10-4, YW
6mm arc bolt gun?
- Thread starter GSRswapandslow
- Start date
A few pics of my Uintah UP-15.
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That’s a nice looking rig, dig that bolt action.
TYVM. . Have higher scopemount rings, NF's 1-3/8"ers, coming.
Some new pics.. Received the NightForce Extra-high (1-3/8") scope mounts and then removed the adjustable cheekpiece to get the scope up and my face down so that my eye is centered on the scope's exitpupil; that all works quite well now.. Scope is still the Zeiss Conquest V6 5-30X56X30.. Have changed the grip to some aftermarket one that feels better.. Am again breaking-in and developing loads after spending LOTS of time on my Big6 BR rifle.. Have sold all brass other than Lapua .220 Russian, which, of course, must be necked up (to 25-cal.), then resized overall, and then fireformed.. I use the latter loads for barrel break-in.
PS. I had installed the grip temporarily, without the safety spring and detent pin, for these pics.. That's why the safety is rotated randomly.
PS. I had installed the grip temporarily, without the safety spring and detent pin, for these pics.. That's why the safety is rotated randomly.
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I have a unitah precision AR bolt action upper in 6mm arc if interested please respond or text 267 205 4423
Took my Savage 10 GRS 6.5 Creedmoor and Made into a 6mm ARC.
24" Shaw 1-7.0 Twist, 5R Barrel. PTG PPC Bolt Face. Using MDT Metal Mag SA-12 Round 6BR Magazine. The 224 Valk Magazines will also work. AAC SDN-6 Suppressor with a AREA-419 Hellfire mounting system. Load Development: 90gr Lapua Secenar-L, 103 ELD-X, 105gr Lapua OTM Secenar, 108gr ELD-M and 110 A-Tips.
24" Shaw 1-7.0 Twist, 5R Barrel. PTG PPC Bolt Face. Using MDT Metal Mag SA-12 Round 6BR Magazine. The 224 Valk Magazines will also work. AAC SDN-6 Suppressor with a AREA-419 Hellfire mounting system. Load Development: 90gr Lapua Secenar-L, 103 ELD-X, 105gr Lapua OTM Secenar, 108gr ELD-M and 110 A-Tips.
LVLAaron
Gold $$ Contributor
6arc doesn't make a ton of sense in an AR15.
Personally, I'd rather shoot an 80g 223 that has better ballistics... or a hot 77g if you want mag length.
I dont see the advantage to 6arc in any platform.
Personally, I'd rather shoot an 80g 223 that has better ballistics... or a hot 77g if you want mag length.
I dont see the advantage to 6arc in any platform.
I don't see how any 80gn 223 combination can provide better ballistics than a small six such as the ARC using very high BC 0.243" 105-108gn bullets. I agree that for shorter distance shooters, 223 is usually more than good enough and is ideally suited to the AR platform.
The White Oak Armaments commentary you provide a link to, doesn't challenge the ballistics, but raises concerns quite rightly about over-loading the ARC and/or any Grendel / 7.62X39mm case based design with their 0.440" dia. heads in this platform. Even there White Oaks notes that there shouldn't be wear and reliability problems if ARC loads are restricted to the SAAMI/Hornady 52,000 psi MAP limit in AR-15s.
"Hornady confirmed by my feelings by limiting the new cartridge to 52,000 PSI max pressure. At that pressure bolts and barrel extensions should last a long time. [my italics] Start tipping the powder can and all bets are off. If you are one to add powder until primers fall out then back off slightly, don’t expect to keep all the lugs on your bolt if you shoot a lot."
This is academic to me (in the UK) as we cannot have gas-operated semi-autos and although AR-15 type range rifles are common, they are all manual 'straight-pulls'. (A 'quarter-auto' variation on the theme that uses gas power to push the bolt back and extract the fired case with a thumb-lever or a twin trigger pull system to release the bolt and chamber the next round has just been reclassified to Section 5 'Prohibited Weapons' status and existing models have to be handed in to police firearms licensing units.) Nobody (well, very few) AR straight-pull owners here will adopt the ARC as we found years ago that the similar cased Grendel shot well but gave very hard bolt-opening / extraction at pressures even below 50,000 psi requiring such soft loads that there was no ballistics benefit over 223. So, Grendel adoption (and the ARC if it catches on) here has been near 100% in bolt-guns. I have a Howa Mini in 6.5G and will likely give the 6-ARC a whirl in due course in a suitable small-action bolt-action rifle.
A 6MM ARC in the AR platform has a significant practical general application. The cartridge and rifle combination has ballistic improvements for rapid fire close quarter work as well as enhanced longer range work. This creates a single rifle that can be a utility rifle for the user.6arc doesn't make a ton of sense in an AR15.
Personally, I'd rather shoot an 80g 223 that has better ballistics... or a hot 77g if you want mag length.
I dont see the advantage to 6arc in any platform.
For a dedicated reloader the 6MM ARC in an AR15 has very little wiggle room between lower pressure loads that function and proper 52,000 PSI loads that allow short burst rapid fire without eroding the throat.
Self loading close quarter rifles started in 1941 with the M1, M2, 30 Carbines. From my experience in practical situations the 110 grain projectile launched in a 5lb platform has handling issues. The cartridge while having good close quarter energy has limited range, beyond 200 yards remaining energy is insufficient.
The AR15, M16 in 5.56 NATO especially in the shorter barreled M4 versions while doing well up close they suffer range, accuracy and energy limitations.
