New upper build accuracy???

Discussion about rifles in 300 AAC BLACKOUT (7.62x35mm), hosted by the creator of the cartridge.

Moderators: gds, bakerjw, renegade

bdill
Silent Operator
Posts: 56
Joined: Mon Aug 25, 2014 8:32 pm

New upper build accuracy???

Post by bdill »

This is my first post but have been watching, reading, and searching for a while. I just built a new upper and it was my first build. I used a Vltor MUR upper receiver, dpms barrel nut, jp syrac adjustable gas block, and 16" carbine barrel from CMMG. I've put about 100 rounds through it so far and the best accuracy I can get with 8 round shots is 2.1" and a 5 shot group is 1.5". The was a slight wind that was going right to left was about 3 mph to as high as 10 at some times but I tried to shoot when the wind died down. I zeroed in at 75 yards and and never went further back. I stacked 4 rounds at one point and could stack 3 rounds or place them side by side but I can't get a 5 shot group below 1.5". I tried remington 125 gr match, remington 130 gr hog hammer, barnes vortex 110 gr, and remington 220 gr match. The hog hammer shot the most accurate and the barnes vortex wanted to shoot to the right a few inches. I'm disappointed in the accuracy from this build especially since I spent so much money on it. I'm building for hunting by the way. If I can't get this below an 1 consistantly then I'm gonna sell it and buy a 6.8 I guess. I went with the 300 blk out bc all you need is a barrel change but I like the power and trajectory of the 6.8. I need opinions on why my accuracy is so bad bc I would like to keep this upper. Any and all opinions are appreciated.
User avatar
smustian
Silent But Deadly
Posts: 3433
Joined: Thu Aug 08, 2013 5:55 pm
Location: Central Virginia

Re: New upper build accuracy???

Post by smustian »

If it shoots like that with factory ammo then that is not bad. Hand loads will help you achieve your desired accuracy.
rpk47
Silent But Deadly
Posts: 510
Joined: Fri Apr 25, 2014 12:33 pm

Re: New upper build accuracy???

Post by rpk47 »

What are you using for sights? Verify that whatever it is, they are secured proper and didn't come loose.
bdill
Silent Operator
Posts: 56
Joined: Mon Aug 25, 2014 8:32 pm

Re: New upper build accuracy???

Post by bdill »

I hope it gets better. I first tried a nikon buck master but the scope was having issues. So I took a scope off of a 7mm mag and put it on. I know it's true so I checked the mounts also. They are leupold mounts. Torqued the mout down onto the receiver to 60 inch pounds. Then checked alignment of scope rings. Lapped the scope rings and installed the scope. Leveled the gun and then the scope then tightened the rings to 30 inch pounds. I made sure the gaps on the rings were even an tightened them in an alternating sequence.
User avatar
rebel
Silent But Deadly
Posts: 7285
Joined: Mon Apr 22, 2013 2:01 pm
Location: Moonshine Country

Re: New upper build accuracy???

Post by rebel »

Maybe I will get a lot of flak for this - but Barnes factory Vortex ammo accuracy sucks with my rifles. To be the holy grail of performance according to some, I never had any luck with it. If you do not reload, try some Remington 125 otm match.
You can't beat the mountain, pilgrim. Mountains got its own way.
User avatar
bangbangping
Silent But Deadly
Posts: 2695
Joined: Sun Sep 15, 2013 6:34 pm
Location: Texas Gulf Coast

Re: New upper build accuracy???

Post by bangbangping »

rebel wrote:Maybe I will get a lot of flak for this - but Barnes factory Vortex ammo accuracy sucks with my rifles
You won't get any flak from me. Through a 16" Wilson Combat and a 16" AR-Stoner, the best I could get was a 3" five shot group.
bdill
Silent Operator
Posts: 56
Joined: Mon Aug 25, 2014 8:32 pm

Re: New upper build accuracy???

Post by bdill »

I ran out of of 125 gr match but the 220 gr rem seemed to be consistant if I could hold over the same amount each time. I'll try again this week if time permits. Are there any other brands I need to try for accuracy?
bdill
Silent Operator
Posts: 56
Joined: Mon Aug 25, 2014 8:32 pm

Re: New upper build accuracy???

Post by bdill »

Forgot to mention that I will be reloading soon. I need to wait until after I get married in 2 weeks to finish getting everything I need. What can I expect with reloaded ammunition. If I can get under 1 inch then I'm keeping this baby bc I would love to hunt with a suppressor since it just became legal in Georgia.
User avatar
rebel
Silent But Deadly
Posts: 7285
Joined: Mon Apr 22, 2013 2:01 pm
Location: Moonshine Country

Re: New upper build accuracy???

Post by rebel »

With 125 smk's, 17.8 gr. of w296 , coal 2.11 I shoot sub moa at 100 and 200 consistently.
You can't beat the mountain, pilgrim. Mountains got its own way.
bdill
Silent Operator
Posts: 56
Joined: Mon Aug 25, 2014 8:32 pm

Re: New upper build accuracy???

Post by bdill »

Is this with a 16" barrel? What about torquing my barrel nut? My lgs said to snug it down until my gas tube will fit correctly. I applied antiseize and tightened down the nut, but I just read somewhere to torque it 30 ft lbs then loosen, torque it to 30 ft lbs again and loosen, do it a third time and loosen, then torque to 30 ft lbs for the final tightening and advance until the gas tube notch is aligned but don't go over 80 ft lbs. Somebody else said to try a different lower. What are y'all's opinions on this?
Post Reply

Who is online

Users browsing this forum: No registered users and 158 guests