Best AR general purpose caliber?

[stagpanther]

I'm done with being on the bleeding edge (aka public testers) with new cartridges. Too much garbage hype and too much incremental updates to reamer specs while trying to get it right. Let someone else kaboom themselves. I'm going to wait at least two years after it's introduced before trying anything new.

[Buckeye!]

6.5 Grendel is just a great round.. if u are a handloader … ammo just to expensive
Im a 7.62x39 .. has limitations.. as long as you know’em .. ur good to go

[rickyrick]

I also think the 5.56/.223 is as about general purpose as you can get out to 300. The cartridge is more capable than internet lore suggests.

Shorter or longer distances there may be other options.

What I’ve found is as you stray away from .223 you end up giving up something, be it:
Cost
Ammo capacity
Reliability
Ammo availability
Range
Etc

[Road_Clam]

300BO subs suppressed. NV equipped . "General purpose" all day long (and night)

[Shadow9mm]

Having just build a 6mm arc gun and having just shot it yesterday my perspective is shifting a bit. The main issue I have with it so far is ammo availability, or brass availability as I reload. 223/5.56 still has it beat hands down as far as availability goes. However I really like the way 6mm arc shoots and the extra energy and range it brings.

[rickyrick]

Just out of curiosity, how much bullet drop does subsonic 300bo have at 300yrds?

The OP wants to take game at 300yards.

[MTT TL]

300 yards hunting medium game will likely be better served with a 6.5 or 6.8 than 5.56. Either will work well at 300 yards. If you want to shoot farther, get the 6.5G with a longer barrel. Factory ammo is cheaper for the 6.5 if that matters.

Of course if you wanted to go with an AR-10 style the .277 Fury blows both of the others away with performance. With the AR-10 being a full size rifle as opposed to the lighter carbine.

[tangolima]

Originally Posted by rickyrick

Just out of curiosity, how much bullet drop does subsonic 300bo have at 300yrds?

The OP wants to take game at 300yards.

About 15 feet. Flight time is about 1 sec.

The elevation on a m16 peep sight starts at 300yd and ends at 600yd. There must be some effectiveness even for the small .223, depending on your definition.

-TL

Sent from my SM-N960U using Tapatalk

[stagpanther]

Having just build a 6mm arc gun and having just shot it yesterday my perspective is shifting a bit. The main issue I have with it so far is ammo availability, or brass availability as I reload. 223/5.56 still has it beat hands down as far as availability goes. However I really like the way 6mm arc shoots and the extra energy and range it brings.

I made my ARC brass from grendel brass, pretty straight-forward with nothing special other than watching for neck length growth and trimming it. I didn't have to do any neck turning. I have noticed that grendel brass has gone up in price (like everything else) but you can still find it--you can order it direct from starline if you don't won't to pay big bucks.The arc works well in an AR as well as bolt. If I was going bolt-only there are a few better alternatives--but it works very well in the AR but you might be limited in COL by the magazine (unless you do a front cut-out).

[TXAZ]

If the OP is worried about an ethical / high probability kill at 300 yards, consider moving to a .308.
There are many quality components / complete rifles available that are 3/4 MOA or better with factory ammo.

[Shadow9mm]

Originally Posted by TXAZ

If the OP is worried about an ethical / high probability kill at 300 yards, consider moving to a .308.
There are many quality components / complete rifles available that are 3/4 MOA or better with factory ammo.

Based on the numbers i have run, 6mm arc is generally good to between 350-500 yds, at 1800fps or more, which is generally the minimum expansion velocity for most hunting bullets

[rickyrick]

.223 does kill within the OPs range

[MTT TL]

.223 does kill within the OPs range

It does, but there are more effective options out there.

[MarkCO]

Originally Posted by MTT TL

Of course if you wanted to go with an AR-10 style the .277 Fury blows both of the others away with performance.

We kind of don't know a lot of things about the .277 Fury. I know more now with a few fired cases on my desk. But for a hunting rifle, a .270Win does make A LOT more sense with a 24" barrel than 80Kpsi with a 16" barrel.

Oh, and the OP said AR15 pattern, so the 277Fury is not even eligible for consideration.

[MTT TL]

That is why I qualified that statement.

Not sure I would favor a 24" barrel AR for HD purposes. Just doesn't seem as handy.

[rickyrick]

It does, but there are more effective options out there.

I don’t disagree at all, but I’m looking at it from a do-all caliber point of view.

I tend to assemble components into purpose made ARs.

To restate my original opinion on the topic

I also think the 5.56/.223 is as about general purpose as you can get out to 300. The cartridge is more capable than internet lore suggests.

Shorter or longer distances there may be other options.

What I’ve found is as you stray away from .223 you end up giving up something, be it:
Cost
Ammo capacity
Reliability
Ammo availability
Range
Etc
__________________

[GeauxTide]

My first AR was a Grendel. 123SST in .3".

[MarkCO]

Originally Posted by MTT TL

That is why I qualified that statement.

Not sure I would favor a 24" barrel AR for HD purposes. Just doesn't seem as handy.

AND, no way I'd pick the 16" 277 FURY for HD either.

[wild willy]

A couple years ago I would have said 6.8 SPC immediately but things have changed Sierra has discontinued bullets other bullets are impossible to get.The cheap overrun/surplus ammo is gone . I think the the 6.8 for my use is better than the 6.5 Grendel I have a fair amount of supplies for the 6.8 so I’m ok for a while but if I was buying one now it would probably be the 6.5

[Maxx]

If you could only pick one caliber for general purpose in the criteria mentioned, seems to me .308 is the obvious answer. Reaches out quite a ways, drops medium game animals, and is easy to find.

[MarkCO]

Originally Posted by Maxx

If you could only pick one caliber for general purpose in the criteria mentioned, seems to me .308 is the obvious answer. Reaches out quite a ways, drops medium game animals, and is easy to find.

But not available in an AR15, which the OP specified in the "criteria".

[603Country]

I’m not sure what you guys mean about general purpose and the 223. It really isn’t great for pig hunting, which is why I have a Grendel now.

[rickyrick]

For pigs, it depends on the range. I took 100s of pigs with .223. However, all of them were less than 100 yards and most within 50 yards. I’m not contradicting what 603country is saying either.
That being said I have different calibers for pigs now.
This is a tricky topic, but I still say that the best “all around” caliber AR is the .223/5.56.

Now if I wanted to nit-pick, then the chart posted in reply #9 shows that 6.8spc holds a slight edge over 6.5 Grendel. I have no way of knowing whether that information is accurate or not. However, im not finding a lot of 6.8spc factory ammunition as of late.
I think it depends on how the user wants to budget ammunition expenses In money or time.
My interpretation is that the OP is planning to through a significant number of rounds down range in practice and recreation.

[tangolima]

It is AR. The upper can be swapped very easily. I wouldn't confine myself to only one caliber. A combination of 2-3 complete uppers with associated magazines is what I would have.

But if I absolutely can have only one, I still pick .223 Wylde with 1:7 or 1:8 twist. I can handload with heavier bullets if I need expanded capabilities.

-TL

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[Pistoler0]

Originally Posted by Buckeye!

6.5 Grendel is just a great round.. if u are a handloader … ammo just to expensive
Im a 7.62x39 .. has limitations.. as long as you know’em .. ur good to go

yeah, I roll 7.62x39 with AR too, but not good for big game beyond 150-160 yards (falls below 1000 ft-lbs at that distance). But still nothing cheaper for factory ammo ($0.36 / round)

At $0.79/round for cheapest factory offering, 6.5 Grendel not outrageous.

[Prices per Ammoseek 7/8/2023 ]