AR-10 Barrel

[Ed Compton]

I’m looking at buying an AR-10 barrel in .308 and have more or less narrowed my options down to a 20” Krieger 1:11 M110 profile ($650, no bolt) and a 20” Shilen 1:10 full length tactical profile ($550, bolt included). I want the rifle to be a multi-purpose long range rig, not to bulky to carry around and not so light that it can’t shoot long strings accurately. I’d like to hear thoughts on these brands in general and on these two profiles. Thanks

 

[DCC83501]

I cannot give you direct info on the .308 barrels but can share thoughts on Creeds. I've built three AR10's (6.5 Creed, 6 Creed, and 22 Creed). The 6 and 22 are both 18" X-Caliber barrels and "Sporter" profile. Developed loads that hammer coyotes! AR10's are HEAVY as compared to AR15's. Just point that out as some don't see that coming for some reason. Sorry for not answering your direct question but the weight thing is real.

 

[db2000]

1:10 twist and should 185 Juggs
I have 18” Proof CF and no issues with 10 shot strings at 1000

 

[Ed Compton]

I cannot give you direct info on the .308 barrels but can share thoughts on Creeds. I've built three AR10's (6.5 Creed, 6 Creed, and 22 Creed). The 6 and 22 are both 18" X-Caliber barrels and "Sporter" profile. Developed loads that hammer coyotes! AR10's are HEAVY as compared to AR15's. Just point that out as some don't see that coming for some reason. Sorry for not answering your direct question but the weight thing is real.

I have an M1A in a precision stock that weighs like 12lb no scope. I hate a few things about it but weight is not really one of them. I’m set up to reload.308 and everyone I shoot with has one so I’m gonna stick with it

 

[Ed Compton]

1:10 twist and should 185 Juggs
I have 18” Proof CF and no issues with 10 shot strings at 1000

I just graduated high school, I don’t have Proof CF money, but I wish I did and hope I will in the future. I’m sure they’re awesome

 

[db2000]

I just graduated high school, I don’t have Proof CF money, but I wish I did and hope I will in the future. I’m sure they’re awesome

Fair enough. You’re way ahead of me straight outta high school! Either of those barrels will be excellent. I prefer 1:10” for heavies

 

[JS8588]

I just graduated high school, I don’t have Proof CF money, but I wish I did and hope I will in the future. I’m sure they’re awesome

For what you're looking for, I have a feeling this would do you just fine. https://www.opticsplanet.com/lothar...arrel.html?_iv_code=3ZH-ATB-AR1-A0-N-P-030-10

 

[AMGtuned]

For what you're looking for, I have a feeling this would do you just fine. https://www.opticsplanet.com/lothar...arrel.html?_iv_code=3ZH-ATB-AR1-A0-N-P-030-10

My AR10 has a 20" L/W 1:10 RLGS; absolutely love it.

 

[BCP]

I have an M1A in a precision stock that weighs like 12lb no scope. I hate a few things about it but weight is not really one of them. I’m set up to reload.308 and everyone I shoot with has one so I’m gonna stick with it

What parts do you have already? And do you need a DPMS or Armalite pattern barrel?

I would go no longer than 16" if you don't like heavy rifles and be picky about handguard, stock, scope choices to keep weight from getting too astronomical.

 

[Cascade Hemi]

There is a significant difference between Krieger and Shilen in terms of quality. I like Shilen barrels but they are on par with Criterion, not Krieger.

If you're not in a hurry, X-Caliber will make you a semi custom button riffled barrel for under $400. They have 20% off sales every holiday weekend. Otherwise, Criterion has what you're looking for for much less money than Shilen.

Proof stainless barrels used to be the best deal going but they've jumped up a lot in the last few years.

 

[RUTGERS95]

man, if you're just punching paper and steel long range, you don't need to spend for that. There are other options but that said, the lothar barrel posted earlier is the absolute home run here. I may buy one just because

 

[Ed Compton]

There is a significant difference between Krieger and Shilen in terms of quality. I like Shilen barrels but they are on par with Criterion, not Krieger.

