Thinking about an AR 6.8 SPC or 300 AAC upper...
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rjrivero
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Looking at it from a simplicity point of view, the 300 Blackout is my option. It uses the same bolt and same magazines as the standard 5.56. The 300 Blackout with 123gr bullets performs on par as the 6.8 as well.
If you're going with the BLK, then the carbine length gas system is as long as you want to go if you're going 16" on the barrel length. If you're going shorter, then a pistol length gas tube is what you want. The pressures are significantly lower than the 5.56. (300 Whisper guys are running mostly pistol length gas tubes for the sake of using hand loads.)
Personally, I have a 16" blackout with a pistol length gas system. I had the 300/221 Fireball reamed out for the 300 Blackout. I can tweak my own handloads to do whatever I want to with that barrel/gas system setup. (I'm running 180gr Subsonic with this setup and having a lot of fun with it.)
If you're going with the BLK, then the carbine length gas system is as long as you want to go if you're going 16" on the barrel length. If you're going shorter, then a pistol length gas tube is what you want. The pressures are significantly lower than the 5.56. (300 Whisper guys are running mostly pistol length gas tubes for the sake of using hand loads.)
Personally, I have a 16" blackout with a pistol length gas system. I had the 300/221 Fireball reamed out for the 300 Blackout. I can tweak my own handloads to do whatever I want to with that barrel/gas system setup. (I'm running 180gr Subsonic with this setup and having a lot of fun with it.)
If you want the fluting, AR Performance and Black Hole Weaponry come to mind for good 6.8 barrels with flute options. I think they are both doing .300 BO too now.
What is the gun going to be used for? For hunting I would say 6.8, but if you like shooting suppressed I would lean for the BO. Either is capable though.
I find the need for a 6.8 specific bolt a non-issue as I prefer to have a matching headspaced bolt for any new barrel anyway. Magazines; those could be an issue if you have a bunch of 5.56 mags and don't want to have another one too.
What is the gun going to be used for? For hunting I would say 6.8, but if you like shooting suppressed I would lean for the BO. Either is capable though.
I find the need for a 6.8 specific bolt a non-issue as I prefer to have a matching headspaced bolt for any new barrel anyway. Magazines; those could be an issue if you have a bunch of 5.56 mags and don't want to have another one too.
Sorry, should have explained the purpose (which pretty much boils down to fun).
Was wanting an AR platform for hunting deer and varmint, plus longer range accuracy for recreational target shooting. I'm interested in a fluted barrel (triangular would be nice but beyond expectation in an AR) for weight/balance, faster cooling, and stability (and I must confess polished SS because my favorite scope is silver
), light free floating hand guard for accuracy comfort and weight, and 18-20 inch barrel for more power less drop at long range (I know it conflicts with AR for hunting but I already have a 7mm mag).
Started thinking of 6.8 spc and got diverted with the 300 aac. Don't care about sub-sonic and silencer but blackout looks pretty good for performance (and it will impress the guys at the range ). Also, I reload so the 300 blackout gives me a better excuse for reloading than the 5.56, which is so darn cheap. Yes, I am very shallow .
I don't know how much of the above is just plain stupid and I am quite receptive to being set straight (other than the silver scope thingie).
That Noveske Rogue Hunter sure does look tempting.
Was wanting an AR platform for hunting deer and varmint, plus longer range accuracy for recreational target shooting. I'm interested in a fluted barrel (triangular would be nice but beyond expectation in an AR) for weight/balance, faster cooling, and stability (and I must confess polished SS because my favorite scope is silver
), light free floating hand guard for accuracy comfort and weight, and 18-20 inch barrel for more power less drop at long range (I know it conflicts with AR for hunting but I already have a 7mm mag).Started thinking of 6.8 spc and got diverted with the 300 aac. Don't care about sub-sonic and silencer but blackout looks pretty good for performance (and it will impress the guys at the range
). Also, I reload so the 300 blackout gives me a better excuse for reloading than the 5.56, which is so darn cheap. Yes, I am very shallow .I don't know how much of the above is just plain stupid and I am quite receptive to being set straight (other than the silver scope thingie).
That Noveske Rogue Hunter sure does look tempting.
The 16" midlength gas 6.8SPC is about ten years further down the road in development and industry acceptance.
The .300 BLK offers simplicity, and about all you need is a barrel. Mags are still up in the air. It's much newer, and not a lot is known about it, but then again, it's a necked out 5.56. It's actually been around since the '70s, shooters were using it then trying to break into competitions where 5.56 was flat banned by the battle rifle crowd. Times change, not too many are using full power .30 cals any more.
In terms of availability, 6.8SPC is well supported, and lots make uppers and ammo for it. Academy even stocks Remington green box, which isn't a bad round. .300 BLK is just starting out, not many offer the few parts needed. Doesn't make it bad, just a longer wait.
Ballistically, good luck getting third party reports comparing them. It's going to be apples and oranges, is it fair to compare SSA's tac loads, or handloads, against whatever is on the market for the .300 BLK when it's still not fully supported?
For medium game, either will likely do the job. Varmints, a 5.56 is more optimum, on the range blasting dirt, 5.56 is potentially a lot cheaper. I don't think 6.8 or .300 will be economically feasible dumping mags on paper. If either caliber is wanted, sorting out what the gun will actually be used for 85% of the time needs to be pinned down first. Then choose the best caliber for that.
