Re: New AR15 ---- I cant shoot the thing
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rrflyer</div><div class="ubbcode-body">I built up a new AR.
18" WOA 1/7 twist barrel
Troy free float rail
Standard Trigger with JP Springs
Nikon Buckmaster 4.5-14 on a PEPR Mount
I cant get consistent anything with it.
I was shooting some handloads with 69gn SMK's and 75 grain hornady match bullets over 25.3 and 24 grains of varget repectively.
By all accounts the rifle should be a shooter but I couldn't get the thing under 1.5 at 100 and consistency was all over the place. And inch or two either side of center and couldn't get a single decent grouping out of 100 rounds fired.
I even tried single loading for 6 rounds and it was still all over the place.
I was sandbagged front and rear.
So anyone have any ideas for me? I'm a little dissapointed with this thing right now.
Technique is probably a big part of it as I've never shot an AR except in competition and it was all less than 50 yard targets. </div></div>
First and foremost, congrats on your AR. I hope you followed the break-in process.
Let's address one major issue right off. Since you've NEVER fired an AR, you'll want to familiarize (conduct primary marksmanship) with iron sights before you shoot scoped with it...it's not a requirement to do this, but my military background always suggests iron sights on a battle rifle before I shoot scoped. This will give you the fundamentals of the rifle as well as develop a strong cheek-to-stock weld (positioning) so it becomes muscle-memory placement.
I'm not familiar with the barrel type you have chosen, so I have a couple of questions. Is this a heavy barrel? (this is important due to the length you chose) So we know the type of shooting, why did you go with that specific twist? Why that length of barrel?
MOST IMPORTANT: You'll want to shoot factory ammo right off for the rifle. This will give you a baseline for how it groups with certain factory loads and directs you to the load it may prefer so you're not wasting your time and/or money figuring out a hand-load. If it won't group factory ammo, there's likely a problem with the rifle...seeing as how you're getting 1 in groups at 100 yards, you're not having grouping issues indicative of a problem with the rifle platform.
Shorter barreled AR's tend to not group well, that is if you're looking for sub-moa groups at 100 yards. Rounds don't always achieve full stabilization out of true M-4 length barrels, even if you go with a fast twist which can overstabilize...give and take. It can be confounded by the lack of a heavy barrel...which ultimately allows the barrel to become hot way too fast and will throw off the accuracy as well; something that will still be present in a short heavy barrel and will usually only slightly less. ***The shorter the barrel, the more exaggerated subtle movements will become at 100 yards and beyond.
Heavier rounds will wear heavily on a barrel, even a heavy barrel. It just takes that much more uummph to get it moving.
So here's some suggestions, use them as you see fit (take them with a grain of salt).
1. Go iron sights to familiarize with the weapon...you wouldn't buy a car without a test-drive.
2. Use factory ammo to establish a base line...record it in a data book (homemade is fine if you're going to handload later).
3. After you're happy with the combat shooting, get your scope on. Work slow and keep the barrel cool. 1 shot each minute...rest between, get up, move around, whatever..just give your eyes and body a break while the rifle cools. Make sure to check your mount periodically...it could be rattling loose.
4. Once you're satisfied that it will group on factory loads and have a specific factory load it prefers, start your handloads close to that factory load.
5. You should be in the ballpark at this point, so keep logging your rounds as groups may change as the AR breaks-in more and more...not saying they will, just that they may.
Remember, battle rifles weren't designed to be sub-moa shooters. Many of the civilian versions and builds have equipment to push and redefine the limits of the AR's capabilities. If an 8 year old can take factory 55grain PMC Bronze fmj and get sub-moa groups out of my 27.5 inch Rem 700 bolt gun, then it's totally possible with other factory ammo with the right rifle set up and shooter.
Good luck testing and tuning!
