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+--- Thread: Barrel, ammo, or unreasonable expectations? (/showthread.php?tid=3472)
Barrel, ammo, or unreasonable expectations? - tobnpr - 08-07-2012
My son built his Grendel about a year ago. Getting about MOA, but can't seem to get it to shoot better.
All of my research led me to the 123 Amax, because we shoot long range (600 yards). I stayed fixated on that bullet because of it's BC...
Even powder experimentation was probably too limited, Varget and 8208. We've done some pretty extensive testing with the 8208, getting best accuracy with 27 grains and about 2350 fps. 28 grains shot very slightly larger groups, but didn't get to chrono them.
The barrel is an ER Shaw (at least, that's what I'm told- AR Stoner was made by them?), 20". I know it's not "match grade", but...(?)
So, I wonder...
Every AR-15 on the internet shoots sub-minute.
Should I expect more than MOA?
Should I try pushing lighter- and lower BC- bullets faster perhaps? Maybe the 123 Amax isn't this barrel's favorite?
8208 seems to be the right powder for this round from everything I've read, but we all know every rifle's different.
I know it's impossible to know when you've wrung out every bit of accuracy, and we all keep chasing the holy grail of loads... have I done a reasonable amount, or do you think I should try some other avenues?
Given the 600 yard range, I really don't think lighter bullets would be advantageous...
Barrel, ammo, or unreasonable expectations? - rkflorey - 08-07-2012
Try the Lapua or Sierra (123's or 107/108's) and other powders before throwing in the towel. My 22" barrel is very particular and my 16" shoots everything well. I don't have a Shaw barrel so I can't throw any stones but I believe you get what you pay for and the barrel is the most important part in my opinion. 1 moa out of a basic barrel is pretty good, not that you can't get smaller groups from these barrels. You just have to work harder at finding the magic. Kevin
Barrel, ammo, or unreasonable expectations? - bwaites - 08-07-2012
AT 600 yards, a trial of the 107 Sierra or the 108 Lapua Scenar is entirely reasonable. I shoot the 107 out to 600 in F class matches. I'm trying to find a good 123 AMAX or 130 Barnes VLD load, and I've gotten decent velocity with both, just haven't found the accuracy yet that I want. Factory 123 Hornady loads shoot sub MOA for me, though.
Next, you are shooting a barrel that is essentially rack grade. 2-4 MOA is expected in rack grade barrels, and you are better than that.
Sub MOA barrels are so talked about on the internet because they are actually fairly rare. Shooting a group or two under MOA doesn't make the barrel a sub MOA barrel. Sub MOA barrels shoot sub MOA consistently, group after group. Finding the right load will help do that, but when I see guys exclaiming over the first sub MOA group, it means to me that they need to keep shooting! I have two Satern barrels, both of which have loads that shoot sub MOA, and one of those shoots the 107 into .25 MOA groups regularly. (The shooter is the biggest detriment to that action!) That said, that super accurate barrel would barely do 1 MOA Saturday with a new load shooting 130 VLD's! '
I shoot the 107 over XBR 28.5 grains.
http://www.65grendel.com/forum/showthread.php?320-New-load-with-8208-XBR&highlight=8208
Barrel, ammo, or unreasonable expectations? - kamrr4437 - 08-08-2012
Well like previously stated 1 moa is pretty good for a button barrel. I also second the get what you pay for on barrels. But i have to say for a button rifled barrel MOA isnt to shabby. It could be alot worse. Some button barrels shoot the daylights out and some wont hit the paper. Another thing is what bullets or loads work great in some guns may give you a horrible group in another. You just have to find what works best. For alot of people believe it or not it is inconsistent shooting habits. Remember the gun can always shoot better than we can
. Sounds like a pretty good barrel though.Keith
Barrel, ammo, or unreasonable expectations? - Grimmy - 08-08-2012
My AA barrel is very picky the best 123 amax combo has been with A2520 the rifle does well averaging between 3/4 to an 1 1/4 but most at an inch. If all the planets are in perfect alignment it will shoot 1/2 groups.
Barrel, ammo, or unreasonable expectations? - Rambozo - 08-08-2012
Try IMR4895 or H4895. My accuracy load is 27.7gr of IMR4895 behind the 123Amax in Wolf brass. It doesn't do nearly as well in the lapua brass.
It doesn't shoot particularly fast, but it shoots very well for me.
