Favorite .308 AR10 plinking/target load ?

hounddawg

New member
Never loaded for a AR10 load and I am looking for suggestions and tips. How picky are these rifles as far as powder and bullet choice. What are realistic expectations with a stock rifle as far as accuracy ? Sub 1 MOA is goal, anything tighter than that would be gravy. Would love to stretch it out to 600 and 800 if I can get 1 moa accuracy out that far.

Powders on hand are Varget and XBR 8208. Bullets on hand are 155.5 Berger full bore (100), Hornady 168 Match (200), Hornady 175 ELDX (45). Cases will be LC new pulldown. Rifle is Springfield Saint Viktor.

I also picked up a sampler bag of the Mid South 168 gn Match Burners and considering other inexpensive bullet options such as the Speer 168 gn match and Nosler 168 gn CC in blems or seconds. If necessary I will consider other more expensive bullets such as SMK's and Bergers but obviously would prefer a less expensive option.

Thanks in advance for any suggestions and tips
 

Bart B.

New member
They're no more picky than bolt guns. But their short barrel makes 1 MOA accuracy at 800 iffy, moreso with a stock commercial version. 1 MOA meaning all shots inside 8 inches. You'll need the best grade match bullets 175 gains or more shot fast enough to stay supersonic past 800 yards in a match grade rifle and barrel to shoot MOA. Imr4064 is a good powder choice

The US Army rifle team used extra hot loads shooting Berger 185 VLD bullets in the 2012 nationals setting a team record at 1000 yards with custom built AR10's in 308 Win. Primer pockets enlarged
 
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HiBC

New member
Inside 800 yds Varget and a 168 gr bullet of MK or Nosler Custom Comp quality can shoot very well out of an accurate AR-10
 

LRDGCO

Moderator
Varget and ye olde IMR4064 are hard to beat with 150 grs - 165 grs. Varget seems slightly cleaner burning. IMR4064 seems to offer a slightly wider band of accuracy (load weights) per bullet weight.
 

hounddawg

New member
Ran some numbers and took measurements and the 178's are out, too long to seat to magazine length without taking up too much case volume I think. As far as medium to long range use it depends on the velocity I get. In this test they averaged a loss of 27FPS per inch.

http://bulletin.accurateshooter.com/2015/06/308-win-barrel-cut-down-test-velocity-vs-barrel-length/

Looking at the book loads the 155.5 Bergers might be able to be stretched out to 800 pretty easy. The 168 has plenty of speed to 600. I 'll start with the 168's and Varget and see how it goes.
 

Charlie98

New member
I've got some of those Nosler 168 CC blems, they shoot very well, but I will say, at least in 2 of my rifles... the Sierra MatchKings (SMK) actually shoot a hair better. I've settled on IMR4064 as my powder of choice. I originally started with IMR4895, but it didn't really cut the mustard when I got out past 500yds.
 
If you get to long-range, the 178's will have to be singly loaded because of the magazine fit issue. But all slow fire prone target shooting that I've ever done has been by single loading. Agree with Varget and 4064. If you can't find a sweet spot with Varget, switch to the 4064. If you can find a sweet spot with Varget, it's the more temperature-stable of the two in the .308.
 

hounddawg

New member
@Charlie98 - yeah I have a mail alert at the Nosler site for the 168's if any 168 seconds or blems come available I'll be ordering 1000. Best bullet I ever shot in one of my 260's was 1000 of the Nosler 140 grain blems

@ UncleNick - yeah those 178's are long. If seated to 2.8 at least 1/4 to 3/8's inch would be past the shoulder and into the case body. Those will probably stay in the "bullet box"

@kennyfixer - I saw that thread pop back up a few days ago but did not reread the first post and missed that it was for a AR. I had actually replied to it a couple of years back when I had a .308 barrel on a tactical bolt action. Anyway thanks and it confirms that I should be able to get 2600 FPS with the 155.5's. With a G7 BC of .237 and 2600 FPS at 800 they would still be over 1300 FPS. I shot those 155.5's exclusively when I tried long range and they shot great in a 30 inch bolt gun

Thanks for the replies guys, very helpful info. I pick the rifle up today and will be hauling it to the range next week for break in
 

T. O'Heir

New member
"...Never loaded for a AR10..." Same as any other semi-auto. However, you should pick the bullet and go from there. Vs trying a bunch of same weight bullets in sampler packs. The 'Seconds' would do for plinking though. Match bullets are pricey things.
"...out to 600 and 800..." Different bullet weight. Usually 168's out to 600 and 175's past there.
"...plinking/target load..." Very different things.
"...too long to seat to magazine length..." Load 'em to 2.800" and you'll be fine. Varget max loads with a 168, 175(no 178 grain data, but you'd use 175 grain data for that odd weight anyway.) and 180 are compressed. Compression starts long before you get to the Max load.
And just to make it interesting, a 178 grain A-Max is 1.318" long. A 178 grain HPBT is 1.345" long. An ELD-M is 1.320". Which one you use might matter.
 

