bench with proper front and rear rests, a known good shooter, and a quality standard of ammunition like Federal Gold Medal Match. Doing this will let you know if the rifle even shoots. Reading books and improving your technique will leave you frustrated with your progress when you're working from a difficult sitting position and shooting a rifle that can't hit shit anyway.
     

    davsco

    Ultimate Member
    Oct 21, 2010
    8,607
    Loudoun, VA
    OP, the best thing you can do is take someone up on their offer to meet and shoot. Give the rifle to someone who has shot 1/2 moa groups with a quality rifle and see what they can do. Likewise, take their capable, proven rifle and see what you can do. This will save you tons of time chasing.

    yeah, this. way better and faster then reading books etc. but also get some fed gold medal 168 and 175 to bring to the party.
     

    Users who are viewing this thread

    Latest posts

    Forum statistics

    Threads
    274,915
    Messages
    7,258,418
    Members
    33,348
    Latest member
    Eric_Hehl

    Latest threads

    Top Bottom