If you're not in a hurry, X-Caliber will make you a semi custom button riffled barrel for under $400. They have 20% off sales every holiday weekend. Otherwise, Criterion has what you're looking for for much less money than Shilen.

Proof stainless barrels used to be the best deal going but they've jumped up a lot in the last few years.

From what I can tell a criterion 20” is about $500 with a headspaced bolt. I can a shilen of the same length for the same price from Midway. Which is the better option?

 

[Ed Compton]

My AR10 has a 20" L/W 1:10 RLGS; absolutely love it.

I don’t think it comes with a headspaced bolt. Is that important though?

 

[Cascade Hemi]

From what I can tell a criterion 20” is about $500 with a headspaced bolt. I can a shilen of the same length for the same price from Midway. Which is the better option?

1020S-HYR - Criterion Barrels 20" .308 M118 Hybrid Stainless Rifle Length Barrel - AR15Discounts

Our .308 AR match grade barrels feature the M118 LR match chamber that is compatible with both 7.62×51 NATO and .308 Win ammunition and is optimized f

ar15discounts.com

https://www.armorally.com/shop/toolcraft-ar10-308-bolt-kit/

Including a headspaced bolt usually just means they are selling you a full priced bolt.

 

[Ed Compton]

1020S-HYR - Criterion Barrels 20" .308 M118 Hybrid Stainless Rifle Length Barrel - AR15Discounts

Our .308 AR match grade barrels feature the M118 LR match chamber that is compatible with both 7.62×51 NATO and .308 Win ammunition and is optimized f

ar15discounts.com

https://www.armorally.com/shop/toolcraft-ar10-308-bolt-kit/

Including a headspaced bolt usually just means they are selling you a full priced bolt.

I had planned on buying an Aero BCG, would that bolt work?

 

[5RWill]

1:10 twist and should 185 Juggs
I have 18” Proof CF and no issues with 10 shot strings at 1000

How is your velocity on the 185gr juggs? Just picked up 80rds of FGMM for $1.50/rd. Though with the introduction of the 174gr ELD VT i think it will be my go to 30 cal round from now on.

 

[Cascade Hemi]

I had planned on buying an Aero BCG, would that bolt work?

Just buy the entire BCG at one time. Source it from whomever you think is best. Here is a source for the complete TooCraft double ejector BCG. They are very good for the money, probably as good as JP for less than half the price. Swap out the ring and extractor spring with SprinCo.

https://www.armorally.com/shop/toolcraft-6-5-creedmoor-nickel-boron-double-ejector-bcg/

 

[JS8588]

I don’t think it comes with a headspaced bolt. Is that important though?

The same barrel on LWs website *does* come with the bolt
https://www.lothar-walther.com/905/...on-mud-5/8-24-unef-2a-l-18.00-cr-moly-s?c=282 I believe you'd get it with the OP listing as well. That said...

I had planned on buying an Aero BCG, would that bolt work?

I've heard a lot of problems with Aero large frame BCGs. What I would (and will, as I'm in the planning stages of an AR308 build myself. See this post) do, is buy the Lantac Enhanced BCG. They're OOS pretty much everywhere at the moment, but they seem to offer better reliability in large frame gassers and may give you a little more accuracy since it's a supported tail carrier.

Also going to use this receiver set.

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

bkingsfirearms.com

Thermal fit, ambi controls, sub $300? Can't imagine doing better.

 

[sinister]

The Krieger cut-rifled barrel is your best option for precision, but not necessarily so for balance and weight if you're planning to use it for anything but prone shooting off a bipod.

The Walther barrel mentioned above is also a superior choice.

Criterions and Shilens are good to very good barrels but not necessarily in the same league as the Krieger. Proof barrels are also cut-rifled, but carbon-fiber wrapping can double your cost.

 

[db2000]

How is your velocity on the 185gr juggs? Just picked up 80rds of FGMM for $1.50/rd. Though with the introduction of the 174gr ELD VT i think it will be my go to 30 cal round from now on.

