Favorite cartridge for the AR-15, and it's use case.

[Show Me]

Remember the parts kits. And the companies that sold all that cool stuff. The 14 inch barrel with the welded flash hider. Carry handle upper. I got 5.56 because that's all there was. I have the cmmg cmmc what ever, 22lr bolt and magazine. Loading the mag takes a few. When they first came out I got the M&P sport in 5.56 because it's all there was. I'm done buying so I'll just read what you all put out. If I need bigger I have rifles that shoot the other
" military grade ammo" from 1873 and 1906 so I'll be fine.

 

[adcoch1]

What's your purpose for the Grendel?

The only two AR's I have are .300 BLK and 6.5 Grendel. I couldn't say which is my favorite, they have very different focuses. I built the 16" Blackout for CQB and it's a great round out to about 200 yards. I built my 20" Grendel for long range, and it works to a little past 1000 yards. The two uppers share a common lower.

I have two Grendel's at the moment, one is a 16" upper as a host for a night vision scope, hopefully for hunting someday, and the other is a 20" with an lpvo on it for anything a rifle is for. I hope to hunt antelope with it someday. I really think the Grendel may be the best of the AR cartridges, but the little blackout won top listing for me due to its fun factor, both shooting and at the reloading bench. 5.56 I have just because the Democrats don't like them, and for occasional varmints.

 

[lightman]

My choice would be and is 5.56/223. Possible use is for wild pigs, plinking and possible home defense.

 

[CarJunkieLS1]

If we can talk about Wildcat Cartridges, you favorite has to be the 7mm Valkyrie AR. Deer hunting is it's only use a 2780fps 20" barrel 120 Nosler BT makes a quick work of deer size game.

If it's SAAMI approved cartridges I gotta go with my 300 HAMR. Use would be deer and this year I plan to set it up for nighttime coyote/hog hunting.

 

[Varminterror]

When they first came out I got the M&P sport in 5.56 because it's all there was.

What do you mean by this? I'm not sure I get it.

 

[Show Me]

Had no other choice.

 

[Varminterror]

This thread has been a head scratcher for me, largely because I hold an internal conflict between thoroughly enjoying the process of designing and building purpose built rifles for specific use cases, BUT also thoroughly enjoy redeploying rifles and cartridges across multiple use cases, which may not particularly well match their design intents.

So within the folds of my personal subjective analysis, the 6mmAR/243LBC has likely been my favorite AR-15 cartridge I've ever used (and I've built AR's in DOZENS of cartridges). It's a little easier to load than 6 ARC with a more forgiving powder, a little better for a little longer range shooting than 6.5 Grendel with a little better impact splash than 224 Valk or 22 Nosler, cheap to shoot, easy to build, has brass available without specialized case forming to make it, it behaves well in 10" barrels through 26" barrels, great for deer and hogs, great for pdogs... It's an incredibly versatile little cartridge.

 

[jmr40]

223/5.56 with bullets from 50-75 gr does everything I need an AR-15 to do. I have complete faith it will work on deer size game and on targets to at least 600 yards. The 6.5 and 6.8 cartridges are tempting, but I still wouldn't hunt anything larger than deer with anything else you can put in the AR-15 platform.

If 223/5.56 isn't enough I'd move to the AR-10 rifle to get a cartridge with enough more power to matter.

 

[Show Me]

Can't help with your head conflict but I hate 6mm arc. Got a TC. Barrel to see what the big deal is. Almost as aggravating as the 30 AR was. You know the one with the power of a .308 in your AR. Glad Remington got sucked dry

 

[Show Me]

Looked up your LBC. Not much to read

 

[mcb]

Can't help with your head conflict but I hate 6mm arc. Got a TC. Barrel to see what the big deal is. Almost as aggravating as the 30 AR was. You know the one with the power of a .308 in your AR. Glad Remington got sucked dry

Lol, I love my 30 RAR.

 

[BreechFace]

Lol, I love my 30 RAR.

I know, it's too bad Remington sucks at marketing new cartridges. It's plagued them for a long time.

I always thought the 30 Rem AR offered great hunting potential in an AR15. I moved onto the 450 Bushmaster and 358 Yeti, but was once really interested in finding a barrel, bolt and a bunch of ammo; but that ship has sailed.

 

[Varminterror]

Looked up your LBC. Not much to read

The 6mm AR/6 Grendel/243 LBC are a straight neck down of the 6.5 Grendel case. No fireforming, no case cutting, no reaming, just run factory 6.5 Grendel brass into a 6mm AR/243 LBC die (I even do mine in a 6.5 Grendel Redding Type S Bushing die with a .269" bushing). Spill as much 8208 into the case as can fit under a 105 Hybrid and Bob's your uncle, life is good.

These have been around a long time, naturally, since the PPC predates both Whitley's 6mmAR and Les's LBC, and since neither were the first to neck down a 6.5 Grendel to 6mm (knowing someone DID about 5min after the brass hit the shelves). The extra ~1.5grn powder capacity of the straight Grendel case allows about 100fps more, and gives just enough expansion ratio advantage to allow 8208 to do what it does, with better stability than LR in the ARC case. I bought my first barrels about 2 years before the ARC launched, after wasting a couple of years wringing my hands over the decision between a Turbo40 and a FatRat (both improved versions of the same case), but I'm glad I finally bit the bullet and got into a 6 Grendel variant when I did.

 

[mcb]

I know, it's too bad Remington sucks at marketing new cartridges. It's plagued them for a long time.

