6.8mm anyone?
- Thread starter RSK
- Start date
Yep.. 5.56 is a lot cheaper and it makes the paper just as dead
I have an XCR-L and a Ruger Hawkeye Compact in 6.8 SPC, both non-restricted. It's not that popular because there is so much cheap surplus 5.56 and 7.62x39 around and no 6.8 surplus. Check out 68forums.com for tons of information on all things 6.8, great bunch of guys on there too.
Exactly.. I can get .223 ammo that will go bang cheaper than I can buy the reloading components and that doesn't even account for my time. I shoot it out of a 2MOA rifle so it's not like I need to feed a tackdriver.
I have a non restricted length 6.8 SPC barrel for my ACR, just waiting for my bolt to show up to complete the package. From what I've read it launches a 110-115 grain bullet around 2400-2600 fps which is decent and should make a nice deer round for under 200yd shots. I'm excited to give it a try but I haven't decided yet if I'll keep it once I get my 300 Blackout barrel built.
Cool story bro, but the 6.8 SPC is a great caliber that really shines in black rifle hunting applications, particularly in provinces where we have caliber restrictions.
Also it is better at longer ranges than 5.56, so if you shoot past 300m you will see some benefit in 6.8 as it has less drop than 5.56 and is not affected by wind as much. Also if you don't shoot for accuracy it doesn't mean that others don't.
I'm not saying it's a bad caliber. Actually, I WISH it was used by our armed forces both for their benefit and for my benefit of it making it out to the surplus market. I absolutely agree with EVERYTHING you said. I was just explaining why 5.56 is more readily available on our market.
Two 5 shot groups @ 100 yards from my 6.8 SPC AR build. This is a great cartridge. I also have a Ruger Mini in 6.8 which makes a great deer/coyote rifle. This cartridge has a lot going for it in terms of accuracy and lethality on game. Not for everyone, though.
What bullets and powder do you use?
I'm just getting geared up to load for it and picked up some H322 as I've read it's the best powder for the cartridge.
I also picked up 300 Remington 115gr FMJ but will need something that expands when I use it hunting in my non restricted ACR with Questar stainless match barrel. I'm expecting some nice groups once I do some load development
Those are outside to outside measurements, go center to center and they are much more impressive
What bullets and powder do you use?
I'm just getting geared up to load for it and picked up some H322 as I've read it's the best powder for the cartridge.
I also picked up 300 Remington 115gr FMJ but will need something that expands when I use it hunting in my non restricted ACR with Questar stainless match barrel. I'm expecting some nice groups once I do some load development
Those are outside to outside measurements, go center to center and they are much more impressive
Speer 90 gr. HP's give the most consistent accuracy. The Remington fmj gave very poor accuracy in my AR. YMMV. H322 is a very stable powder, and, yes, gives good accuracy. The most recommended powder is 10X.
BTW, some case necks are very thin and some bullets may not seat securely. If you don't feel the expander button expanding the neck- check that the bullet isn't loose after you seat it. You will come across this on 6.8 Forums.
If it's under an inch outside to outside with a 5 shot group, I can't be bothered to subtract the diameter.
It's working!Speer 90 gr. HP's give the most consistent accuracy. The Remington fmj gave very poor accuracy in my AR. YMMV. H322 is a very stable powder, and, yes, gives good accuracy. The most recommended powder is 10X.
BTW, some case necks are very thin and some bullets may not seat securely. If you don't feel the expander button expanding the neck- check that the bullet isn't loose after you seat it. You will come across this on 6.8 Forums.
If it's under an inch outside to outside with a 5 shot group, I can't be bothered to subtract the diameter.
Thanks for the pointers, I just bought the 115gr Rem bullets because they were cheap and it will get me playing. I bought 100 new Hornady cases to get started with. I'll try the Speer 90gr and use them on deer next fall once I have a load developed. If you can get 2900fps from the 6.8 I may be keeping it after all, that will be plenty of zip for hunting.
