6mm ARC bolt gun for competition?

patscrazy

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Mar 2, 2013
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I’m trying to dig more info on possibly switching up to 6mm arc for a competition bolt gun. I’m currently set up with a 6 creedmoor on a Curtis vector switch barrel in a foundation stock. I have zero issues running this caliber just thinking ahead.

I’m about half way through this barrels life with about 850 rounds and thinking of going to a dasher or maybe even the 6 arc for my next barrel. My thought process stems from the current trend of shooting a “slower” 6mm for easier follow up/seeing trace/splash for correction.

Something from the 6BR family is an obvious possibility but I’m interested in the 6 arc too. I know it would require a new bolt and dedicated mags or a mag kit.

Certainly not as popular as the GT or the 6BR family crowd but I’m sure there are some people out there running them with success. What are the Pros/cons in your experience?

Brass seems like a weak point in my uneducated view. I actually like to reload so that’s the plan regardless of caliber. So choices seem like having to buy Hornady 6 arc ammo to reuse the brass or resize quality 6.5 Grendel brass. Not sure what issues arise from the latter.

Any insight into this would be appreciated. Thanks.
 
In the process of doing it right now myself. I got my new bolt face in for my TL3 action and waiting on my PVA Osprey barrel in 6mm ARC to come in. Then I will pic up a couple MDT mags and wait for my ammo to come in. I figure if I can get the lighter loaded 108 ELDs going 2750fps in a 26" bolt gun I will be good and can load them a little faster.

I am sure you will get some coming in and telling you are crazy but I figure it's my time and money so I will give it a shot. LOL
 
I do not compete, but I own a 6 ARC bolt gun. I love it. It is a joy to shoot and efficient to reload.

But, the lack of quality brass (or any brass for that matter) would concern me if I shot the amount of ammo a competitor shoots. To get 6ARC headstamped brass, you really need to buy Hornady ammo because stand alone brass brass is not available in quantity.

Most of my 6ARC brass is converted Starline 6.5 Grendel brass.
 
Seems easy enough to covert. Any issues or inconsistencies with the converted Grendel brass?

The main issue is it is a PITA to go through all the steps and end up with brass that isn't as good as out of the box brass.

If I burn out the barrel, I'll replace it with a 6mm CM barrel unless good, out of the box brass becomes available.

If brass becomes available in reasonable quantities, I'll stick with the cartridge.
 
I know a guy who runs a 6ARC bolt gun and he's been doing good with it. As has been mentioned, the lack of brass out there is the main drawback right now, hopefully, that'll change.

I'm looking at possibly building one at some point. It seems like a good alternative to 6BR for someone looking for a 6mm case with less powder capacity and the option to run factory/off-the-shelf ammo if need be.

That said, I don't think the speed thing matters much anymore, and have even started to wonder if case-fill is as big of a deal as some make it out to be... my 6CM shoots great at 2850-2900fps and I still get single-digit SDs even though the cases are like 2/3 full and they sound like salt & pepper shakers.
 
In a bolt gun I can’t understand going to 6 arc unless you’re invested in the caliber for a gas gun already. It does nothing better than a 6br can do. Throw in the bolt cost that is really a loss because it’s no good for any other standard calibers, and it makes the decision even easier.

On the other hand, if you’re just wanting to do it because it’s neat and you don’t need to justify expense or hassle, sounds like a good plan.
 
6 ARC Seekins AR.
I have 80% loose primer pockets and a few that the primer just fell out after 4 reloads with Hornady Black brass. In fairness, it was probably the ones I loaded hot just to see what was possible. This seems like a questionable choice if you’re shooting as much as competition requires.
 
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Running 6arc as trainer and backup match rifle, ran 22 grendel last year. Have run 22br, 6br, GT, creedmoor etc. Peterson has 6arc in production. Starline grendel brass is awesome, especially for the price, yes converting that brass sucks. 2900 possible with 108s with 26” proof barrel, decent brass life and lever.