2520 Seekins AR10 18” proof 43 Varget
2680 24” Savage APO rifle 43.5 Varget
2620 Savage w/ FGMM factory ammo

 

[Ed Compton]

The same barrel on LWs website *does* come with the bolt
https://www.lothar-walther.com/905/...on-mud-5/8-24-unef-2a-l-18.00-cr-moly-s?c=282 I believe you'd get it with the OP listing as well. That said...

I've heard a lot of problems with Aero large frame BCGs. What I would (and will, as I'm in the planning stages of an AR308 build myself. See this post) do, is buy the Lantac Enhanced BCG. They're OOS pretty much everywhere at the moment, but they seem to offer better reliability in large frame gassers and may give you a little more accuracy since it's a supported tail carrier.

Also going to use this receiver set.

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

bkingsfirearms.com

Thermal fit, ambi controls, sub $300? Can't imagine doing better.

Only thing with the Aero M5 is you can get the enhanced version and have a truly free floating hand guard

 

[JS8588]

Only thing with the Aero M5 is you can get the enhanced version and have a truly free floating hand guard

Free float/Thermal fit. It's sixes. You don't have a bad choice between em.

 

[Ed Compton]

Free float/Thermal fit. It's sixes. You don't have a bad choice between em.

What is the thermal fit and what would you think about this for a BCG?https://www.armorally.com/shop/toolcraft-ar10-308-double-ejector-bcg/

 

[Ed Compton]

The toolcraft is almost half the price of the lantac

 

[Ed Compton]

Free float/Thermal fit. It's sixes. You don't have a bad choice between em.

I assume I could buy just their ambi lower and stick an M5E1 upper on it, right?

 

[Cascade Hemi]

What is the thermal fit and what would you think about this for a BCG?https://www.armorally.com/shop/toolcraft-ar10-308-double-ejector-bcg/

There is an interference between the OD of the barrel and the ID of the receiver. It's called thermal fitting because you heat the receiver to slide in the barrel. Do a search in this section for barrel bedding and you will find more detailed information, including how to shim a non interference fit receiver and barrel.

 

[AMGtuned]

I don’t think it comes with a headspaced bolt. Is that important though?

I used a Toolkraft (sp) complete bcg, with the nickel coating. I had and continue to have, no problems. YMMV. I think this has been answered now though.

 

[RUTGERS95]

The same barrel on LWs website *does* come with the bolt
https://www.lothar-walther.com/905/...on-mud-5/8-24-unef-2a-l-18.00-cr-moly-s?c=282 I believe you'd get it with the OP listing as well. That said...

I've heard a lot of problems with Aero large frame BCGs. What I would (and will, as I'm in the planning stages of an AR308 build myself. See this post) do, is buy the Lantac Enhanced BCG. They're OOS pretty much everywhere at the moment, but they seem to offer better reliability in large frame gassers and may give you a little more accuracy since it's a supported tail carrier.

Also going to use this receiver set.

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

BKF M5 MOD-0 LR-308 Stripped Billet Receiver Set W/ Ambi Bolt Release

bkingsfirearms.com

Thermal fit, ambi controls, sub $300? Can't imagine doing better.

I don't know, through 5 builds I've not had a single issue with Aero large frame bcg's. hell, the torture test went 3600rds of no lube before the firing pin failed. I'd say they are gtg

kid needs to spend his money on a quality barrel and ammo

 

[Ed Compton]

Would I need to get a set of headspace guages?

 

[JS8588]

I assume I could buy just their ambi lower and stick an M5E1 upper on it, right?

You absolutely could.
I also recommend reading this

Accurize Your AR-15 - Guns and Ammo

Guns & Ammo editor Joseph Von Benedikt takes a look at four steps to increase precision on your personal AR-15.

www.gunsandammo.com

 

[JS8588]

I don't know, through 5 builds I've not had a single issue with Aero large frame bcg's. hell, the torture test went 3600rds of no lube before the firing pin failed. I'd say they are gtg

kid needs to spend his money on a quality barrel and ammo

I'd go with the Toolcraft or KAK before Aero.