Those are some sweet groups, were those with the Speer 90gr?
Why do you have your scope jacked up so high?
Hornady cases usually don't have the neck issues. Good choice. Yes, Speer 90 gr. HP. VMax bullets work well also but not good for deer. TTX should do the job on deer.
Regarding the scope: I have huge cheekbones. Seriously, that riser was all I had when I first got it. Had waited almost 2 years for some of the parts. Just wanted to shoot it so went with what I had. It now has an American Defense QD mount. Much better.
BTW, Nosler makes a 115 gr. competition bullet in 6.8. Have had some success with them but need more load development.
Hornady cases usually don't have the neck issues. Good choice. Yes, Speer 90 gr. HP. VMax bullets work well also but not good for deer. TTX should do the job on deer.
Regarding the scope: I have huge cheekbones. Seriously, that riser was all I had when I first got it. Had waited almost 2 years for some of the parts. Just wanted to shoot it so went with what I had. It now has an American Defense QD mount. Much better.
BTW, Nosler makes a 115 gr. competition bullet in 6.8. Have had some success with them but need more load development.
I'll be running the cheapest bullets I can as long as I can find something that gives decent accuracy and saving the expensive bullets for hunting only once load development it done.
I bought the Hornady brass because that is what was in stock when I went in. Guess I got lucky
Here is my ACR with the 6.8 barrel in it. Also has Geissele super ACR trigger.
- Location
- Vernon, BC
Gentlemen
If I may chime in and share some thoughts in as well.
I think the 6.8 SPC is one of the most under rated cartridges out there.
What's not to like.
Has 80% the power of a similar length barreled 308 (Until about 300 yards or so), only 20% more recoil than the 223 (5.56 Nato), and fits in an AR-15 foot print.
I have done several builds, all of which have been on the AR platform. My favorite barrel length is 16", however this may vary with purpose. If you can get you hands on it, Stag makes a great 6.8,
Here are a few samples:
Stag 16" 6.8 spc in OD green with Vltor Carbine stock (build was not quite done at this point)
Stag 16" in 6.8 SPC in Flat dark earth with UBR:
Stag 16" in Black with CTR:
I believe this was a DPMS 20" Heavy barreled build on a Stag lower. I had ATRS specially bore out one of their Spartan breaks for this one.
This was one of may favorite builds. This was a combo build. One lower with a 16" HB upper in 5.56 Nato and another upper in 6.8 SPC with a 16" M4 Style barrel. This was one that I had wished I kept
There are others, but this will give you and idea of what is possible.
regards and all the best
AbH
If I may chime in and share some thoughts in as well.
I think the 6.8 SPC is one of the most under rated cartridges out there.
What's not to like.
Has 80% the power of a similar length barreled 308 (Until about 300 yards or so), only 20% more recoil than the 223 (5.56 Nato), and fits in an AR-15 foot print.
I have done several builds, all of which have been on the AR platform. My favorite barrel length is 16", however this may vary with purpose. If you can get you hands on it, Stag makes a great 6.8,
Here are a few samples:
Stag 16" 6.8 spc in OD green with Vltor Carbine stock (build was not quite done at this point)
Stag 16" in 6.8 SPC in Flat dark earth with UBR:
Stag 16" in Black with CTR:
I believe this was a DPMS 20" Heavy barreled build on a Stag lower. I had ATRS specially bore out one of their Spartan breaks for this one.
This was one of may favorite builds. This was a combo build. One lower with a 16" HB upper in 5.56 Nato and another upper in 6.8 SPC with a 16" M4 Style barrel. This was one that I had wished I kept
There are others, but this will give you and idea of what is possible.
regards and all the best
AbH
Last edited:
- Location
- Vernon, BC
Gents
On more thought before the Nay sayers jump in there are some points I want to clarify
I have worked with both calibers (6.8 spc AND 308/7.62 Nato) in a 16" AR carbine configuration, and it has been my experience, that for the 16" carbine configuration, the 80% rule of thumb holds true, but allow me to qualify that statement.