Cons-brass-at the moment. Shorter neck. Less case capacity. Not in widespread use/data
Plus-feeds better than br (Mdt mags), Off the shelf common Factory match ammo. 12 round mag same size as 10 for br
 
In a bolt gun I can’t understand going to 6 arc unless you’re invested in the caliber for a gas gun already. It does nothing better than a 6br can do. Throw in the bolt cost that is really a loss because it’s no good for any other standard calibers, and it makes the decision even easier.

On the other hand, if you’re just wanting to do it because it’s neat and you don’t need to justify expense or hassle, sounds like a good plan.

I liked my gas gun so much that I got a bolt gun.
 
The main issue is it is a PITA to go through all the steps and end up with brass that isn't as good as out of the box brass.

If I burn out the barrel, I'll replace it with a 6mm CM barrel unless good, out of the box brass becomes available.

If brass becomes available in reasonable quantities, I'll stick with the cartridge.
"All the steps" lube and fl size

What do you think is wrong with sized down grendal brass?

I have 7.62x39 brass I fire formed to grendel then sized and used in the 6mm arc.
 
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Yeah, I’m pretty sold on this cartridge. I have a Curtis vector with the quick change to make swapping barrels easier. Sure I’ll to deal with the added expense of a whole new bolt in order to run the 6 arc, but why not. Lapua 6.5 Grendel brass out there is good stuff. And the 6 arc brass is only going to improve in the near future.
 
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My parts are coming together. PVA Osprey prefit with some fluting should be here soon and then put it together. Looking forward to some fun!

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I do not compete, but I own a 6 ARC bolt gun. I love it. It is a joy to shoot and efficient to reload.

But, the lack of quality brass (or any brass for that matter) would concern me if I shot the amount of ammo a competitor shoots. To get 6ARC headstamped brass, you really need to buy Hornady ammo because stand alone brass brass is not available in quantity.

Most of my 6ARC brass is converted Starline 6.5 Grendel brass.
Peterson coming Q4
 
At the regional qualifier match I shot this past weekend I found some 6mm ARC brass laying around on the deck so seems like others are thinking about it also.
 
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Just got the notification my PVA 6mm ARC barrel ships tomorrow! Can't wait!
Rob, what are you using for bottom metal and mags?? I just ordered a Zermatt action and will be putting it into an older H&S stock. Haven't figured out what to use for bottom metal and what I should use for mags. Thank you!!!
 
Rob, what are you using for bottom metal and mags?? I just ordered a Zermatt action and will be putting it into an older H&S stock. Haven't figured out what to use for bottom metal and what I should use for mags. Thank you!!!
M5 and MDT mags I bet; that’s what I’m using.
 
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I hope we can read about updates from the field. I did not think of it in this vein. I know of a guy who has a CMMG 6 ARC (semi-auto) and he built it up as a truck gun good for varmints and up to whitetail deer.

So, this would be interesting to follow, as well.
 
Rob, what are you using for bottom metal and mags?? I just ordered a Zermatt action and will be putting it into an older H&S stock. Haven't figured out what to use for bottom metal and what I should use for mags. Thank you!!!

I use Manners stocks with their mini chassis in it so that is the bottom metal but I did buy MDT 12 round aics mags. The bottom metal mentioned above will work for you but might need some small fitting.

86A210FC-BC5E-44C0-9D1E-880953CDB780.jpeg
 
I see the major benefit over things like 6 BR(and family) or .223 AI / .224 Valk (as it dies out) as the availability of factory ammo. I know everyone loves the 6BR, but damn does it seem like work. Actually, it seems like you're shit out of luck if you don't reload and don't have the right action and mags to run it. That's the reason I have a 6CM instead. Doing it again today, maybe a tossup between 6CM and 6GT... but, if I didn't mind running a different bolt and a mag kit, I'd be happy to run the 6ARC.
 
I see the major benefit over things like 6 BR(and family) or .223 AI / .224 Valk (as it dies out) as the availability of factory ammo. I know everyone loves the 6BR, but damn does it seem like work. Actually, it seems like you're shit out of luck if you don't reload and don't have the right action and mags to run it. That's the reason I have a 6CM instead. Doing it again today, maybe a tossup between 6CM and 6GT... but, if I didn't mind running a different bolt and a mag kit, I'd be happy to run the 6ARC.
I have the 6.5 Creedmoor and love it!! I have an ARC in an AR with a proof barrel and it is a consistent .4 to .5 gun for 5 shots!!
 