As to how he spends his $, you're not wrong.

 

[Flyingbullseye]

Ed, if you're interested I have an extra LFAR Loather Walther .308 barrel, headspaced bolt with a very low count I'd be willing to part with.

If not go krieger if you can find one

 

[BCP]

I would get a barrel with a matched bolt if possible.

 

[padom]

Krieger and Bartlein are going to be your best of the best. I have 10-12 in the safe in 308 and 6.5cm on multiple MEGA uppers

Headspace bolt for sure, only way I role.

In regards to BCG, I'm a JP or RCA only guy.
The RCA HM coated High Pressure bcg are top of the line.

Little secret, you can buy their 350 398 HP+ BCG for $180 here. They call it their blem, not mechanically but laser engraving, cosmetic they say. Guess what, I've bought tons of these, I've never had one arrive that looked anything different than my non-blems. Same box, nothing wrong with it.

Also, they say backorder. I place an order many times on these blems that say backorder and they all shipped in a few days

*BLEM* Standard Mass AR-10 .308 Win+ Multi HP Calibers DPMS complete W/ Assist - Welcome to Rubber City Armory

This is a COSMETIC BLEMISHED complete DPMS style BCG with Blacknitride+ finish - PLEASE NOTE - ITEM MAY HAVE IMPERFECT LASER ENGRAVING, OR COSMETIC IMPERFECTIONS BUT IS OPERATIONALLY CORRECT. ALL RCA WARRANTIES STILL APPLY. PLEASE NOTATE IN THE ORDER NOTES IF YOU WISH YOUR CARRIER TO BE...

rubbercityarmory.com

 

[91Eunozs]

+1 on the Bartlein recommendation, but Criterion, Shilen, etc. should do well …as well. LOL

Also, the KAK bolt with the double ejectors has worked great for me; absolutely fixed an occasional FTE malfunction I used to get with standard bolts.

My home-brewed AR10 was built primarily for light weight hiking through scrub brush, with most shots taken well within a couple hundred yards…usually inside 100 yards…so it’s rockin’ a 16” Faxon pencil profile barrel. Not the best for accuracy, but accurate enough for my needs; minute of pig or coyote within a couple hundred yards.

I’m currently running that bolt in a V7 titanium carrier…had to play around with the adjustable gas block a bit after getting the buffer weight right for my preference, but it works great.

Huge weight difference between a standard BCG like the KAK, and the V7:

vs.

 

[Ed Compton]

Krieger and Bartlein are going to be your best of the best. I have 10-12 in the safe in 308 and 6.5cm on multiple MEGA uppers

Headspace bolt for sure, only way I role.

In regards to BCG, I'm a JP or RCA only guy.
The RCA HM coated High Pressure bcg are top of the line.

Little secret, you can buy their 350 398 HP+ BCG for $180 here. They call it their blem, not mechanically but laser engraving, cosmetic they say. Guess what, I've bought tons of these, I've never had one arrive that looked anything different than my non-blems. Same box, nothing wrong with it.

Also, they say backorder. I place an order many times on these blems that say backorder and they all shipped in a few days

*BLEM* Standard Mass AR-10 .308 Win+ Multi HP Calibers DPMS complete W/ Assist - Welcome to Rubber City Armory

This is a COSMETIC BLEMISHED complete DPMS style BCG with Blacknitride+ finish - PLEASE NOTE - ITEM MAY HAVE IMPERFECT LASER ENGRAVING, OR COSMETIC IMPERFECTIONS BUT IS OPERATIONALLY CORRECT. ALL RCA WARRANTIES STILL APPLY. PLEASE NOTATE IN THE ORDER NOTES IF YOU WISH YOUR CARRIER TO BE...

rubbercityarmory.com

Would you pick the RCA over the toolcraft dual ejector BCG?

