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Puuloa
09-18-2012, 10:42 PM
I am thinking of the next AR build. I can't decide between 5.56 or 6.8 SPC with respect to power, accuracy, cost of build, cost of ammo, reliability and availability of accessories. Any suggestions? I'm leaning towards tacticool.

bluebird
09-18-2012, 10:45 PM
50BMG.

DannyInSoCal
09-18-2012, 10:52 PM
Stick with 5.56 for killing paper -

6.8 is great for hunting boar, big horn sheep, and deer.

It splits the difference between 5.56 and 7.62x51 -

Both in ammo and build cost.

Besides - 30rd 5.56 mags become 26rd 6.8 mags with a simple follower swap...

:43:

MrPlink
09-18-2012, 11:16 PM
300blk

JeremyKX
09-18-2012, 11:17 PM
300blk

+1 :cool:

bluebird
09-18-2012, 11:33 PM
+1 :cool:

-1. I sold my 300BLK upper even before I shot it because ammo was so hard to find back then. I can't imagine someone getting a 300BLK without reloading.

Chameleon Loco
09-18-2012, 11:39 PM
5.56 is alot cheaper to shoot and is fine for varmints and pests, but 6.8 spc is great for hunting medium sized game. The down side is it is alot more expensive than 5.56.

DarkSoul
09-19-2012, 6:17 AM
I also vote for 300 BLK, but agree, unless you are reloading, at times it can be hard to find ammo. The good thing is, is if you do reload, it's very inexpensive for plinking rounds, and the brass is time consuming if you make it yourself, but there are several places now that sell bulk 300BLK brass.

The 6.8 is just expensive, no two ways about that. Good ballistics and stopping power, but your gonna pay for it.

starsnuffer
09-19-2012, 7:27 AM
I am thinking of the next AR build. I can't decide between 5.56 or 6.8 SPC with respect to power, accuracy, cost of build, cost of ammo, reliability and availability of accessories. Any suggestions? I'm leaning towards tacticool.

Given your criteria, but lack of what you actually planning on using it for, I have to assume you'll be shooting this off a bench at no more then 100 yards.

Go with 5.56.

-W

nyc71
09-19-2012, 7:29 AM
If you reload 6.8. The question is how often would you shoot either caliber? A lot of my coworkers have the 5.56 but don't take the time to train with it. Most people have the "desire" to shoot but don't create time for it. I have booth caliber but my 5.45 AR gets most of the trigger time.

Drivedabizness
09-19-2012, 8:07 AM
My 6.8 (when I get it) will primarily be used for hunting. Minimal ammo expense as I'll do most of my "training" w/5.56.

gun toting monkeyboy
09-19-2012, 9:41 AM
If you already have a 5.56, go ahead and build one in whatever caliber floats your boat. 6.8 is a good all-around AR caliber. It costs more to shoot, but it is also a lot more useful on game and such. With 6.5 and .300 blackout both becoming more common, you might also look into those. I'll stick with the 6.8 myself.

-Mb

helpme
09-19-2012, 9:47 AM
I am thinking of the next AR build. I can't decide between 5.56 or 6.8 SPC with respect to power, accuracy, cost of build, cost of ammo, reliability and availability of accessories. Any suggestions? I'm leaning towards tacticool.

Have you looked at 6.8 ammo prices:TFH:? They're a bit higher than 5.56...

5.56 is also an extremely accurate round out to 300 or so meters, and can get solid silhouette sized hits out to past 600 yards. All depends on the parts/ammo quality.

For your purposes, I'd say go 5.56 for now.


(I have a 5.56 & 6.8 setup so I speak from experience)

Knight_Who_Says_Ni
09-19-2012, 9:48 AM
.300 BLK for sure. Ammo is getting to be really easy to find, all the local gun stores carry it up here.

starsnuffer
09-19-2012, 10:31 AM
.300 BLK is a PDW caliber primarily to replace .45 in surpressed SBR's. It can be loaded supersonic to be effective at longer ranges allowing the use of a single carbine to handle PDW and common battle engagement distances. However, it is about as effective (as opposed to more effective) as 5.56 out to 200 yds. Beyond this 5.56 is actually more effective.

Be careful recommending this cartridge without knowing the intended purpose. It is more expensive then 5.56, so let your needs dictate what you buy, unless you just want it cos it's tacticool.


-W

wash
09-19-2012, 1:19 PM
5.56 mags are not 6.8 SPC compatible. You will need different mags but mags are pretty cheap.

6.8 SPC is a great 300 yard hunting round when loaded properly and paper accurate out well past 500 yards.

5.56 was designed to wound more than to kill so unless you buy hunting ammo that is nearly as expensive as 6.8 SPC hunting ammo, it's more of a varmint, self defense, plinking and paper punching rifle.

.300 AAC Blackout probably kills effectively with the right bullet but the killing range is going to be shorter than 6.8 and the expensive bullet kind of kills the whole inexpensive reloading deal.

So figure out how much money you want to spend on ammo and the type of shooting you want to do before you choose.

TwinStick
09-19-2012, 1:27 PM
5.56 mags are not 6.8 SPC compatible. You will need different mags but mags are pretty cheap...

Are you sure about this? I've heard the contrary multiple times, but I don't know from personal experience.