How much does he have down the barrel? Do you notice a distinct "cold bore" shot? I ask only because I think I tracked down a carbon fouling problem with my .308, and I question if others fail to be on top of it too. I think that "cold bore" shot is an indication that you are keeping your rifle pretty clean. If it goes away, then you might have a problem. I cleaned a massive amount of carbon from the throat area of my rifle, and accuracy seems to have came right back. I'm talking about an 88% improvement. I have to do more shooting yet to verify. I suspect that I'm not the only one with these problems though, and it can be hard to track down as patches will show clean.
The point here is, don't be afraid to clean with brushes and elbow grease, and focus on the throat.
I can't tell you the lengths I went through before finding this out.
How did I find this out? A 25 dollar usb pen camera endoscope from ebay. It allowed me to get a pretty good view of the throat area, and what I saw was white buildup ramping from the lands. I removed it, and average groups sizes have, so far, improved from 1.2 moa to .667 moa. I also noticed the return of the off "cold bore" shot.
Barrel, ammo, or unreasonable expectations? - Whelenon - 08-08-2012
I think you should throw that barrel out, or send to me and I promise to dispose of it properly.
For a button barrel MOA is reasonable but I wouldn't give up on it yet. I've got a 16" button barrel that I shot sub-moa with the Nosler 120 BT, everything else shot 1.5-2 moa. Still looking for that holy grail load/bullet combo for my rifle. Try some different bullets or powder combinations, if your getting MOA now I'm sure with more experimentation you can make improvements. If not, my original offer stands.
Barrel, ammo, or unreasonable expectations? - ss355 - 08-09-2012
I think 1 MOA for a button-rifled barrel is darned good. Sure, it doesn't look as impressive as a five-round, cloverleaf hole, but I think you're looking north of $500 for a tube alone to shoot sub-MOA groups with any consistency.
Barrel, ammo, or unreasonable expectations? - tobnpr - 08-10-2012
Thanks for the comments, guys.
Going to try some 107's...prudent thing to do. I haven't run the numbers, but seems they should be adequate to 600, provided the wind's not blowing...
I'm going to check my son's cleaning results- including the throat (good suggestion). It reminded me that we had a REAL problem with Nosler Custom Competitions- the design of the bullet ogive was such that they would not feed- even though they were identical in weight (123) to the Amax's. Scraped up a bunch of bullets, might be some crap in the chamber as a result if it hasn't been thoroughly cleaned.
Also a good excuse to go to my LGS down the street and talk to the smith there, see if he has a borescope. It would, it seems, always be helpful if we can rule out any sort of overt barrel issues. Given moa performance though, I suspect we're about where we can get with the current setup.
Part of the "problem" (if you will) is that we're primarily a long range bolt gun "family"- this is our first foray into semi's at long range- and we need to keep our expectations reasonable. Whole different animal to have a .5 moa semi, vs. a bolt gun.
Barrel, ammo, or unreasonable expectations? - ricsmall - 08-10-2012
I may have missed it, but what kind of trigger do you have? A good trigger can reduce your groups sizes by half or more. Just curious, and you may find that magic load yet. I have two bolt guns in the safe that would only shoot factory loads, when those loads were discontinued, i loaded for a year or two trying different combos, and never found anything to shoot less than moa. theyre fine for hunting, but I like drilling tiny holes.
Barrel, ammo, or unreasonable expectations? - melensdad - 08-10-2012
ricsmall Wrote:I may have missed it, but what kind of trigger do you have? A good trigger can reduce your groups sizes by half or more. Just curious, and you may find that magic load yet. I have two bolt guns in the safe that would only shoot factory loads, when those loads were discontinued, i loaded for a year or two trying different combos, and never found anything to shoot less than moa. theyre fine for hunting, but I like drilling tiny holes.Agreed regarding the trigger.
By far the best I've tried is the AR GOLD trigger. I have it on one of my guns and its simply amazing. Even the modular Timney AR15 trigger is very good. No 2 stage trigger can match either of these two modular triggers, but nothing comes close to the AR Gold
Barrel, ammo, or unreasonable expectations? - Rambozo - 08-10-2012
ss355 Wrote:I think 1 MOA for a button-rifled barrel is darned good. Sure, it doesn't look as impressive as a five-round, cloverleaf hole, but I think you're looking north of $500 for a tube alone to shoot sub-MOA groups with any consistency.
I don't think you're giving buttoned barrels enough credit.