aweful accuracy issue on new build

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[ARCHIVED THREAD] - aweful accuracy issue on new build

Posted: 9/10/2017 11:35:22 AM EDT

I have a Ruger AR556 that I have added a Rainier Arms match 223 wylde 18" 1:8 SPR barrel. I have a ALG free floating hand guard, and I have added a Geiselle SSA-E trigger. I am using a Vortex Crossfire II 4-12 power scope.

I took the rifle to a local 100yrd range, sighted in the scope with Federal Brass cased XM193 ammo. At this point I switched to Hornady 55Gr Boat Tail. The barrel was shooting between 2.5 and 4 MOA groups. This was from shooting bench using Caldwell shooting bags front and rear. Also, the rifle seemed to be short stroking as my spent casings were at about 5:00 to 5:30 position in relation to my rifle.

I HAVE checked the torque value on the scope rings and mounting screws. I took the gas block off, drew a lateral line centered over the gas port to make sure everything was lining up correctly. When I initially installed the ALG hand-guard, I watched a ton of videos and followed the instructions to a tee.

I know the Hornady ammo was not their match ammo, and I will try match ammo, but is there anything that I can do to troubleshoot?

Oh, also, I may not be the best shot, but I have had MOA and sub MOA groups with this same Lot of ammo out of my remmington 700, at this same range, with the same support bags.

Posted: 9/10/2017 11:46:52 AM EDT

[#1]

You should be able to get better groups than that.

Barrel maybe?

Posted: 9/10/2017 12:44:14 PM EDT

[#2]

just curious, but what was the accuracy of the regular Ruger barrel? I'm no expert but I don't really see how the gas block and all could be affecting accuracy once the bullet is in the chamber. Seems like that would affect reliability unless some how the tip is being deformed on the feed ramps. Does it shoot just as poorly if you put one at a time in the chamber (more like a single shot bolt action? If so, I would think you could rule out anything that has to do with feeding and cycling the bolt.

SO here are some thought from an amateur builder:
Does that barrel have some sort of "Break in procedure" that you need to follow? Are there any burrs on the new barrel crown that could be throwing it off? did you check with manufacturer and see what they think? Another thought, did you try resting the free float rail at different places? maybe somehow that affects the harmonics of the whole rifle? I don't think it should, but it might be good to rule out, maybe the handguard could be moving if the screws are working themselves loose or something- or you could try to remove the handguard and bench shoot with a front rest right up under the barrel nut.

Other than that I would have to just go with the old line that some ammo shoots better in some firearms than others... Maybe try a lighter or heavier grain bullet and see what you get. Or you could chop the top of the A2 sight off the ruger barrel and try it out with the free float. Probably the last option, but just a thought.

Posted: 9/10/2017 2:26:56 PM EDT

[#3]

I never shot the Ruger barrel for accuracy, but I did sight in the scope with it at 100 yards using the XM193 Federal. It shot reasonably tight groups though. I was just in a hurry and didn't go down range to measure.

I sold the Ruger Barrel so I can't go back and check.

Posted: 9/10/2017 2:33:43 PM EDT

[#4]

Take a look at the barrel crown for nick's,burrs,concentricity......

Posted: 9/10/2017 3:06:59 PM EDT

[#5]

Great barrels can't make bad bullets fly right. The M193 rarely shoots better than 3.5" groups at 100 yards from any of my rifles. I own Krieger, WOA, CLE, Shilen, Rock River, Colt, BCM, Douglas and probably others I can't remember, none of them will shoot that crap.

My 100% guaranteed great groups always come from 52/53 grain match bullets from any of the big three companies. Using moderate powder charges under 1" is virtually always the result. It doesn't matter what twist rate the barrel has, 100 yard groups will put a smile on your face.

FMJ bullets are the lowest quality available. They are manufactured from the nose first back to the base, exactly the opposite of match grade bullets. The only reason the military uses them is they are cheap to produce, feed reliably and have the deepest penetration. Virtually every other design is more accurate.

If you don't reload try some 52/53 grain ammo and 68/69 grain ammo. Australian Outback, Federal, Hornady and Black Hills all make decent loads for .223. Clean the barrel really well. It's new and needs a thorough cleaning.

Posted: 9/10/2017 3:07:29 PM EDT

[#6]

If you have a muzzle brake, take it off.

Posted: 9/10/2017 4:27:30 PM EDT

[#7]

Ok, I will be going back to the range sometime this week. I will take off the A2 flash hider. I assume this is to remove any inconsistencies. I will look for a 52 or 53 Gr match round from one of the brands listed. failing that, I will get whatever match grade ammo I can find locally.

As for the crown, it looks to be well machined. I inspected it when I installed it too.

Posted: 9/10/2017 7:42:07 PM EDT

[#8]

So I went to bass pro and they were our of hornady 53 gr varmint rounds so I went with a hornady 68 gr Match boat tail hollow point. I was afraid to get a 55gr because of the poor performance of the Hornady 55gr

Posted: 9/21/2017 3:12:23 PM EDT

[#9]

If you take off the flash hider to sight in, then you can't put it back on - what would be the point? If its affecting POI, you sight in with it on, then you're done. It won't cause dispersion - it will always throw the round the same way IF its affecting POI at all.

Posted: 9/22/2017 7:25:15 PM EDT

[#10]

try some heavier bullets(68-69grn), I'll bet that helps some.

Bruce

Posted: 9/24/2017 11:32:13 AM EDT

[#11]

Rainier Arms match 223 wylde 18" 1:8 SPR barrel

Production barrel, see keep in mind that it will need some live fire to unify the lands/ knock off any burs/ stress relieve the barrel until is will shoot its best.

As for pre-install, should have cleaned the barrel bore with a good copper solvent to get all the storage grease/lubes out of the bore to start with.
From here, as you are installing the barrel, moly lubed greased barrel nut and mating side of the barrel extension that that the barrel nut will bear against is tightened to 30ftlbs, loosened, retightend to 30ftlbs (to mate the barrel nut to the threads), then on the third tightening, first tightened to 35ftlbs, then rotated a max of 80ftlbs to index the gas tube channel in the barrel nut to the upper receiver barrel channel.

Next the gas block with gas tube a dry fitted to index the gas blocks channel to the barrel gas port to index them together, and using just the carrier with key (no bolt installed), the gas tube is checked for index to the carrier key, and if needed to index the gas tube to key, the gas tube is tweaked over the center of the barrel.

Once the gas tube has been correctly indexed, then the gas block with gas tube are removed, the float tube installed, then the gas block with gas tube installed.

Now the last and most important part, when the flash suppressor and break is installed, it's not over torqued to distort the last inch of the barrel bore. If you are using a crush washer, then the FS is has spun on until is finger tight, and the FS tighened via wrench less than one full turn. If you are using peel washers, then washer sections peeled off until the Fs/Brake hand tightened to index to 11:55, then wrench to 12:00. Hence more barrel has been screwed up by someone over torquing the FS/Brake than anything else, which distorts the last inch of bore!!!!

As for ammo, needs to be match type to get the most out of the barrel, and remember that that 1/8 twist barrel really needs ammo in the 62gr-69gr to shoot is best (my findings running CMP 1/8 twist barrels and dropping down from 69gr bullets for reduced target matches).

[ARCHIVED THREAD] - aweful accuracy issue on new build

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