The .300 BLK offers simplicity, and about all you need is a barrel. Mags are still up in the air. It's much newer, and not a lot is known about it, but then again, it's a necked out 5.56. It's actually been around since the '70s, shooters were using it then trying to break into competitions where 5.56 was flat banned by the battle rifle crowd. Times change, not too many are using full power .30 cals any more.
In terms of availability, 6.8SPC is well supported, and lots make uppers and ammo for it. Academy even stocks Remington green box, which isn't a bad round. .300 BLK is just starting out, not many offer the few parts needed. Doesn't make it bad, just a longer wait.
Ballistically, good luck getting third party reports comparing them. It's going to be apples and oranges, is it fair to compare SSA's tac loads, or handloads, against whatever is on the market for the .300 BLK when it's still not fully supported?
For medium game, either will likely do the job. Varmints, a 5.56 is more optimum, on the range blasting dirt, 5.56 is potentially a lot cheaper. I don't think 6.8 or .300 will be economically feasible dumping mags on paper. If either caliber is wanted, sorting out what the gun will actually be used for 85% of the time needs to be pinned down first. Then choose the best caliber for that.
SentinelStrategic
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The .300AAC is a good cartridge, but it's a "logistically prohibitive" cartridge. The only ammunition that has managed to make its way onto the market thus far is the 220gr OTM subsonic from Remington. AAC has stated that they have several companies aside from Remington that are on board and in the process of developing commercial ammunition to put out. While it was not said directly whom, it is believed to be Hornady, Federal and I think Black Hills, and likely some more will bloom. However, we won't be seeing any ammunition regularly on the market for at least another 6 months, I suspect. Most people are reloading it right now. If you can get the brass, you can do well with the cartridge. However, until there is more ammunition on the market, you're going to be very limited on what you can do.
The 6.8SPC has a number of load options on the market. Mechanically, I think the .300AAC is the better option due to the similarity of all parts, save the barrel. The 6.8SPC will be the better option for the average shooter in the immediate term, however. If projections are right, the .300AAC will surpass the 6.8SPC quickly in terms of availability and load options, as well as in popularity. However, that's at least a year out, at least from my point of view and opinion. If you want something you can shoot right now without issues, the 6.8SPC is the better option. If you want a longer shot, neither cartridge is especially suited to the task. They are short and intermediate range cartridges. You're not going to get 900m capability like you would from say Mk262.Mod1 loads, or 1000+m capability from M118LR.
Both are capable cartridges, but the .300AAC will be more utilitarian due to a wider array of loading capabilities due to using a .308" bullet.
I have a .300AAC SBR in the works, but it's basically just waiting to be registered and then the receiver will sit in the safe for the foreseeable future until more commercial ammunition hits the market. I can reload the ammo, but lack of available ammunition commercially makes it less than feasible for my purposes.
Just something to think about.
The 6.8SPC has a number of load options on the market. Mechanically, I think the .300AAC is the better option due to the similarity of all parts, save the barrel. The 6.8SPC will be the better option for the average shooter in the immediate term, however. If projections are right, the .300AAC will surpass the 6.8SPC quickly in terms of availability and load options, as well as in popularity. However, that's at least a year out, at least from my point of view and opinion. If you want something you can shoot right now without issues, the 6.8SPC is the better option. If you want a longer shot, neither cartridge is especially suited to the task. They are short and intermediate range cartridges. You're not going to get 900m capability like you would from say Mk262.Mod1 loads, or 1000+m capability from M118LR.
Both are capable cartridges, but the .300AAC will be more utilitarian due to a wider array of loading capabilities due to using a .308" bullet.
I have a .300AAC SBR in the works, but it's basically just waiting to be registered and then the receiver will sit in the safe for the foreseeable future until more commercial ammunition hits the market. I can reload the ammo, but lack of available ammunition commercially makes it less than feasible for my purposes.
Just something to think about.
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Long range accuracy isn't quite right, I'm talking about just 300 yards. Of a bit more concern is maintaining power at longer range with a heavier bullet and a rifle vs the carbine (18-20" barrel), not to mention more bullet stability and consistency against wind and such. As far as ammo is concerned all I need is some brass and loading data (the latter most likely to be a bit scarce for a while I would guess). As far as time is concerned, that's not an issue. I'm in no hurry. I have a safe full of paper punches to keep me occupied.
rjrivero
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SentinelStrategic said:
If you already reload, then making brass from ubiquitous .223 or 5.56 brass is a pretty simple process. I haven't bought ANY rounds for my 300 BLK, nor do I intend to. I do have buckets of .223. It's a simple deal of cutting the case at the neck, sizing, trimming and loading. As you've said, the 300 BLACKOUT will probably surpass the 6.8, in time, and right now, it's a reloaders dream.
I will tell you that the 180gr Nosler soft point is pretty damn accurate at 100 yards pushed with 10.2 gr of A1680. (I'm working on making an affordable 180gr subsonic.
)68wj is absolutely right, in that both of these rounds have little benefit in rifles over 16".
rjrivero
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awgrizzly said:
My first couple hundred, I used a dremel with a cut off wheel. Talk about teadious.
You can neck it down first, then trim, but that's a LOT of trimming.
I use this, now. Best $25.00 I've spent all year!!
http://www.harborfreight.com/power-tools/cutoff-saws/bench-top-cut-off-saw-42307.html
New 6.8 ammo option. http://shopwilsoncombat.com/68-SPC/products/409/
http://shopwilsoncombat.com/68-SPC/products/409/- Status