 

[Cascade Hemi]

Would I need to get a set of headspace guages?

You're going to get a lot of opinions. I have gages and I headspace everything. I can't recall the last time I've had one fail the gages. It does happen but generally not with brands you're looking at. If I were building a single rifle, I wouldn't bother. Just shoot it and assess the brass. If you end up building more rifles and need to set HS yourself, buy gages at that time.

 

[bfoosh006]

IMHO, Azimuth Technology makes the .... ( with current FP tip size and bolt face hole diameter ... )
Azimuth makes other folks BCG's as well Wilson Combat, Battle Arms development , CMC / SanTan

.Aero Nitrited and phosphated 308 BCG's,... TAPERED SD FP tip size... .068" .... Bolt face hole... .070"

The KAK dual ejector, I haven't checked this one yet... I am hoping it will go on sale during the 4th Weekend.

The Rubber City Armory HP.... Proprietary SD Non-Tapered FP... .066" , Bolt face hole... .071" ( to much slack for my preference in this current lot

CMC / Santan complete 308 BCG.....Tapered FP SD Tip... .067".... bolt face FP hole... .070"

Lantac's expensive Enhanced 308 BCG uses a smaller diameter FP and bolt hole...Tapered SD FP tip size... ( 2x ) .067.... Bolt face FP hole... .070"
BUT, the available Lantac replacement M-Spec bolt and FP are larger....
Lantac 308 FP , Nib 308 Bolt, and Nitrated 308 bolt, .... .076" FP tip size ( 4ea ) .081" Bolt FP hole on both... these are sold as "spare parts".
Standard style. ( Non Tapered )
PSA / Toolcraft 308 BCG... FP tip size.. .077" , bolt FP hole... .081
10ea PSA FP measured.. varied between .076" ( 2ea ) .077" ( 7ea )and .079" ( 1ea )
Standard style. ( Non Tapered )

PSA / Toolcraft 6.5CM Dual ejector BCG...Tapered SD Tip FP... .068 and .069" , Bolt face FP hole... .071"


More info over here... https://www.snipershide.com/shooting/threads/308-6-5cm-fp-tip-sizes-and-the-variety-i-found.7222014/

Ultimately... there is a lot of mix and match going on with parts.

 

[bfoosh006]

For the OP... I think you would be just fine with a Aero Nitrided or phosphated 308 BCG,
https://www.aeroprecisionusa.com/catalog/product/view/id/536/s/308-bcg-black-nitride/category/201/


Or a PSA / Toolcraft dual ejector w/ small diameter FP
https://palmettostatearmory.com/psa-nitride-6-5-creedmoore-bcg-with-double-ejector.html

 

[Ed Compton]

What are y’all’s thoughts on the Fulton Armory BCG?

 

[BCP]

Nothing wrong with fultons stuff other than it being a bit overpriced/poor availability on some items. The barrels are criterion and they will sell you a headspaced bolt for an extra 100 bucks. I had an AR10 with a fulton stainless barrel and it shot tiny groups.

If you haven't bought ANY parts yet whatsoever you should take a look at the armalites on sale at palmetto. The 16" is 1200$ on the off chance it doesn't shoot well then get a custom barrel headspaced to your bolt and gtg.

 

[Ed Compton]

Also, how nice is it to have the fully ambidextrous lower? I had planned on just buying a complete lower from Aero and putting a better trigger in it, but if that is a genuinely good feature worth building the lower I would be willing to do it.

 

[Flyingbullseye]

Also, how nice is it to have the fully ambidextrous lower? I had planned on just buying a complete lower from Aero and putting a better trigger in it, but if that is a genuinely good feature worth building the lower I would be willing to do it.

For a DMR/SPR type build I'd recommend one but isn't the most important feature. It took me a while to get used to one. Wasn't paying attention and would occasionally release the mag instead of the bolt. Besides that its nice to just use your right index finger to release the bolt instead of doing the old reach around.