Bart B.

New member
When the first 30 caliber 155 grain bullets were first shot from 308 cases, 45 grains of IMR4895 easily shot them about 1/2 to 2/3 MOA 600 through 1000 yards with max loads in 30 inch barrels leaving 3000 to 3025 fps. The favorite of those shooting the best scores.

When Varget became available, 46 grains of it shot as well.

Some Palma team members worked up the first loads for 155's and IMR4064 didn't fare well. Neither did any ball powder
 

hounddawg

New member
@ T. O'Heir Apologies often times I am not clear. English is my second language , hillbilly being the first.

I should have been more precise, I have never loaded for a .308 gas gun of any type. Some .223 and a very small amount of 6.5 Grendel, boly guns make up 95% of my reloading experience. As far as picking a bullet I let the barrel pick the bullet. In the past I have owned identical .260 barrels aftermarket barrels made by the same manufacturer but with different reamers and they prefered two entirely different bullet weights

When I say target/plinking I should have been more explicit and said non match loads. This rifle will be for pure amusement and have no grand expectations of a $1200 factory stock AR-10 shooting match quality groups. It may get some hog loads developed for it down the road but for now it is just for making smoke and noise while playing with load development and seeing how close I can get the groups

Hornady 10th lists 2.800 as COL for those 178 ELD-X's and says with Accurate 2460 they got 2550 FPS from their test barrels. Making the assumption that the test barrel was 24" and also assuming that my barrel will lose 27 FPS per inch and is 8 inches shorter that would put me between 2325 and 2350 FPS at the muzzle. Even with .237 G7 BC at 800 I down to 1100 FPS. Those ELD-X's are deadly on hogs at 50 though. I bought these to load some up for the son in laws bolt gun and he got two hogs using 1 shot each last year. I might make a hog/deer load up with them later on but for now the 155.5's make a far better long range plinking load. I shot those from my 30 inch barreled bolt gun and they were great. I'll see how they shoot in this rifle but most likely I will end up with some flavor of 168 and shooting the rifle at 300 - 500 just for the fun of shooting.
 

kennyfixer

New member
@kennyfixer - I saw that thread pop back up a few days ago but did not reread the first post and missed that it was for a AR. I had actually replied to it a couple of years back when I had a .308 barrel on a tactical bolt action. Anyway thanks and it confirms that I should be able to get 2600 FPS with the 155.5's. With a G7 BC of .237 and 2600 FPS at 800 they would still be over 1300 FPS. I shot those 155.5's exclusively when I tried long range and they shot great in a 30 inch bolt gun

I checked on Berger 155.5 with BC .473 @ cost on midwayusa $45.00

I've had Hornady 150's #3037 BC .398 for awhile so to load these is brainer. COAL is 2.40 + or - with case length 2.05 + . I have the IMR 4320 now with 1st shot brass & Match LR Federal's LR-308 with 100 rounds as partially broke in by DPMS says. Looking a targets from 100 - 300 yds right now. Not many places to shoot +400.

After the Hornady 150 are shot with a accurate load I'll move to the SMK 168's.
 

hounddawg

New member
yeah those Berger 155.5s are too expensive for me to do any shooting other than match. I have a little over 100 left from when I was shooting .308 in F class so I may as well try them down the road just to see what muzzle velocity I can get. The Barnes match burner 155's look attractive with a .467 G1 BC at less than 30 cents per piece

Thanks for the input though, with the .308's long barrel life I am looking forward to experimenting with this little rifle with a variety of bullets
 

HiBC

New member
My Nosler book shows 46 gr Varget max with a 168.They show 44 gr as accuracy load.
The AR10 T we used was built with a Badger barrel. When that was used up,it was replaced with a Krieger

In that rifle,46 gr was a touch warm. Its my brother's rifle,but as I recall the load he uses is between 44 and 45 gr.
It seemed,for us,that we got better results withVarget in the "warm" zone,rather than "cool",without going "hot"

Its still a 168 at well over 2700 fps.

I'm not going to make any wild MOA claims,but I've seen it shoot typically sub 1/2 MOA at 300 yds targets
 
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