[Buell056]

So now that I just picked up a stripped Mega upper, I'm gonna build it into a 6.8 SPC upper. I've reviewed the 6.5 as well as 300 blackout options but believe the 6.8 SPC will fulfill my swamp donkey slaying needs as well as others down the road.

Barrels: Have looked at JSE with 1:10 twist and liked what I read. Last build I used a PSA barrel in 5.56 and was satisfied with results but wondered if anyone has used JSE or another brand that worked out well. Looking for carbine length gas system but I guess midlength could work too. Just that midlength gas tubes etc are not as easy to find (I have seen them online but just thinking if I needed to swap parts between rifles might as well keep similar.

BCG: no where to start with this caliber. I have used WMD NiCorr BCGs on .223/5.56 builds and loved them but just looking again for other input.

Im pretty sure can use standard AR mags just need to change out follower for reliability. Any advice on gas blocks? I've used YAnkee Hill before but that's it. Any other input would be great.

 

[JVG]

I have built an AR in both calibers. My 6.8spc is a White Oak Armament (WOA) 16" Match Barrel and my .300BLK is a 16" Rainier Arms Select.
Both guns shoot great. 6.8SPC has more ammo availability. 6.8 requires a separte bolt and magazines (ar mags bind no matter how much time you waste dicking around with them) while the .300BLK requires nothing more than a barrel and utilized all the other standard AR15 parts. I enjoy the 6.8 more

I have and extra 6.8 NiB coated bolt around here in my spare parts bin i believe.

 

[meketrefe]

I have these calibers mentioned here.

The 300 Blackout is great for subsonic / supressed purpose. For supersonic it lacks of powder capacity to achieve any substantial gains.

If supersonic is the desired objective 6.8spc or 6.5LBC are a lot superior whether is hunting, long range, defense, etc... You need the dedicated mags and bolts but most people have a complete dedicated upper for a special purpose anyway. With the blackout you can form brass from .223 Remington brass but it is labor intensive and whether you recycle .223 brass or not prepare to reload any of the options to make the cost more reasonable. All ammo is expensive now.

If you are really concerned about simplicity and cost of brass I would do a 6x45. This will only need a new barrel like the blackout but will also be far superior to the blackout in supersonic mode and easier to reload for too. I mean unless you already have a truck load of light 308 bullets that you want to shoot otherwise the 6mm department is filled with great choices for hunting, target even varmint.

After years of using all those calibers many times I resort to the simple and reliable 6x45 but the power of the 6.8 is amazing for a deer / hog slayer even far out to 300 yards. Something not typical in the northern woods but if you can hit it, it can do the job.

Never get a carbine length system. IMO they should not even exist in the first place. MidLength port is ok. Plenty of dwell time and it is easier on the parts and action.

 

[Buell056]

Appreciate the info ; PM inbound regarding BCG.

I have built an AR in both calibers. My 6.8spc is a White Oak Armament (WOA) 16" Match Barrel and my .300BLK is a 16" Rainier Arms Select.
Both guns shoot great. 6.8SPC has more ammo availability. 6.8 requires a separte bolt and magazines (ar mags bind no matter how much time you waste dicking around with them) while the .300BLK requires nothing more than a barrel and utilized all the other standard AR15 parts. I enjoy the 6.8 more

I have and extra 6.8 NiB coated bolt around here in my spare parts bin i believe.

 

[Buell056]

I hadn't looked yet regarding gas system length however I just seem to have issues getting the right parts for mid length. I've gotten so many carbine length gas tubes by mistake via mail from gun broker etc (literally 3 from diff people). Just figured id look but if it doesn't exist, guess that decision is made. LoL. I agree on the 300 blackout; from ballistic data I've seen on YouTube and online, it lacks the thump 6.8 has. I've never heard of the 6x45 caliber before....

I have these calibers mentioned here.

The 300 Blackout is great for subsonic / supressed purpose. For supersonic it lacks of powder capacity to achieve any substantial gains.

If supersonic is the desired objective 6.8spc or 6.5LBC are a lot superior whether is hunting, long range, defense, etc... You need the dedicated mags and bolts but most people have a complete dedicated upper for a special purpose anyway. With the blackout you can form brass from .223 Remington brass but it is labor intensive and whether you recycle .223 brass or not prepare to reload any of the options to make the cost more reasonable. All ammo is expensive now.

If you are really concerned about simplicity and cost of brass I would do a 6x45. This will only need a new barrel like the blackout but will also be far superior to the blackout in supersonic mode and easier to reload for too. I mean unless you already have a truck load of light 308 bullets that you want to shoot otherwise the 6mm department is filled with great choices for hunting, target even varmint.

After years of using all those calibers many times I resort to the simple and reliable 6x45 but the power of the 6.8 is amazing for a deer / hog slayer even far out to 300 yards. Something not typical in the northern woods but if you can hit it, it can do the job.

Never get a carbine length system. IMO they should not even exist in the first place. MidLength port is ok. Plenty of dwell time and it is easier on the parts and action.