 

[Ed Compton]

I’ve made up my mind in pretty much everything except for the bolt BCG. I don’t want to buy a nice bolt carrier and bolt and then replace that bolt with the generic fulton headspaced one that I could get with the Criterion, and I also would prefer not to spend $200 on the JP bolt they offer. However, if I could get away without buying a headspaced bolt I would just go with a toolcraft or the RCA blem. Thoughts? Stuff I’ve read has been highly contradictory. I’m hoping to order parts this evening or tomorrow.

 

[padom]

Youll be fine. RCA and JP are widely used bolts companies worth a damn use to headspace their barrels to. I have been personally told this by multiple barrel companies.

Get the RCA blem, you will love it. Top notch lifetime warranty and the HM coating makes cleaning super easy. Slick as snot, wipes right off.


Ill get a step further and also know you can do this later if you dont want to know but its an AWESOME cheap upgrade that can make turing your new custom build even better.

I have used adjustable gas blocks for a LONG time. Was a necessity for me when building any custom AR to fine tune the gas. I have used ALL the top names. They all eventually seize and need replaced or rebuild kits. You can prolong this be cleaning and moving the adjustment screw in both directions after each range session then back to your setting.

Its been a few years since I made the switch on all my AR15 and AR10 builds to Rubber City's adjustable gas key. I fixed low profile regular gas blocks on all my custom builds with the RCA AGK.

RCA Adjustable Gas Key - Welcome to Rubber City Armory

Made from Pre-Hardened 4140: 28-32RC with radiused corners reducing sharp edges. Enhances performance of low mass and standard mass GI systems without unnecessary dissassembly. Gas flow is adjusted and maintained at the carrier with set screws. One to adjust gas flow and one to lock it in place...

rubbercityarmory.com

It is stupid easy and fast to adjust/tune and works excellent. Zero issues in the 3 years or so Ive been using them and I have them on my AR10 308's, 6.5cm, SBR's, 16" AR's. Zero issues, tune super fast and work great.

You can even place your order and call RCA (great people and great customer service by the way every time Ive talked to them) and ask them to install the adjustable gas key on the blem carrier before they ship it if you would rather they do it....

To tune, you take the tuning screw and screw it all the way into the adjustable gas key until it stops. You then turn it back out 1 full turn. This gets you very close. You then turn it out 1/4 turn at a time to open the gas more or in 1/4 turn at a time to close the gas off more. Once your fully tuned where you want it, you install the lock screw and your done. I set mine where the gas allows my bolt to fully cycle and lock back on an empty mag. I will then go fire a 20-30rd or so, with only 5rds in the mag at a time to ensure every one feeds and the bolt locks back every time. Then lock it down.

 

[Ed Compton]

Youll be fine. RCA and JP are widely used bolts companies worth a damn use to headspace their barrels to. I have been personally told this by multiple barrel companies.

Get the RCA blem, you will love it. Top notch lifetime warranty and the HM coating makes cleaning super easy. Slick as snot, wipes right off.


Ill get a step further and also know you can do this later if you dont want to know but its an AWESOME cheap upgrade that can make turing your new custom build even better.

I have used adjustable gas blocks for a LONG time. Was a necessity for me when building any custom AR to fine tune the gas. I have used ALL the top names. They all eventually seize and need replaced or rebuild kits. You can prolong this be cleaning and moving the adjustment screw in both directions after each range session then back to your setting.

Its been a few years since I made the switch on all my AR15 and AR10 builds to Rubber City's adjustable gas key. I fixed low profile regular gas blocks on all my custom builds with the RCA AGK.

RCA Adjustable Gas Key - Welcome to Rubber City Armory

Made from Pre-Hardened 4140: 28-32RC with radiused corners reducing sharp edges. Enhances performance of low mass and standard mass GI systems without unnecessary dissassembly. Gas flow is adjusted and maintained at the carrier with set screws. One to adjust gas flow and one to lock it in place...

rubbercityarmory.com

It is stupid easy and fast to adjust/tune and works excellent. Zero issues in the 3 years or so Ive been using them and I have them on my AR10 308's, 6.5cm, SBR's, 16" AR's. Zero issues, tune super fast and work great.

