AR Caliber Conundrum

So I have a 6.8 for longer field shots and a 300 bo for creek bottom stalking. Both serve their purpose pretty well. But..I am putting together a lower and can't make up my mind on a third caliber to have. I do not reload so off the shelf ammo is important. Any suggestions and why you would choose it?

223? Cheap ammo and a hoot to shoot.

What do you want it for?

You can go with .223/5.56. With Wilde chambered barrel you can run either .223 or 5.56. Since you don't reload, ammo can be purchased economically for plinking. You can also purchase ammo suited more for hunting.

#1 223/556
#2 6.5 Grendel
I love my 6.5G but you don't have a 223/556 so I would suggest that above all else then a Grendel

To accompany what you already have, a 223 Wylde chamber in a good quality 1/8 twist barrel.

Like someone already said, it will shoot 223 or 5.56 safely.
The 1/8 twist barrel will shoot heavier bullets accurately and still do a good job with lighter bullets.
Lots of good factory ammo in that caliber.
From personal experience, the factory 69gr OTMBTs work well on whitetails.

Or, you could go big bore like 450 Bushmaster, 458 Socom, or similar.
Since you don't reload, these tend to be expensive to shoot.
Even if you do reload, they are still fairly expensive to reload.
I had a couple of 458 Socoms for a while.
They were a hoot to shoot and did the job quite well on pigs.
I cried every time I lost a piece of brass as they were only available from one source and were about a buck each.

Anybody think of the 7.62x39 round?

The 7.62 is my all around AR at the moment. Mainly because the cost of ammo.

223/556 - cheap ammo. Too light for most pigs that are running.
300 - $1 per shot
308 - $1 per shot
6.5 - $1+ per shot
7.62 - .21 per shot

I don’t feel bad when I blow thru a magazine or 2 chasing down a jackrabbit or coyote.

Keep in mind too the the lower for a 223/556 and a 300blk are interchangeable. All you need is to swap the upper and essentially have 2 guns for a reasonable price.

7.62x39 can be problematic in the AR platform.

The tapered case is hard on bolts and I've seen a few rip the lugs off the bolt, one that I was shooting.
Magazines sometimes need adjustment and can be a pain.
Not all ammo feeds reliably.
Hollow points and softtips sometimes hang up on the feed ramps and jam.

Most of the ammo is nasty and will require more cleaning but the smell of the burnt powder brings back memories.
Some of the mil-surp ammo is corrosive and requires a good cleaning.
Magazines can be adjusted pretty easily also.

Most of the ammo in this caliber has hard primers.
There are extended firing pins specifically for this cal that help quite a bit.
Since the primers are hard, even with the special firing pin, SOME light weight hammer springs just won't fire them reliably.

That being said, I do plan to build another one.

The main thing to consider is the barrel and bolt head.
Get one with a proven track record and you are GTG.
Some barrel manufacturers just screw on a .223/5.56 barrel extension with 22 cal feed ramps on a 7.62 barrel and call it good which leads to feeding problems.
The reliable ones use 30 cal extensions with wider feed ramps.

Please understand I'm not trying to put you off this caliber but make you aware of possible problems up front so you can work thru them.

To accompany what you already have, a 223 Wylde chamber in a good quality 1/8 twist barrel.
Like someone already said, it will shoot 223 or 5.56 safely.


So, if it is NOT a Wylde Chamber, it is NOT safe to shoot 223 / 5.56 ?

Paying attention to this thread. Why I'm thinking about another AR I don't really know, after a couple of months of fumbling with them in the truck I get rid of them. The 5.56 just doesn't have enough of what I want and the AR-10 is just too big and bulky. The AR platform in a 6.5 Grendel is sure getting my attention.

The Grendel and the 6.8 SPC are both bad mamma jamma's.

.224 Valkyrie

I have a couple of ARs both in 223. One is my carry duty rifle the other is my hog aka truck gun. You might consider what you want to do with this next build.

I am not a fan of 223 for deer size game in any rifle. Might consider the Grendel of you want that kinda of power for hunting. 7.62 is good also for shots out to about 100 yards. Best of luck on what you decide.

The .30 Remington AR comes to mind. Think of it as a .300 BO on steroids.