You will never reach that 80% power thresh hold with factory loads. Factory loads are very mild, and are taking in to consideration that there are many Sami spec chambers out there with a 1-10 twist (ala RRA & YHM). It has been found that this barrel configuration, while reliable and hard hitting, causes increased pressure prematurely, or moves the pressure curve forward, and is not optimal for ballistic performance in an AR.
What has been found to work well is the SPC II chamber configuration, with a 1-11 twist. This elongates the pressure curve and allows excellent performance in the 90-115 grain range (with 110 grain bullets being optimal) with out battering the action components and allowing for very good carbine longevity. Those manufactures who are serious about this caliber have gone to that configuration.
I will grant you, there is no real replacement for 7.62 NATO, and it is really one of my favorite caliber in an AR configuration. Lets Face it, the 7.62 NATO has been turning cover into concealment long before the 6.8 SPC was a gleam in its creators eye.
However where space, weight, muscle memory, ammo payload, and penetration are chief considerations, it is very difficult to beat the 6.8 SPC in an AR package.
Again I am just a lay person, and there are just my thoughts. However if I could only have one black rifle, it would be in 6.8 SPC
Regards and all the best
AbH
On more thought before the Nay sayers jump in there are some points I want to clarify
I have worked with both calibers (6.8 spc AND 308/7.62 Nato) in a 16" AR carbine configuration, and it has been my experience, that for the 16" carbine configuration, the 80% rule of thumb holds true, but allow me to qualify that statement.
You will never reach that 80% power thresh hold with factory loads. Factory loads are very mild, and are taking in to consideration that there are many Sami spec chambers out there with a 1-10 twist (ala RRA & YHM). It has been found that this barrel configuration, while reliable and hard hitting, causes increased pressure prematurely, or moves the pressure curve forward, and is not optimal for ballistic performance in an AR.
What has been found to work well is the SPC II chamber configuration, with a 1-11 twist. This elongates the pressure curve and allows excellent performance in the 90-115 grain range (with 110 grain bullets being optimal) with out battering the action components and allowing for very good carbine longevity. Those manufactures who are serious about this caliber have gone to that configuration.
I will grant you, there is no real replacement for 7.62 NATO, and it is really one of my favorite caliber in an AR configuration. Lets Face it, the 7.62 NATO has been turning cover into concealment long before the 6.8 SPC was a gleam in its creators eye.
However where space, weight, muscle memory, ammo payload, and penetration are chief considerations, it is very difficult to beat the 6.8 SPC in an AR package.
Again I am just a lay person, and there are just my thoughts. However if I could only have one black rifle, it would be in 6.8 SPC
Regards and all the best
AbH
Thanks AbH,
My barrel is SPC II 1:11 so that is good new for me. Being that the barrel is non restricted length and that the rifle is in right now being verified to be made non restricted I'm really excited to get out this fall to do some whitetail hunting with it. I rarely need to make a shot beyond 100yds on deer so I think it is going to have more than enough power and it will be a blast ripping around on the quad with my ACR slung over my back.
I'm still trying to decide if I'm going to get the barrel coated black or not. I like the looks of it stainless but also like my non restricted 223 barrel which is black.
This may become my go-to hunting rifle
My barrel is SPC II 1:11 so that is good new for me. Being that the barrel is non restricted length and that the rifle is in right now being verified to be made non restricted I'm really excited to get out this fall to do some whitetail hunting with it. I rarely need to make a shot beyond 100yds on deer so I think it is going to have more than enough power and it will be a blast ripping around on the quad with my ACR slung over my back.
I'm still trying to decide if I'm going to get the barrel coated black or not. I like the looks of it stainless but also like my non restricted 223 barrel which is black.
This may become my go-to hunting rifle