My 20" barreled AR15 A2 with 68 grain projectiles in a Delta configuration shoots 1 3/4" groups at 300 yards, however it has a practical range limitation, on low wind conditions between 500 to 600 yards, on windy days that can be reduced to 400 to 500 yards. I know you hear about the sectional density and ballistic coefficients of heavy projectiles in a 5.56 but in my experience in the practical world where target ranges vary the reduced velocity and longer time of flight in a 52,000 PSI platform are counter productive in real world practical use where target acquisition and firing needs to be very quick.
My AR15 in 6MM ARC without force multipliers weighs it at a tad over 8lbs. Shorts burst rapid fire with 105 of 108 grain projectiles has greatly improved handling over my two M1 30 Carbines. In close and extended ranges energy and accuracy is greatly improved. Longer range accuracy is improved in weather when compared to my AR 15 in 5.56 NATO. My 30 Carbines launch a 110 grain projectile at 2050 FPS, 6MM ARC is a bit over 2,600 FPS with a 108 grain projectile.
If you're talking range work I get, it the AR15 in 6MM ARC is not the cats meow, however if you want a self loading rifle combination that can handle up close and personal work, take game from in close Elk, black bear and deer you can do far worse then an AR15 in 6MM ARC. The AR is reliable, weather resistant and accurate, the 6MM ARC cartridge provides a multi use utility that the AR platform had been lacking.
Certainly my favorite 6MM varmint combination in my 700 Remington in 6MM Remington a 75 grain pill at 65,000 PSI and 3,900 FPS shoots much better at longer ranges in practical field conditions.
LVLAaron
Gold $$ Contributor
Laurie, that's fair.
My comment was short and a little snarky. Comparing an 80g SMK vs. a Hornady 108 (at safe auto loader pressures) the ballistics are close. The 80 has less drop to 1000 yards. The 108 will be .4 moa "better" in a 10mph wind @ 1000.
I guess it's more personal preference to me as I'm a bit of a purist. AR=223
My comment was short and a little snarky. Comparing an 80g SMK vs. a Hornady 108 (at safe auto loader pressures) the ballistics are close. The 80 has less drop to 1000 yards. The 108 will be .4 moa "better" in a 10mph wind @ 1000.
I guess it's more personal preference to me as I'm a bit of a purist. AR=223
I guess it's more personal preference to me as I'm a bit of a purist. AR=223
From my straight-pull AR-15 shooting days, I'd agree that the 223 is ideally suited to the rifle. A gunsmith / rifle builder friend who is a regular UK Civilian Service Rifle league competitor has become a fan of the newer 224 Valkyrie in our type of AR-15s, but I can't comment on that.
You didn't offend me. While I have nothing but respect for bench rest and target shooting, (without which many great cartridges would never have been designed) for my use I don't give as much weight to target performance as I do practical use.Laurie, that's fair.
My comment was short and a little snarky. Comparing an 80g SMK vs. a Hornady 108 (at safe auto loader pressures) the ballistics are close. The 80 has less drop to 1000 yards. The 108 will be .4 moa "better" in a 10mph wind @ 1000.
I guess it's more personal preference to me as I'm a bit of a purist. AR=223
I'm of the opinion that the AR I5/M16 in 5.56 NATO was as good as it was going to get 58 years ago. In fact it was so good that it has seen very little improvement nor much in the way of serious competition until recent developments in propellants.
Having carried the M2, the M14, the M16 and CAR15, I've been of the opinion for many years that for us civilians as well as the military the AR platform has been and will be a significant performer for many decades.
I have been waiting for a cartridge for the AR platform that covers as many of the bases between defence and general purpose usage out to 800 yards as possible for nearly 50 years.
From my experiance a quality built AR rifle has the credibility as a platform. A 6MM projectile at 2,600 FPS while a bit light for large game, in the hands of a practiced practical rifleman adequately crosses the divide from close quarters tactical to practical hunting, truck and scout rifle, as long as you stick to the 52,000 PSI limit.
My advice is if you build an AR stick with a single manufacturer for the upper and lower. The chances of it all fitting like a glove are much higher, I went with Aero Precision as a complete upper assembly was available, the lower was also Aero but I used custom fire controls.
No doubt trimming new brass will leave you with short brass. Lots of fireforming expansion going on. Learned.that the hard way long ago. Even trimming to the max will still probably leave you with short brass. Forming wildcats you just have to use trial and error. Don't trim but a few at first.
In a bolt gun for something comparable go with the 6mm grinch.
6MM GRINCH Defeats entire Field of 6PPCs
The Grinch took the 2 Gun this weekend at St Louis Missouri. Greg King piloted his 6MM Grinch for the win! Conditions were fairly light on Saturday but were a bit rougher at 200 on Sunday! It's way too early to trumpet the demise of the 6PPC, however it looks like the Grinch can hold its own...
forum.accurateshooter.com
For those that argue that their are better cartridges for the 6mm bore, Ill argue. IMHO the 6mm ARC really makes sense in the mini action bolt action like the CZ 527 Or the Howa Mini action. Guess I believe this to the point that I had a barrel spun up & chambered for a CZ 527 action. This will be a light carry rifle for deer hunting & predators. Personally feel the CZ 527 action & the 6mm ARC were made for each other.
Not sure why, though I feel the 6mm ARC may be a bit better than 6.5 Grendel for my purposes as of late.
Not sure why, though I feel the 6mm ARC may be a bit better than 6.5 Grendel for my purposes as of late.
The regular 6mmAR is the best of both worlds.
In AR platform or bolt gun..
Robert Whitley is a genius.
And Hornady stole his idea
In AR platform or bolt gun..
Robert Whitley is a genius.
And Hornady stole his idea
What kind of velocities and pressures do you expect to load for?
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