If I ever get around to doing a Varget/6CM experiment and it works out, I'm going to shoot slow-ass 6CM using only 30-something grains... but if not, a 6ARC bolt gun may be on the horizon.

In my case, I go back and forth berween 6CM and 6GT, and 6GT has opened my eyes to me possibly going with an even smaller, more efficient, 6mm case that uses even less powder... but I'd like to keep using/shooting Proof prefits.

Proof doesn't makes prefits for 6BR... but they do for Dasher and 6ARC, and since everybody already shoots a Dasher and I figure if I'm going to buy a bunch of new shit in the name of going smaller/efficiant... 6ARC it is then (for now)!

The unproven mags scare me though...
 
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We will see how the mags work when I get to the range but I put one round in and ran the bolt and it fed perfectly so lets hope they both do. If not then a little tuning might be needed.
 
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Got out with it today. Both mags fed fine. Only put 20 rounds through it to get zeroed and test mags but shot out to 540 yards and it dropped where I aimed them. The factory 108 ammo was a little slow at 2670fps but as barrel works in it should get up over 2700fps and that was only one lot I had so I will test the other one next time out. Recoil was very light which was nice.
 
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Got out with it today. Both mags fed fine. Only put 20 rounds through it to get zeroed and test mags but shot out to 540 yards and it dropped where I aimed them. The factory 108 ammo was a little slow at 2670fps but as barrel works in it should get up over 2700fps and that was only one lot I had so I will test the other one next time out. Recoil was very light which was nice.

With the right power Hornady says you can get 2850 with the 108's. 2800 is very doable with hand loads made using their "bolt gun" data.
 
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With the right power Hornady says you can get 2850 with the 108's. 2800 is very doable with hand loads made using their "bolt gun" data.

Yeah loading I am not too worried about getting near 2800fps but was hoping for a little more speed from factory.
 
I see the major benefit over things like 6 BR(and family) or .223 AI / .224 Valk (as it dies out) as the availability of factory ammo. I know everyone loves the 6BR, but damn does it seem like work. Actually, it seems like you're shit out of luck if you don't reload and don't have the right action and mags to run it. That's the reason I have a 6CM instead. Doing it again today, maybe a tossup between 6CM and 6GT... but, if I didn't mind running a different bolt and a mag kit, I'd be happy to run the 6ARC.
What work? 6 BR, Dasher and GT are some of the EASIEST cartridges to load for. As long as you use good componets, its hard not to make a load that doesn't shoot inside half a moa, and 3/8 and under is the rule, not the exception.

I just dont understand the fascination with 6 ARC in a Bolt gun. In an AR platform, where you are limited to an AR magwell and COAL, Its an absolute monster of a cartridge and makes perfect sense if you want to hunt or compete with a small frame AR. But in a bolt gun, you are stuck with shitty brass and even less case capacity than the 6 BR family, which already have the mags and the feeding issues worked out for the most part using AW or AICS mags.

Anyone wanting a 6 ARC bolt gun is MUCH better off going BR. The difference between Lapua/Alpha and Hornady Brass is night and day. You can load to a higher velocity, using less pressure which all things being equal, means better barrel life. It also means you are blowing out shitty hornady primer pockets that much faster trying to keep up. You have established dies from the top manufactures to choose from. Not to mention you need a different bolt, so it costs even more. It makes no sense other that doing it for the sake of doing it.
 
What work? 6 BR, Dasher and GT are some of the EASIEST cartridges to load for. As long as you use good componets, its hard not to make a load that doesn't shoot inside half a moa, and 3/8 and under is the rule, not the exception.

I just dont understand the fascination with 6 ARC in a Bolt gun. In an AR platform, where you are limited to an AR magwell and COAL, Its an absolute monster of a cartridge and makes perfect sense if you want to hunt or compete with a small frame AR. But in a bolt gun, you are stuck with shitty brass and even less case capacity than the 6 BR family, which already have the mags and the feeding issues worked out for the most part using AW or AICS mags.

