Help decide 6mm ARC barrel length

[troy fairweather]

I can't decide what barrel length to go with for my 6arc build, have a idea on the barrel brand thanks to loonwulf and its a great deal. But length I can't decide on, my mind wants me to get a 22" to get the most from the round out of the ad-15. But a 18" may look better and handle better even tho both barrels are hbars.

Real world the 22" maybe 100-125 fps faster then the 18" I only have 600 yards to shoot thanks to the new range opened near by, but most days will be under 300 yards. I plan to try some loads for varmints and deer.

Here's what I've got so far for the build.

Aero m4e1 lower.


San tan tactical pillar sst-15 upper.


Diamondhead bed-T 5.56 handguard 15" measures 16.5" at the bottom.


Vg6 gamma 65 break.


no butt stock yet, I'm thinking an A1 or A2

 

[gotboostvr]

I think either way that build is gonna look real good. I want to grab one of those Aero lowers even though I've got a bunch of Andersons ready to roll.

I would probably go with the 18" personally. Should still be plenty out to your intended ranges and it'll save a fair amount of weight and balance better.

 

[troy fairweather]

I think either way that build is gonna look real good. I want to grab one of those Aero lowers even though I've got a bunch of Andersons ready to roll.

I would probably go with the 18" personally. Should still be plenty of to your intended ranges and it'll save a fair amount of weight and balance better.

Nothing wrong with the Anderson's I do really like the m4e1 tho. The threaded holes in most everything is nice, looks better the a standard lower to. Fits my santantac and other standard aero uppers nice.

 

[LoonWulf]

22 personally, but again 99% of that is because I prefer the way it looks lol.

 

[troy fairweather]

The San tan tac upper has a pretty Unique look to it, feels really stiff.

 

[WisBorn]

Are the only options 18 or 22? Is a compromise length of 20" an option?
I like 20" on short action bolts like the model 7.
If you are pairing the rig with a long scope go long barrel. If the scope is going to be compact or a red dot stick with a 18".

Enjoy your build Troy!!!

 

[Varminterror]

What’s your target or tolerance for weight? Even shooting 300-600 yards, I’d likely build a heavy, well balanced, 24” semi-bull or bull barrel 6 ARC… but I also know I could shoot 300-600yards and enjoy the day with an ARC in 10.5” - it just wouldn’t balance and drive worth a damned to do the job.

My default “using rifle” barrel is 20” rifle length (might do a +1-2” on ARC) in a DCM/NM contour - heavy behind the block, .750” forward of the block. Not great at anything in particular, but heavy and long enough to be pretty stable on target, but light and handy enough to be ported for hunting.

 

[troy fairweather]

Are the only options 18 or 22? Is a compromise length of 20" an option?
I like 20" on short action bolts like the model 7.
If you are pairing the rig with a long scope go long barrel. If the scope is going to be compact or a red dot stick with a 18".

Enjoy your build Troy!!!

With the Shaw barrels there's only 18 and 22. I like the grendel hunter barrels to, and if I was going light is get one of there 18" . The Shaw will be almost $50 less then the hunters. I like the faxon to but the 1-8 the best 1-7.5 I feel better even though the heaviest I'll probably shoot is the factory 108. I think this would do some work on varmints, think guys are pushing the 55 grainers at 3600 something, not sure how feeding is tho. But I'll use 75-100 the most I think.

For a scope I want more a target scope, loonwulf said he has a 3-15 and that would work nice. I'll have to start looking at a 30mm ar mount to.

 

[troy fairweather]

What’s your target or tolerance for weight? Even shooting 300-600 yards, I’d likely build a heavy, well balanced, 24” semi-bull or bull barrel 6 ARC… but I also know I could shoot 300-600yards and enjoy the day with an ARC in 10.5” - it just wouldn’t balance and drive worth a damned to do the job.

