Best ammo for 1x9 twist, 20inch, 5.56mm

[callmecolt]

Everyone,

New to the forum, and shooting with high power scopes. I have a well build AR15 with a 20 inch barrel. Has 1x9 twist. Was looking for advice on what is the best ammo and/or load everyone has used to get the best groups?

Currently, I have been shooting PPU 5.56 62 grain green tip and I get about a 1.5in group @ 100 yards on a good day of shooting.

Thank you in advance!

 

[22bd12hd]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I have had good luck with Federal Gold Medal Match 69gr for what it is worth. I shoot it out of a .223 Remington 700 LTR.

 

[bmt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Black hills 60 grain vmax blue box,

 

[no1special]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

most 1 in 9 twist barrels will shoot 75 grain hornady hp. some will shoot 75 grain amax and sierra 77 grain hp. try a box of the hornady match ammo as it works ok (not great) at 600 yards. should easily pass the ppu. as to the ppu try their 75 grain hp. works good.

 

[tullius]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Have an old NM AR I built with a 1/9 twist, 5.56 chamber, irons of course, don't shoot it much anymore. Groups best with 69gr. handloads, but groups nearly just as well with PRVI PARTIZAN 62gr. or 69gr. factory loads. Factory 55gr. PMC were sub par.

Why don't I shoot it much anymore? Went to a 1/8 twist build, shoots a 75 gr. Hornady BTHP handload lights out..

 

[splean]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I have a 20" upper that shoots 52gn SMKs very well, about 1/2". It also shoots 69gn SMKs very well. These were both hand loads. If you plan to shoot at longer ranges the 69SMK would be a good choice or heavier if the rifle "likes" them. I don't shoot it anymore as I have switched to a 20" WOA SDMR based upper. Good luck and keep us posted.

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Thank you everyone for the input! Wide range of choices here. I soon plan to buy a few boxes of the suggested above, and take some time at the range to see what my rifle likes best. Also, I plan to make some hand loads with a friend who makes many for his higher caliber rifles.

 

[Pusher591]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Hornady 75 bthp T2. It's loaded to 5.56 pressure with crimped primers for use in semi auto platforms.

It has shot great in my 1-9 twist, but make sure it's the T2 load because the 223 load will not stabilize.

 

[GlockandRoll]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Do you know what chamber you have, 5.56, wylde, .223?
Is it chrome-lined?
Free-floated or A2 config?

 

[SGT TickleFight]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

My 1:9 does not stabilize 75gr. It loves 70gr berger handloads, though.

I shoot in oregon close to sea level so there is usually a good amount of moisture in thick air.

If you want to make sure your bullets will stabilize properly in your 1:9 i wouldn't shoot anything heavier than 70gr. Many people have success with heavier bullets but they may be marginally stabilized which can yield highly inconsistent results.

My rifle will shoot sub-moa with prvi 69gr bthp match.

 

[wyobill]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

try federal 69 gr gmm,m855 has never been noted for match accuracy.

 

[splean]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Out of curiosity what type of trigger and barrel do you run in your rifle? You might be able to squeeze some more accuracy out of your rifle with a different trigger/barrel combo. This could be an expensive route but I just thought I would ask in order to get a better idea of your rifle. You should see a difference in switching ammo alone as the M855 green tip stuff was not designed for accuracy.

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I have the Rock River 2 stage trigger with a DPMS 20inch barrel chambered in 5.56mm. The barrel is not the best, I know.

If I was to change the barrel out, I would go to 6.8 and get a new bolt face.

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I have heard this before as well. Was thinking something around a 69gr. Plan to take what everyone here has told me and buy a few boxes and see how it goes. Plan to report back with the info!

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I got to the range today. Shot a few different types of ammo. 10 rounds each. PPU M855 62Gr, Hornady Match 75Gr BTHP, PPU Match 69Gr BTHP, Black Hills Ammunition Match 52 Gr HP, and American Eagle 55Gr FMJ. Overall, it seemed to be a tie between the PPU Match and Hornady Match. I am not the best shooter, so I take that into account. I took some pictures of my targets, and my shooting setup.

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3087&d=1334534747[/img]

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3088&d=1334534750[/img]

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3089&d=1334534753[/img]

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3090&d=1334534756[/img]

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3091&d=1334534759[/img]

[img:center]http://www.acrforum.com/forum/attachment.php?attachmentid=3092&d=1334534762[/img]

 

[splean]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

Callmecolt, I can't seem to access the photos of the groups. Clicking on the links re-routes to another forum sign in page. If it's a tie between the 69gr and 75gr bullet try shooting further out. If convention holds true the 75gr should take you out further.

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

I was using the pictures off of the ACR Forum that I uploaded them too since I can't seem to find the upload tool here. Is there not one?

 

[callmecolt]

Re: Best ammo for 1x9 twist, 20inch, 5.56mm

My next test is going to be making some hand loads.