Info here: https://en.wikipedia.org/wiki/.30_Remington_AR

Factory Ammo Here: https://www.targetsportsusa.com/30-remington-ar-ammo-c-958.aspx

About $1/round or premium monolithic bullets $1.50/round

I like simplicity, I want my weapons to be in as few calibers as I need and want. I stay away from any caliber that is not a popular round and available at most retail locations. 223, 243, 270 and 308 fill all of my needs and wants, I consider anything else a "bastard" caliber that have their uses, but I don't need anymore. I used to include 30-06, but my trips to Colorado etc., ended when I "inherited" a wheelchair and a walker. I no longer need that caliber.

If I had to have only one AR-15, it would be chambered in 6.5 Grendel, zero doubt about it. I've had customers out with them, and some at our Hunter's Rifle Challenge. That cartridge with 123 gr bullets impresses me.

And if you pay attention, you can find Hornady 123 grain around $.80 /round pretty regular. And cheap wolf steel case if you want blasting ammo.

With what you already possess. I’d get a .223/5.56 or Wylde.
Pretty versatile and super cheap ammo.
I look at it as Small, Medium, Large.
You’ve got the Medium and Large.
Now get you a Small.

Appreciate the input guys. I should have stated that I don't really want another 223. Maybe I was hoping I would get talked into a 458 socom or something interesting and new. lol

ok, the .224 Valkyrie is not just another .223, shoots a 90 grain bullet effectively to 1000 yards. If looking large the .450 Bushmaster is an option with Remington factory ammo, the .458 Socom ammo is pricey, last I checked it was only loaded by Corbon. Also check out the .300 OSSM, basically a .25 WSSM with a 30 caliber bullet, pretty wicked out of an AR-15.

May research that 224 Valkyrie!

You said you don't reload.
I'm not sure that this is mainstream enough to have factory ammo yet.

If you just want something to play with, that 458 Socom is calling your name!
Or you could take up reloading, then you can really shoot what you want with ammo tailored to the task at hand.

See how we like to help folks spend their money!

And you are required to post photos of your new boom stick when finished.

It's on the shelf at Cabelas so not too hard to find now. I guess depends on how much they sell.

Valkyrie was developed by Federal so ammo should be available. Got my 20" 1:7 barrel but haven't had a chance to build the upper yet. Your 6.8 bolt and magazine will work with the Valkyrie BTW...

My buddy has an AR in 243, absolutely loves it.

Think I have settled on the 224 Valkyrie. Waiting list for an upper, no rush so I will wait. Should be a fun one to shoot and see how it performs on hogs at 8000 yd shots.

Dang it RattlesnakeDan!

You made me go look up the specs on this Valkyrie creature.
Since I am heavily invested in the 6.8 AND can use 6.8 mags and bolt face I can see this costing me money in the future!

And Palmetto has barrel/bolt combo and complete uppers in stock.
I hear the money vac coming for my wallet now....

Ammunition Depot has the 75 grain TMJ .224 Valkyrie ammo on sale for $10.99/box now, I ordered a couple for initial shooting and for the brass.....need to finish building the gun and get some reloading dies now!

.458 Socomm, Thump them hard.

Love my Grendel, but I'm a 6.5 nut! My 7.62x39 AR is my hog gun, (cheap ammo) ASC mags only!
My AR 10 (.308) has shot good groups with factory ammo, My SBR in 300 B0 suppressed kills them quietly!
BUT, my 50 Beowulf make me giggle when it thumps large hogs! A quality 5.56 is good fun also.
Luckily I didn't get into the 6.8 (not a .270 guy) Had a 300 SAUM Remington AR, but it weighted more than a scoped M1A, and ammo was Weatherby expensive!

223 good from nowhere

300 bo good from 25 yards and in

6.8spc good trajectories from 200 and in

6.5 grendel good trajectories from 400 and in

seems to me you just need to keep adding longer ranges for your AR and then you are covered for whatever you want to do

OK, I'll weigh in on this, everyone needs ONE per person in the household in 223/556. There, I said it.

Gas operated, as close to mil spec as possible,

Waiting on delivery of another 7.62x39 medium weight barrel. Everything else is in stock for another hog hammer!