My default “using rifle” barrel is 20” rifle length (might do a +1-2” on ARC) in a DCM/NM contour - heavy behind the block, .750” forward of the block. Not great at anything in particular, but heavy and long enough to be pretty stable on target, but light and handy enough to be ported for hunting.

Not to sure on the weight, just not super heavy. Around 10lbs maybe. All the parts I have aren't very light, that daimondhead rail is pretty heavy but very Comfy. Even the lower and upper are a few oz heavier then mili spec stuff.

The new range that opened is 600 yards and they have a lot of different steel to shoot, looked like 6" to half Silhouette maybe bigger. It will be a fun gun but do some hunting, but most work will be from a bipod or bench .

 

[troy fairweather]

Here's the Shaw barrel, think they have the same picture for the 18 and 22. This looks like a 16" to me tho.

 

[Varminterror]

most work will be from a bipod or bench .

This says >20” for me. Get that weight out there on the bipod.

 

[troy fairweather]

I can get a deal on the Odin barrels to, so that still in my mind. There a heavy barrel.

 

[LoonWulf]

Scopes an S-tac 3-16x42, weights about 24oz.....ill see what mounts ive got, don't think ive got a single piece, but might have some cheap xxxxxxxxx high chicoms thatll get u thru for a bit.

 

[troy fairweather]

Scopes an S-tac 3-16x42, weights about 24oz.....ill see what mounts ive got, don't think ive got a single piece, but might have some cheap xxxxxxxxx high chicoms thatll get u thru for a bit.

Cool thanks, ya I don't got anymore 30mm stuff, I had the 30mm leupold rings but gave them to a member here after I sold my swfa.

 

[WisBorn]

Nice looking scope. With the 600 yard range and the weight of a rifle/scope I would lean to the longer barrel. Take the extra velocity and reach out and touch some of those farm land coyotes.

 

[WisBorn]

Troy, I don't want to high jack or thread. Just q quick question. Were does the S-Tac 3-16x42 fall in comparison to a Leopold.

 

[Gtscotty]

I have a 21" Odin works and just put together a lighter weight 18" X-Caliber barreled upper for more general purpose and hunting work. I've only had the new 18" rig out once, but it was doing about 3/4" with factory 108gr. Not quite as good with 105gr, but still fine for a break-in outing. I ran a few loads with LVR and 100gr TGKs as well and think I have a good spot to flesh out a deer load on this next outing. I think it's going to be a good shooter for my purposes.

My Odin works in .223 has been very accurate and consistent, but the 6mm ARC hasn't been as consistent, it's also a heavy pig, I wouldn't go that route again. It's also worth mentioning that Odin Works was using a +2 gas system on their 18" barrels and some folks seemed to have cycling reliability issues.

Edit to add a few pics of the 18" upper and assembled at the range.

 

[troy fairweather]

Troy, I don't want to high jack or thread. Just q quick question. Were does the S-Tac 3-16x42 fall in comparison to a Leopold.

Good question, the is why I'd like to try this scope out, sightron is one of them scopes I know basically nothing about and I can't place it in my head. I've never heard much anything bad about them other then normal nit picking like any other scope. These seem to be well liked for the money and camrealand is running a really nice deal on the 2nd focal plane scopes now. I believe these are made in the Philippines, some maybe better then the average China scope.

 

[troy fairweather]

I have a 21" Odin works and just put together a lighter weight 18" X-Caliber barreled upper for more general purpose and hunting work. I've only had the new 18" rig out once, but it was doing about 3/4" with factory 108gr. Not quite as good with 105gr, but still fine for a break-in outing. I ran a few loads with LVR and 100gr TGKs as well and think I have a good spot to flesh out a deer load on this next outing. I think it's going to be a good shooter for my purposes.

My Odin works in .223 has been very accurate and consistent, but the 6mm ARC hasn't been as consistent, it's also a heavy pig, I wouldn't go that route again. It's also worth mentioning that Odin Works was using a +2 gas system on their 18" barrels and some folks seemed to have cycling reliability issues.

