With the release of the 6MM ARC, it seems that 6mm AR chambered barrels are about as rare as hens teeth. I built a 6mm AR using an X-caliber barrel a few years ago that performs really well. But like many other barrel makers, they no longer offer 6mm AR as a chamber option. Is there anyone making/chambering a quality 6mm AR barrel? I'd like to build another 6mm AR. Thx!
- Thread starter cbcanderson
- Start date
I’m in the same boat. Have a similar post going on this. I built a 22 grendel with a 6.5 twist barrel to shoot the bigger bullets, but accuracy was so inconsistent. Looking to simply rebbarrel to a 6mm. Everything has gone to the ARC, but why give up the velocity for no reason. I’m looking at the 6 grinch that Craddock is offering.
McGowen had it last time I looked. They might call it 243 LBC or something though.
Thanks! I checked them out and they do offer 6mm AR -- listed as 6mm Grendel
I'll give them a call and see what they say. I called X-caliber and they said their reamer was worn out. I asked them if I bought a reamer and sent it to them if they'd cut a chamber in one of their barrels. The sales guy said their shop foreman wouldn't go for it. Too bad, I love the 6mm AR
Man, I couldn't agree more. the 6mm AR has been a great performer for me out to 1,000 yards. It really sucks that Hornady gave up the case capacity in the ARC. I think the 6 Grinch from Craddock is really interesting -- I have Craddock uppers in 224 Valkyrie and another in 6mm Creedmoor (both Bartlein barrels) and they are shooters.
Not really though. I've been watching 6ARC velocities pretty closely since it arrived and they're pretty much identical to regular 6mm Grendel.
I've seen people make that point, and you may be right. I just worry that losing two grains of capacity will impact velocity. I reload, so I figured I might as well stay with the slightly larger case -- and I like using resized 6.5 Grendel Lapua brass.
6arc is just the official version of 6g so it's a toss up, just like ballistic advantage barrels who happen to have 6arc barrels in stock and 20% off. Their CS is top notch, but do your testing a lot of shit makes it out from what I've seen online.
Don't mean to hijack the thread but reading it made me to want to ask a question in my mind for a few months already. As a reloader, is 6ARC a finicky round to develop accuracy loads?
6 ARC is a good cartridge. The problem with where Hornaday landed on the final cartridge specs is that you are giving up almost 2 grains of case capacity (34 grain H20 vs. 36) when they pulled the shoulder back 30/1000ths of an inch. I know it doesn't seem like much, but I get from 2,710 FPS (accuracy load) to to 2,750 FPS (max velocity load out of my barrel before I start to see pressure signs) with my 6mm AR loads. I'd like to keep that velocity so hoping to stay with 6mm AR (Grendel) vs. switching to 6 ARM. I also like that I have access to 6.5 Grendel Lapua brass that I can easily neck-size as a source of high quality brass. Anyway, I'm just rambling at this point, but I like 6mm AR because it is a really easy wildcat to load for and I'm just looking for a really good next barrel. Current barrel was easy to find a load that would shoot very accurately, and I think the 6mm AR cartridge (and its cousins Turbo and Grinch) is the sweet spot for long-distance performance out of an AR15 rig.
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6mm AR was really easy to reload-- not finicky at all in finding good loads and the accuracy nodes seem pretty wide. I'd assume 6mm ARC would be about the same. The SD and Extreme Spread were low compared to other AR15 cartridges I load (don't ask about my experience with the 224 Valkyrie she-devil - that was the definition of finicky). RL15 and Berger 105 Hybrids were the ticket for me, although I've read some reloaders suggesting 85-90 grain bullets may be a better way to go for the 6mm ARC.
The 6mm ARC is a 243LBC with the shoulder pushed back .029". The guys at Hornady purchased one of my 6mm Predator barrels while they were making 50 sets of dies for me. They tested my 6mm Predator which is the same as a 243 LBC then shortened the case so they could load their 105gr bullet. If you load to the same pressure the 6mmARC is 50-100fps slower depending on the powder used.
Hornady's marketing ploy. No mention of Robert Whitley, who came up with the 6AR, 6ARTurboImp. What is it, a .032 headspace difference 6AR vs 6ARC ?
About 2009, I ran a 6ARTI 30" 8T Hart +2" gas location, .093 port for OTC. Fireformed 6.5 Grendel Lapua cases, 28.5 to 29.5 H4895, BR4's. A bit of tuning required- buffer (H2) and carbine spring on car tube (CSS butt assy). No Problems. Gas port locations and size info available at CLE, White Oak and others. EZ.
If I was to do it today, I would go 6ARC. Not much vel. gain w/ TI. And no fire forming!
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