You can even place your order and call RCA (great people and great customer service by the way every time Ive talked to them) and ask them to install the adjustable gas key on the blem carrier before they ship it if you would rather they do it....

To tune, you take the tuning screw and screw it all the way into the adjustable gas key until it stops. You then turn it back out 1 full turn. This gets you very close. You then turn it out 1/4 turn at a time to open the gas more or in 1/4 turn at a time to close the gas off more. Once your fully tuned where you want it, you install the lock screw and your done. I set mine where the gas allows my bolt to fully cycle and lock back on an empty mag. I will then go fire a 20-30rd or so, with only 5rds in the mag at a time to ensure every one feeds and the bolt locks back every time. Then lock it down.

So that acts as an adjustable gas block? I had planned on a superlative arms bleed-off gas block. They claim that it does not cause things to sieze. SA gas block

 

[45-90]

I’m looking at buying an AR-10 barrel in .308 and have more or less narrowed my options down to a 20” Krieger 1:11 M110 profile ($650, no bolt) and a 20” Shilen 1:10 full length tactical profile ($550, bolt included). I want the rifle to be a multi-purpose long range rig, not to bulky to carry around and not so light that it can’t shoot long strings accurately. I’d like to hear thoughts on these brands in general and on these two profiles. Thanks

I have a Schilen, Proof, Wilson Combat, barrels in AR 308.
The Wilson Combat is 16" fluted and has titanium bolt carrier & muzzle brake, magnesium upper, and carbon fiber handguard.
And weights 6 lbs 3 oz without scope.
And us capable .5" 5 shot groups at 100.
Easy to carry.
The Proof Research barrel is capable of 5 shots in .3" and .4" back to back, 18" its heavy but has the best all around accuracy.
The Schilen barrel is 24" comes with a bolt, and is generally the least accurate of the 3 but has loads it likes. I have several Schilen barrels that are more accurate than the 308 barrel...luck of the draw.
Had a heavy Ballistics Advantage that only liked one load ...sometimes, and generally about 1 in 3 has acceptable accuracy from BA. Faxon is about the same, in my experience.
I'd choose Proof Research SS barrel, but not the carbon wrapped barrel.

 

[bfoosh006]

So that acts as an adjustable gas block? I had planned on a superlative arms bleed-off gas block. They claim that it does not cause things to sieze. SA gas block

The RCA gas key adjustment is another way to restrict gas flow into the carrier. So , yes , it achieves a similar effect.
FWIW... if you order the RCA , you might consider ordering some spare screws and set screws... I promptly my set screws at the range , while adjusting it... Dooh.. ( and put them in your range bag. )
The ones they sell now have a spare set screw.
https://rubbercityarmory.com/product/replacement-set-screw-kit/

 

[padom]

So that acts as an adjustable gas block? I had planned on a superlative arms bleed-off gas block. They claim that it does not cause things to sieze. SA gas block

Yes, that's exactly what it does.

The SA AGB absolutely seizes eventually. I have been using them for years... also, you will need to make sure you purchase a large enough inner diameter handguard to clear that SA AGB and ensure it's not hitting under recoil which in turn fucks with your accuracy.

Just some things to note

 

[Cascade Hemi]

I’ve made up my mind in pretty much everything except for the bolt BCG. I don’t want to buy a nice bolt carrier and bolt and then replace that bolt with the generic fulton headspaced one that I could get with the Criterion, and I also would prefer not to spend $200 on the JP bolt they offer. However, if I could get away without buying a headspaced bolt I would just go with a toolcraft or the RCA blem. Thoughts? Stuff I’ve read has been highly contradictory. I’m hoping to order parts this evening or tomorrow.

IMO... order the BCG you want and headspace gage it later it if you have a problem. You can't change the headspace, checking it is purely diagnostic. I would be more concerned about HS if you were discussing a low end barrel.