Heavier bullets and the AR platform in .308?

[Trey Veston]

I bought a PSA Gen 3 upper with an 18" barrel and 1:10 twist.

Never reloaded for .308 before, but the current crisis had me scrambling for dies, cases, bullets, and primers for it.

I love accuracy. I admit it. If a hunting rifle can't do 1 MOA at 100 yards, then it is deemed unacceptable.

My rifle will be built as a plinking/range/hunting/SHTF battle rifle. So my goal is 1 MOA at 100 yards.

I bought a bunch of 150 grain target bullets, a bunch of 165 grain Horndady Interloc bullets, and some 175 grain Nosler Ballistic Tip bullets. Also have a couple of cans of Varget inbound.

I was all set to start making loads for it and then talked to my brother the other day about my new rifle. He said he has two .308s, both bolt guns, both with 1:10 twist barrels, and neither will shoot worth a darn with 150 grain loads. He said the heavier the bullet, the more accurate his rifles are.

But his rifles are bolt action with longer barrels.

Well, one is a Tikka with a 22" and the other is a Remington 700 sniper with an 18".

But, he doesn't reload. He buys factory ammo.

My question is, did I waste money on the 150 grain stuff, or have others with AR platform rifles found accuracy pretty decent with the lighter bullets?

 

[forty_caliber]

I have a custom LR-10 w/ 20" 1:10 SS bull barrel, match trigger, etc and heavier than my M1. It doesn't like the mil-spec 147 - 150gr stuff at all. It's easily 1/2 MOA with 165 - 178gr hand loads. My other two .308's (Ruger RPR, Weatherby Vanguard S2) are the same way.

That's not to say you can't hit the target at 100 yards but don't expect great groupings. This actually creates a hand loading challenge. Develop a load for 150gr equal in accuracy to the legendary 168gr BTHP round.


.40

 

[12Bravo20]

It's hard to say until you try different bullet types/weights. As we all know, each barrel will like something different.

I have a PSA PA10 Gen I with 20" stainless barrel. I shot a few boxes of Winchester 147Gr FMJ to break it in. The rifle did okay with that ammo. I next tried some Hornady American Whitetail 165Gr which shot better. I then took some Norma Tac 150Gr FMJ that shoots like a laser in my Savage but looked like a shotgun pattern out of the PA10. 168Gr and 175Gr bullets shoot better in my rifle.

 

[FL-NC]

The following rounds in 7.62 x 51 are, or have been in service for sniper rifles such as the M40 series (USMC), M24 (US Army), M21 (US Army/Navy), SR24/MK11 (SOF), and M110 (all branches):
M852 match, 168 grain- similar performance to Federal Gold Medal Match- obsolete
M118, 173 grain- obsolete
M118 LR- 175 grain open tip match- still in service
there is another designation for a newer 175 grain variant, but it escapes me now what the designation is.
The M80 ball (150 grain) which was used as a standard service rifle round for the M14, and is issued in link form for the M60 MG, the M240 MG, MK 48 MG, and others can be safely fired through all of the above rifles, but accuracy is substantially degraded in comparison to the precision rounds described above.
Another consideration is the overall length as it applies to fitting in the magazine.

 

[RainDodger]

My 1:10 AR-platform .308 absolutely loves bullets around 150 grains. In fact, it does just fine with anything 150-180. It did not seem to like it when I went lighter though, which is odd. It didn't care for some 130 grain rounds I loaded. My standard target load is a Nosler Competition, 155 gr. BTHP. It will do 1 MOA quite nicely with that round. For other uses, I have loaded 150 grain game rounds.

 

[C-grunt]

You wont get great accuracy from pinker grade 308 which is usually 145-150 grains. Just like you wont get great accuracy from 55 grain pinker grade 223.

But that has to do with loading specs and bullet design. I guarantee you could handload a MOA 150 grain load, as long as your barrel likes that bullet type.

 

[Charlie98]

You wont get great accuracy from pinker grade 308 which is usually 145-150 grains. Just like you wont get great accuracy from 55 grain pinker grade 223.

But that has to do with loading specs and bullet design. I guarantee you could handload a MOA 150 grain load, as long as your barrel likes that bullet type.

+1

A typical ~150grn FMJ bullet is not designed, nor built, for 1MOA accuracy.

My Savage bolt gun (1:10, I believe...) hates pretty much anything 150grn, even factory, but as soon as you get above 165grn... well, it's magical. If sub-MOA is your goal, you need to start with the right ingredients.

 

[jmorris]

I love accuracy. I admit it. If a hunting rifle can't do 1 MOA at 100 yards, then it is deemed unacceptable.

If you want MOA or less all day every day under all conditions and positions, you are not going to be happy.

You are going to get frustrated fairly quick trying to do it with the cheapest stuff you can buy as well.

Along those lines, I’d buy a few different premium brands of ammunition and start there as a baseline. That way you don’t go down a rabbit hole that has no reward at the end.