After doing some searches, it looks like maybe some 5.56 mags work for 6.8 and some don't

rusty815
09-19-2012, 1:30 PM
With a proper load, a 6.8 can have an effective expansion and killing range of about 450 yards.

imo, the 300BLK is only usefull in a suppressed SBR, but since we can't run suppressors in Kommiefornia, then the 300BLK looses its appeal.

You could also look into the 6.5G, which is very close to the 6.8 in performance. Brass for the 6.5 is a little hard to find but it has a better bullet selection imo.

rusty815
09-19-2012, 1:31 PM
Are you sure about this? I've heard the contrary multiple times, but I don't know from personal experience.

Technically they're not, but you can swap the follower in a 5.56 mag with a 6.8 follower and it will work just fine.

TF_CAM
09-19-2012, 2:17 PM
swap the follower on the mags, and bend the lip out a little on the top of the mag and you wont have a problem.. but once you bend the mag to convert it from 5.56 to 6.8 dont bend it back, just get new mags..

wash
09-19-2012, 4:05 PM
The difference between 5.56 magazines and 6.8 SPC magazines is that the ribs on the side of the magazine are shallower which allows the wider case to properly doublestack.

It's different enough that Magpul has said they would never make 6.8 SPC Pmags because it would make the magazine walls too thin.

When you take a 5.56 magazine, swap the follower and load it with 6.8 SPC ammo, the rounds don't stack vertically so the spring force works to bulge the magazine instead of feed the rounds.

It might work, it might hang up.

If you get real 6.8 magazines, the rounds stack and there is far less bulging force and I've never had a problem with them.

Uriah02
09-19-2012, 4:13 PM
Given your criteria, but lack of what you actually planning on using it for, I have to assume you'll be shooting this off a bench at no more then 100 yards.

Go with 5.56.

-W

+1
If you don't reload, the price difference for shooting paper is not worth it at all.

tacticalcity
09-19-2012, 4:19 PM
+1
If you don't reload, the price difference for shooting paper is not worth it at all.

I agree with this. I am not against owning a 6.8SPC AR, if it is in addition to and not in place of a 5.56mm AR. Just like I am not against owning a .308 AR just so long as you also have a 5.56mm AR. The rounds all have their areas where they shine. More often than not, however 5.56mm will be the round you will shoot. When you factor in price, distances of most ranges, and other practical issues it is a smarter bet.

Gromit
09-19-2012, 8:18 PM
Anyone feel like 6.8 is harder to find in stores than 5.56?

I can find 5.56 in a Walmart, but I have to really search around to find a store that carries 6.8. Is it just the area where I live?

rusty815
09-19-2012, 8:52 PM
Anyone feel like 6.8 is harder to find in stores than 5.56?

I can find 5.56 in a Walmart, but I have to really search around to find a store that carries 6.8. Is it just the area where I live?

Of course its harder, 5.56 is arguably the most common caliber out there, it's pretty much impossible to find a place that sells ammo that doesn't have 5.56.

There are a few stores that I frequent in Westminster and San Diego that has 6.8 ammunition, with pretty decent prices too.

Puuloa
09-19-2012, 9:01 PM
Thanks for the comments guys. I'm gleaning the bits of knowledge from all your posts. I already have 3 ARs at 5.56 so I think 6.8 it is. It would be used for zombies. lol.

fourtraxmc
09-20-2012, 10:29 AM
Rumor has it that Federal and Tula will be making ammo early 2013. Should help cost of practice or plinking.

killathrilla
09-20-2012, 10:31 AM
...

starsnuffer
09-20-2012, 10:48 AM
Tula already makes 6.5G ammo.

6.5 G is the superior cartridge beyond 400M. Under 400m 6.8 and 6.5 behave about the same. Muzzle velocity and energy is higher across the board for 6.5.

-W

ExtremeX
09-20-2012, 11:05 AM
I would take AR uppers in these calibers in this order. This is based on my own research, preferences and findings. This takes into account the fact that I reload, and applications for longer range target shooting which is my primary interest.

5.56, which you already have.
6.5 Grendel
.243 WSSM
6.8 SPC

For some reason a lot of people love the .300BLK but most of its advantages can’t be had in CA as rusty815 pointed out... If I could run a suppressor and or have an SBR I would be all over it. It’s a trendy caliber most people in CA.

It all comes down to application and picking a cartridge that excels in that area.

If you hunt the 6.8 would probably be on top of that list for me.

wash
09-20-2012, 11:17 AM
Tula already makes 6.5G ammo.

6.5 G is the superior cartridge beyond 400M. Under 400m 6.8 and 6.5 behave about the same. Muzzle velocity and energy is higher across the board for 6.5.

-W
Not true, 6.8 has a clear muzzle velocity and energy advantage up close.

It's only at very long range that Grendle catches up and at that point they are both getting marginal for bullet expansion.

I prefer 6.8 because at the range I'm likely to take a shot, it's as good or better and the magazines are much better.

edgerly779
09-20-2012, 12:01 PM
I shoot and handload both, For just plinking .223 . people keep posting 5.56 but almost no one shoots it. For more punch and hunting i use my 6.8. Load from 85 gr non lead to 110 gr
jacketed lead. Tending more toward my 6.8 bullets almost 1 1/2 times as much. Powder only 4 more grains. Same primer cost. Brass 1 1/2 times the cost. Only for first round then once you own them no difference.

peter95
09-20-2012, 9:23 PM
If you're looking to be hunting with it, go 6.8, but for paper punching, stick with 5.56/.223