Anyone wanting a 6 ARC bolt gun is MUCH better off going BR. The difference between Lapua/Alpha and Hornady Brass is night and day. You can load to a higher velocity, using less pressure which all things being equal, means better barrel life. It also means you are blowing out shitty hornady primer pockets that much faster trying to keep up. You have established dies from the top manufactures to choose from. Not to mention you need a different bolt, so it costs even more. It makes no sense other that doing it for the sake of doing it.

I think a case to be made for the 6ARC bolt gun is: everybody and their brother already has like ~12 ARs while only a relative handful of guys who are already balls-deep into shooting bolt guns have 6BRs... so over the next couple of years we don't need a crystal ball to know which one is going to proliferate.

It seems like the name of the game is guys are trying to use the most efficient case and the least amount of powder possible (yielding less recoil and making it easier to spot shots) to send a 6mm projectile out to ~1200 yards or so, and while a 6BR already can do that, 6ARC can do it with a little less powder and fits in Tactical Timmy's AR, so the gun market already loves it...
 
Maybe for someone just starting out into the PRS world maybe as a bridge, but long term, they will want to move towards a more optimized caliber for the sport. In an AR, it makes since for the obvious. Almost makes the Big Frame AR obsolete. Flatter, similar BC to the 130-140 class (assuming you run a 109, Atip or DTAC), less recoil and the biggest thing, much easier recoil management with a gasser,ect. Its making most of the other small frame boutique calibers obsolete as well. Shits all over a grendel, spc, valk ect.

When you add up all the costs then amortize across shooting, the difference in cost is minimal. The pros do not outweigh the cons IMO. Then again, less people buying up Lapua and Alpha brass I have to compete with. Hopefully they stick to their red box bullets as well. Yellow box getting too hard to find as of late.
 
I've been toying with the idea of 6 ARC for a PRS bolt gun for a bit.

Haven't pulled the trigger on either 6BR/BRA/etc yet either. The 6.5 manbun is great, but spotting hits is 'interesting' with the recoil.

M
 
I've been toying with the idea of 6 ARC for a PRS bolt gun for a bit.

Haven't pulled the trigger on either 6BR/BRA/etc yet either. The 6.5 manbun is great, but spotting hits is 'interesting' with the recoil.

M

Need to get a better brake if you can't spot shots with the Creedmoor. Recoil isn't that bad with a good brake.
 
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^^^ or maybe add some weights to your rig... 6.5CM in a 20lb+ rifle isn't bad at all.

In fact, some of the best guys in PRS (Morgun King, Andy Slade) have picked up their 6.5CMs again, shooting heavies too (153.5 and 156 Bergers).
 
Maybe for someone just starting out into the PRS world maybe as a bridge, but long term, they will want to move towards a more optimized caliber for the sport. In an AR, it makes since for the obvious. Almost makes the Big Frame AR obsolete. Flatter, similar BC to the 130-140 class (assuming you run a 109, Atip or DTAC), less recoil and the biggest thing, much easier recoil management with a gasser,ect. Its making most of the other small frame boutique calibers obsolete as well. Shits all over a grendel, spc, valk ect.

When you add up all the costs then amortize across shooting, the difference in cost is minimal. The pros do not outweigh the cons IMO. Then again, less people buying up Lapua and Alpha brass I have to compete with. Hopefully they stick to their red box bullets as well. Yellow box getting too hard to find as of late.

I don't think many people are buying 6ARC bolt guns expecting to seriously (if at all) compete in PRS.

They are just a heck of a lot of fun.
 
Yea 6 arc is absolutely compeititve with the other 6mm's. It may not have as much ass and may need higher pressures to get the same velocity, but its not going to hold anyone back. I still think the Dashers and BRs and GTs are a better choice in a vaccum, but a 109 berger at 2800 is a 109 berger at 2800.

Once i get through this 6.5grendel ammo I have, going to rebarrel the Larue into a 6 ARC. Nothing really comes closes in the small frame AR IMO.