 

[12Bravo20]

+1

A typical ~150grn FMJ bullet is not designed, nor built, for 1MOA accuracy.

My Savage bolt gun (1:10, I believe...) hates pretty much anything 150grn, even factory, but as soon as you get above 165grn... well, it's magical. If sub-MOA is your goal, you need to start with the right ingredients.

And that is why I was pleasantly surprised that my Savage 12 shoots the Norma Tac so well. I know it isn't cheap/plinking ammo, but it isn't premium stuff either.

 

[TonyAngel]

If the barrel is at all decent, 168gr matchkings on top of varget should get you to MOA. I used winchester brass and federal BR primers.

Are you going to be single loading these or out of a magazine?

 

[MEHavey]

No problemmo....

 

[M1key]

For plinking or hunting try Hornady 150 FMJ-BT or 150 SP bullets over 27.0 gr H380. Lyman manual refers to this as an accuracy load and it shoots well for me. I believe it's a NATO equivalent load or thereabouts.

M

 

[mshootnit]

Both my AR-10s like 150 SST handloads. MOA performance. Near max load H4895 CCI BR2 primer. Bullets are seated wih a crimp at the canelure.
One of my AR10's shoots PMC XTAC Match really well the other rifle not so much.

 

[mjsdwash]

I got one hole groups at 50 yards using TNT's and H335, hardly the best combination. Same rifle. My scope does not magnify well enough for good 100 yard testing. I did shoot one 3 shot group, about 1.2", made a scope adjustment, and ran out of steam after that. FWIW, I borrowed the scope off a Savage MK in 22. A purpose made scope would certainly improve groups. I am a lousy shooter, and that trigger sucks. For fun shooting cheap, 30 Carbine bullets work in that rifle. RMR's at 2700 cycle the action, feed decent. Casual shooting got me around 2-3 at 50 yards. I'm certain a sandbag, good scope and some patience would have gotten me half that. But at 32c/round its not too bad. That TNT load costs about 36c. https://www.grafs.com/retail/catalog/product/productId/17379

 

[Trey Veston]

If the barrel is at all decent, 168gr matchkings on top of varget should get you to MOA. I used winchester brass and federal BR primers.

Are you going to be single loading these or out of a magazine?

Out of the magazine; as close to real world conditions as practical.

Using PPU brass and Winchester brass, Remington 9 1/2 primers.

 

[TonyAngel]

I was just wondering. With a bolt gun, I’ll fire form my brass to the chamber and when reloading only size enough to bump the shoulder and tighten the neck and not crimp.

This usually helps with achieving the best accuracy but, I don’t know that you can do this and still feed from the magazine with an auto.

 

[Charlie98]

only size enough to bump the shoulder

It works the same with a semi auto... but you need to make sure you bump the shoulder back enough. You do not have the mechanical leverage to get the bolt into full battery with a semi if you are also fighting to squeeze it into the chamber.

 

[Nature Boy]

Is a Nosler 175 ballistic Tip new? I thought the went from 165 to 180

 

[Trey Veston]

Is a Nosler 175 ballistic Tip new? I thought the went from 165 to 180

Yeah, I totally forgot what I had. This is what I have so far. Some more 150 grain Hornady's should be here tomorrow. Looks like I need to get some heavier bullets to try since 165 is the heaviest I have on hand.

 

[TonyAngel]

If you really want to see what it can do, load up some Berger 168gr VLDs on top of some Varget. They are expensive though.

 

[bfoosh006]

My FN CHF CL PSA upper loves the Hornady Amer. Gunner 155gr
10rds , 100yds,... tuned upper and lower.

 

[mshootnit]

Some of those longer bullets like Bergers might require a special seating stem for your die. I unpleasantly figured this out the hard way.

 

[cdb1]

I was just wondering. With a bolt gun, I’ll fire form my brass to the chamber and when reloading only size enough to bump the shoulder and tighten the neck and not crimp.

This usually helps with achieving the best accuracy but, I don’t know that you can do this and still feed from the magazine with an auto.

I’ve always heard it’s a big no-no to neck size ammunition for a semi, that it should always be full length resized. I have no hands on experience though. My son and SIL have the exact same bolt gun in 30-06. One of them likes 180 grain bullets and the other likes 150 grains. I don’t believe 150 grain bullets are inherently inaccurate in a 1:10 twist .308 AR but believe they might be in a particular rifle.

Though it’s not sexy in my experience Remington CoreLokts are accurate across a wide range of cartridges and bullet weights, so that is usually what I try first in a new rifle.

 

[Trey Veston]

Ordered a box of the Hornady ELD-X 178gr bullets at $.38 each. Expensive, but we'll see how they shoot.

 

[JDGray]

My AR-10 loved the same load my Savage bolt action liked with a Shilen match barrel, and shot it almost as well! All I did was give the ammo a bit more room with my body die, seated a bit deeper, but all else was the same. 175 gr SMKs in a 1 in 10 twist.