 

[meketrefe]

This I created from a 6x45 AR project...

http://www.nyfirearms.com/forums/ar-15/22960-ar-15-6x45-tactical-lion-round-cat-size-package.html

Also take a look here to see a quick comparative on some alternative calibers using commercial ammunition I tested...

http://www.nyfirearms.com/forums/ar...ber-vs-6-8spc-vs-300-blackout-vs-7-62x39.html

 

[Tim]

When it comes to the 6.8 you'll find most of your info at Activity Stream - Home of the 6.8 SPC - 68forums.com (I know both Mek and I frequent the site).

As for barrels you won't find a better value than the ones found there by a few of the regulars (Harrison from ar15performance.com is my preference. I have a 6.8 16" and a .223 wylde 16" from him). I also have his "superbolt" for the 6.8.

Keep an eye on his availability as it seems every month or so he gets batches done.

You'll find the 6.8 built in many lengths there. For my hunting I went mid length gas. Love the platform.

 

[Buell056]

Hey Tim thanks for the reference and site. Gonna do some reading after work today. Do I need a different buffer spring then those that come with say a Vltor stock.

 

[meketrefe]

When it comes to the 6.8 you'll find most of your info at Activity Stream - Home of the 6.8 SPC - 68forums.com (I know both Mek and I frequent the site).

As for barrels you won't find a better value than the ones found there by a few of the regulars (Harrison from ar15performance.com is my preference. I have a 6.8 16" and a .223 wylde 16" from him). I also have his "superbolt" for the 6.8.

Keep an eye on his availability as it seems every month or so he gets batches done.

You'll find the 6.8 built in many lengths there. For my hunting I went mid length gas. Love the platform.

I agree both ARP and also Bison Armory are great values. I have bought many barrels from ARP and many bolts and they are top quality cuts and finish. Bison also makes great parts. The issue right now is stock as they have a long wait list on many.
The round is brutal on deer and anything walking in the North East.

I think I am going to write a review on the 6.8SPC for this forum. That is long due.

 

[Buell056]

That would be sweet. You guys have any pics of deer post 6.8 SPC introduction?

 

[Tim]

That would be sweet. You guys have any pics of deer post 6.8 SPC introduction?

Nope, mine was only finished recently.

 

[Tim]

So now that I just picked up a stripped Mega upper, I'm gonna build it into a 6.8 SPC upper. I've reviewed the 6.5 as well as 300 blackout options but believe the 6.8 SPC will fulfill my swamp donkey slaying needs as well as others down the road.

Barrels: Have looked at JSE with 1:10 twist and liked what I read. Last build I used a PSA barrel in 5.56 and was satisfied with results but wondered if anyone has used JSE or another brand that worked out well. Looking for carbine length gas system but I guess midlength could work too. Just that midlength gas tubes etc are not as easy to find (I have seen them online but just thinking if I needed to swap parts between rifles might as well keep similar.

BCG: no where to start with this caliber. I have used WMD NiCorr BCGs on .223/5.56 builds and loved them but just looking again for other input.

Im pretty sure can use standard AR mags just need to change out follower for reliability. Any advice on gas blocks? I've used YAnkee Hill before but that's it. Any other input would be great.

OH oh oh oh - you DONT want to use standard AR mags.

They work yes ... barely and limit you (some factory produced ammo wont even fit). Don't use them!

Gas blocks - most of the barrels you find are drilled for standard size gas holes (depending on length). So whatever floats your boat/fits your configuration will work fine.

 

[JVG]

Rainier arms has 16" SPC barrels in stock

 

[Buell056]

Found the old thread about me considering building a 6.8 upper..... I'd still like to keep the wanted ad up jic someone has something for sale at a good price. Either way mags will be tough to find...

 

[DrgnFly]

Did you completely rule out 300Blk ?

I still want to build one. Either 8" or 10.2"

Eventually get a can, but that would be months after the build.

And yes this is a build once I move.

 

[cgrutt]

+1 ar15performance.com. they call their SPC an ARP but it is pretty much same as SPCII and will shoot standard SPC just fine. As others have said you will need barrel bolt and mags for 6.8. The BCG is standard except for the bolt itself. Definitely use mid or rifle length gas system. Recommend an 18 or 20 inch barrel as well.

 

[JamieZ]

Found the old thread about me considering building a 6.8 upper..... I'd still like to keep the wanted ad up jic someone has something for sale at a good price. Either way mags will be tough to find...

Mags are easy to find. Cproducts makes good 6.8 mags, they have them in stock at Midway and Aimsurplus. Aim doesnt have anything smaller than 10rnds.

 

[cgrutt]

I've picked up 6.8 mags from AIM, Wilson Combat, PRI before. I think Fulton Armory has them as well.

 

[Buell056]

I can also use a standard buffer / buffer spring as well?

 

[cgrutt]

I can also use a standard buffer / buffer spring as well?

Yes.