Edit to add a few pics of the 18" upper and assembled at the range.

View attachment 1100129 View attachment 1100130 View attachment 1100131

That swfa looks nice on that rig, man there a great scope have to get another some day. The gas thing with the 18" odin is what I was worried about, a lot say there way under gassed even with there block opened up. Was reading the 105 ammo is really hot, you seeing that. Some were saying it was killing the brass for reloads. It's a dollar a box more for the 108 at my lgc over the 105s so maybe I'll get the 108s to be safe.

 

[citizenconn]

I waited a long time to get a 6 ARC until I could find the barrel and twist rate I wanted. I got 3 Shilen 18" barrels with matched bolts for my first builds. Why 3? I always start with 2 of any new AR chambering. The 3rd goes to my reloader (Dad) so he will have something to test his loads in plus it gets him invested in to the chambering. Two builds with the same barrel lets me change a few variables and see the capabilities of the chambering.

18" is a good compromise for these type of AR chamberings (6.5 GR, .224 V, .223 W) whether hunting, target shooting, or whatever. Not too long for vehicle transport and not too heavy to carry but still long enough to get decent velocity. If I decide I like the 6 ARC I'll build others in 20 & 24" as well for bench shooting, maybe 22" if I find a good barrel, same as I do for all my target ARs.

I also like and use Aero receivers, both upper and lower (prefer the M4E1 enhanced versions). I have a number of those VG6 brakes on my 6.5 Grendel rifles. Even though they market them mainly for the 6.5 CR; I find them a little light for the Creedmoor, but they should be good for the 6 ARC.

Good luck; let us know how the build ends up.

 

[Varminterror]

That Shaw photo looks to be carbine length gas on an 18”, or maybe a 16” generic photo.

For 6 ARC, I wouldn’t use anything shorter than rifle length gas, and preferably rifle+1-2”.

The description above of issues with an Odin Works barrel is pretty consistent with my own experience with their stuff. When it works, it works, but pretty frequently, it doesn’t.

 

[troy fairweather]

That Shaw photo looks to be carbine length gas on an 18”, or maybe a 16” generic photo.

For 6 ARC, I wouldn’t use anything shorter than rifle length gas, and preferably rifle+1-2”.

The description above of issues with an Odin Works barrel is pretty consistent with my own experience with their stuff. When it works, it works, but pretty frequently, it doesn’t.

Ya a generic picture, not sure why they seem to be making a bunch of these. Shaw says these are rifle gas. I was ready last week to order a 18" grendel hunter barrel but they use a intermediate gas tube, I really wanted rifle or longer like you said .

 

[Gtscotty]

Btw, X-Caliber has one of their frequent 20% sales going on now, you could order exactly what you want for $275 + shipping if you can wait a little while to get it.

I went RLGS on my 18", and it was doing well with an SA bleed off about 8.5 turns out, which is about where I run my Grendel and .223s. +1 would probably be good, but wasn't an option, I'd go +2 for longer barrels (my +2 21" is very smooth shooting and hasn't bobbled).

I haven't noticed the Hornady black being particularly hot, the first batch or two were loaded a bit long and were in the lands on some rifles, but they fixed that a while ago.

 

[adcoch1]

Shaw just got the nod on a new barrel for me a few minutes ago, and 15% off didn't hurt. If I was you I'd go at least 20", so I vote 22". Going to be a nice rig...

 

[troy fairweather]

Shaw just got the nod on a new barrel for me a few minutes ago, and 15% off didn't hurt. If I was you I'd go at least 20", so I vote 22". Going to be a nice rig...

Even with the 15% it's still $10 more I could get one before the sale, I'll have to see if it's even cheaper now with the sale dropping this afternoon. Kinda wish I had the money for a 223W 18-20" barrel as Well. Was going to build one after this arc is done.