Ammo recommendations for .556/223

[Roofuss]

Looking for ammo recommendations for a Springfield Armory SA-16A2 rifle with 20 in. barrel.
I have one on order, and most of the info regarding ammo I have found suggests with the guns twist rate of 1-7 that a heavier bullet such as 62 gr, or a bit heavier is the most accurate. Looking into buying bulk { 500 rounds } at the best price I can find locally. My long gun experience has been mostly with bolt action and singe action rifles, so this is going to be a new ball game for me. Right now, I have no real intention of reloading for it.

 

[TJm15.38]

You have a really nice rifle. Springfield Armory puts out a quality AR. I have a 20" PSA with a 1 in 7" twist 5.56 and it is accurate and reliable with all bullet weights. I like shooting the 62-grain Federal or PMC M855 green tip and PPU 69 grain match.

 

[ColbyBruce]

Though not exactly inexpensive, Federal 68 grain ammunition shoots equally well through my CZ, DPMS, Remington .223 chambered guns and my Bushmaster, S&W, and PSA 5.56x45 AR’s. These guns have 1/7”, 1/9”, 1/12” twist rates. Your rifle will differ from others, and the iron sights and quality of your vision will affect accuracy as well.

 

[Yendor357]

Generalizations exist for a reason. But every once in a while you get a gun that simply doesn’t adhere to the rule book. Case in point, I recently bought 500 77 grain Sierra Match Kings. Perfect for a rifle with a 1/7 twist. Or so I thought. I knew this Colt 6920 that I was going to run the 77s thru, was a sub MOA rifle with Nosler 55 grain Ballistic Tips and a full charge of Varget.
With 77s, I got 3 inch groups; not what I was hoping for. CFE223 produces great velocities, by the way.

You can follow the accepted guidelines. But in the end you’re going to have to shoot your new rifle. Nice choice!

 

[murphydog]

My opinion is - right now ammo is plentiful and (relatively) affordable. So I would start with buying a small supply of 5.56 mm rounds of different common bullet weights (55, 62 gr) and see if your new rifle gets along with them. Then expand your weights as needed, down to 50 and up to 77 gr. When you find a load your gun likes, buy in bulk.

As noted above, in theory a 1:7 twist barrel should work better with heavier bullets but guns don't read physics textbooks, so there's that.

 

[WR Moore]

YMMV, but the one thing you want to avoid with the 1-7 twist is thinly jacketed bullets. When we adopted the Colt 6920 we tried a Federal load with a 55 gr soft point. We soon discovered that after 20-30 rounds bullets occasionally disappeared enroute to the targets. We sent a sample gun and ammo to Federal and after some experimenting, they suggested a round with a thicker jacket.

 

[cmansguns]

Mine really likes Lake City food

My M16 clone is 20" 1:12 twist chrome lined and will eat Federal .223 Remington 55 gr. FMJ all day long, but if I'm really interested in sweet accuracy on the 200 yard reduced size zero targets, set up actually at 100 yards, then my rifle really likes "Frontier" (Lake City M193) 55 gr. FMJ BT at listed 3240 fps.

It is me with same old eyes, same open sights, same sitting at same bench, same day, same wind, etc. so a "teeny edge" seems to go to the Lake City stuff.....maybe it is the boat tail...I don't know.

Either way...tons of fun...with or without its' "father" along with a bigger boom, more expensive ammo, and a ping.

 

[Roofuss]

My opinion is - right now ammo is plentiful and (relatively) affordable. So I would start with buying a small supply of 5.56 mm rounds of different common bullet weights (55, 62 gr) and see if your new rifle gets along with them. Then expand your weights as needed, down to 50 and up to 77 gr. When you find a load your gun likes, buy in bulk.

As noted above, in theory a 1:7 twist barrel should work better with heavier bullets but guns don't read physics textbooks, so there's that.

Thats what I'm thinking as well, as the shop is somewhat low on bulk ammo right now, and awaiting a shipment. Have to see what they have on hand and go from there .

 

[mojave30cal]

Check out SGAmmo for bulk 5.56mm purchases.

 

[Roofuss]

Check out SGAmmo for bulk 5.56mm purchases.

Thanks, I will .

 

[Roofuss]

Picked up the Springfield SA-16A2 late this morning. The store has had a large ammo order on backorder for a couple weeks now. Was able to get a few 20 round boxes of factory stuff { Hornady 68 gr. and Win. 62 gr. } for right now, but the store manager said getting bulk ammo right now is tough.

 

[Claymore33]

Ammo is cheaper now , so buy 1000 rounds, then buy another 1000 in 2 months . You cannot have too much.

 

[cololab]

You might consider going to ammoseek.com and do some brand and price comparison for different bullet weights and quantities with which you can experiment.

 

[stansdds]

Every firearm is a rule unto itself. That means that the only way to find out what produces the accuracy you desire from your rifle is to test a bunch of different loads.

 

[Roofuss]

Either way...tons of fun...with or without its' "father" along with a bigger boom, more expensive ammo, and a ping.[/QUOTE]

Also have a bigger brother, a Springfield M1A tanker awaiting warmer and drier weather, lol .

 

[67tempest]

I get sub 1 MOA accuracy with my 18 inch AR, Rock River barrel, Wylde chamber, 62 grain milsurp SS109 ammo.

 

[lrrifleman]

You have received a lot of good information here.

My initial information really focuses on the question, at what distance do you plan on shooting?

When I was physically able to shoot NRA high power rifle matches across the course (200-600 yards) I shot 68/69gr HPBTs at 200 yards for offhand and sitting rapid fire, at 300 I shot 77gr HPBTs for prone rapid fire, and 78 to 85gr HPBTs for prone slow fire.

Barrel twist primarily is focused on the rifle's ability to stabilize the bullet at distance while bucking the wind. If you are shooting short distance, under 200 yards, your rifle should shoot any bullet weight decently. However, as distance increases, groups will open up faster with the lighter weight bullets. Also, with the faster twist barrel, lighter bullets at higher velocity can tend to disintegrate in flight.

 

[Yendor357]

SS109 does shoot good.
And like a previous poster, I’ve had 53 grain match bullets not reach the target because they were rotating something like 300,000 rpm, and came apart at the seams.

I’ve been shooting ARs and 223 for 40 years, and I’m still learning.

55 Full Metal Jacket stuff used to be junk. The last time I tried that, it shot real well. Go figure. Maybe manufacturing got more precise.

**If you rifle comes with a crummy trigger, get a LaRue 2S. They’re about $110, not hard to put in. Youll thank me later.

There is one style of projectile that works in just about everything is the 55 grain plastic tipped boattail. Nosler, Sierra, Hornady 55s. That’s a good place to start.

Don’t buy the cheapest thing you can find. And don’t buy a lot of anything be for you try it out.

Man, AR-15s were a fun journey. Then came the AR-10s. More fun.