I always thought the 30 Rem AR offered great hunting potential in an AR15. I moved onto the 450 Bushmaster and 358 Yeti, but was once really interested in finding a barrel, bolt and a bunch of ammo; but that ship has sailed.

It was quite the proprietary upper but the cartridge itself is not to bad. I have done allot of hunting with mine the past few years. I lucked into an upper, some spare parts, and a life time supply of brass. I even lucked into a set of RCBS reloading dies at the local pawn shop. The real find was a guy selling two mystery magazines on AR-15.com that I recognized as the very hard to find 10rd magazines.

 

[CarJunkieLS1]

Lol, I love my 30 RAR.

I love my 30 Rem AR also. 125 Accubond reloads are Thors Hammer on deer and coyotes.

BTW super jealous of the 10 round mags you have. I've never seen one for sale. A friend of mine has one for his rifle.

Years ago I lucked up and found a supply online of the 4 round 30 Rem AR mags, I got a few extra and my friend got a few too. Of course they are ghosts now.

 

[Anchorite]

This thread has been a head scratcher for me, largely because I hold an internal conflict between thoroughly enjoying the process of designing and building purpose built rifles for specific use cases, BUT also thoroughly enjoy redeploying rifles and cartridges across multiple use cases, which may not particularly well match their design intents.

On the AR platform? Do you stick that platform or do you do bolt actions too?

 

[InTheSwamp]

223/5.56, but I have the itch for the 6 ARC and 22 ARC.

 

[NIGHTLORD40K]

5.56 for the same reason Uncle Sugar likes it.

 

[mcb]

I love my 30 Rem AR also. 125 Accubond reloads are Thors Hammer on deer and coyotes.

BTW super jealous of the 10 round mags you have. I've never seen one for sale. A friend of mine has one for his rifle.

Years ago I lucked up and found a supply online of the 4 round 30 Rem AR mags, I got a few extra and my friend got a few too. Of course they are ghosts now.

He didn't know what he had until I told him. He was then kind enough to sell them to me for what he had in them.

It's not a 10rd magazine but you can take some of the old Bushmaster straight body 450 Bushmaster magazines and modify the follower (Sometimes you need to also shorten or adjust the feed lips slightly) and make it into a pretty reliable 7rd 30 RAR magazine.

 

[Varminterror]

On the AR platform? Do you stick that platform or do you do bolt actions too?

AR’s, bolt guns, leverguns, revolvers, pistols… Used to have a bunch of break action pistols and rifles too, pump guns and other semiauto actions too… picking parts to achieve the objectives dictated by the task is what intrigues me.

We can do a lot with the AR design, even do a lot with the AR-15 design.

 

[wesmonster]

I run 5.56, .300 bo, 7.62x39, 5.45x39 & 6.5 Grendel.
.300bo is my favorite of the bunch but they all have their strengths.
5.45x39 will probably retire whenever I burn thru all my surplus 7n6.
I have a few AKs and a VZ58 so 7.62x39 will always be stacked in my shop.
6.5 Grendel is a great performer but I don't reload anymore so unless cheap steel case Grendel starts importing again I won't be shooting as much.
5.56 isn't my favorite caliber but I run a BCM 14.5" pinned lightweight middy which is a featherweight and a soft shooter. After shooting my 20" heavy barrel 6.5 Grendel the BCM feels like airsoft.

6.8 spc and .450bm are two calibers I'd like to try one day.

 

[mavracer]

I don't really do favorites, different uses can dictate different preference.
I've got ARs in 22LR, 5.56, 224 Valkyrie, 6mm Creed, 300 Blackout, 308, 350 Legend and 450 Bushmaster and am in the process of putting a truly superfluous 9mm pistol together.
The 22s are a great plinker/trainer guns I have 1 upper that mimics my 300 SBR and 1 that mimics my 16" 5.56 Recce inspired gun.
5.56 are the easy button for most AR uses targets to 600, varmints and light skinned game and about any defensive purpose.
I have 3 the aforementioned Recce, a SBR and a 20" set up as a service match rifle.
I jumped on the 224 bandwagon and got dumped in a rabbit hole, in that process I figured out a lot and am ultimately happy with it now that I have it figured out what it does well and what it doesn't.
Mine is a 20" 7.7 twist would make a fantastic varmint rifle but mine gets used to launch 80gr bullets at mag length for long range as a cheaper lightweight substitute for my 6mm Creed.
The 6mm Creed is a fantastic long range cartridge in an AR10 and does all the hunting duties a 243 can.
300 Blackout is pretty versatile works well suppressed with subs or supers and works really good in SBRs.
308, well a 308 AR10 is hardly ever a wrong answer.
I put my 350 Legend together as a MSR version of the 30/30 lever gun for hunting pigs and the 450 as the 45/70.

 

[small town life]

In the 15 platform I have 5.56 (in nato & wylde chambers), 6.5gren, 6.8spc and 300bo. The 15 platform without the 15 sized magwells are in pic's. I do have a 5.7x28 upper that uses p90 mags and ejects down the 15 magwell. I only shoot paper, steel and piggies.

 

[CarJunkieLS1]

He didn't know what he had until I told him. He was then kind enough to sell them to me for what he had in them.

It's not a 10rd magazine but you can take some of the old Bushmaster straight body 450 Bushmaster magazines and modify the follower (Sometimes you need to also shorten or adjust the feed lips slightly) and make it into a pretty reliable 7rd 30 RAR magazine.

I took my 4 round ones, and ground out the little tabs at the bottom of the mag and you can get another round it, gives me a total of 5. That's all I need really for hunting.