6mm ARC

[ormandj]

Looks about right to me, I've had extraordinary accuracy out of both my 10.5" and 18" 6ARCs.

 

[SCL]

Gas gun. AR platform- not bolt. I have alway had better luck with bolt accuracy, so I was a little taken back.. Hornday not Hornaday. Sorry.
Factory ammo 2 bucks a pop. Be so glad when the brass finally makes its way to shelves.
Problem with Grendel resize- case volume is slightly higher- and could make me have to reconfigure a load.

 

[ormandj]

Gas gun. AR platform- not bolt. I have alway had better luck with bolt accuracy, so I was a little taken back.. Hornday not Hornaday. Sorry.
Factory ammo 2 bucks a pop. Be so glad when the brass finally makes its way to shelves.
Problem with Grendel resize- case volume is slightly higher- and could make me have to reconfigure a load.

Both of mine are gas guns. I trued the face of the uppers, shimmed the barrel extension for a heat-fit, etc - but gas guns nonetheless. Here's the 10.5" setup for prone for 800yd steel:

 

[SCL]

Wow- well according to Hornday- they saw great results from all barrel lengths with the ARC. But.....that is really a short one!

 

[SCL]

Can't find brass for the ARC. Can't even find Grendel to resize. Don't really want to go that route either. I guess I got lucky. Bought some Hornaday 103gr Black Hill. Shot 6 singles and cleaned between shots for new 24" 1/7 twist.
I reloaded those- just went off Hornady suggested load with Varget. Middle of the road 25.6 and 26- 3 each.
1st target factory, 2nd 25.6 and 3rd 26.0. All at 2.245 OAL.
100 yrds with 15+ mph wind coming from target towards me.

Guessing got lucky.

Should add- bullets where 108gr Hornday ELDM.

 

[JimSC]

going to follow this thread. I am putting together a new ARC, the old one got converted to a 6.5 Grendel. Now I am waiting on a barrel being made by Precision Firearms. My last ARC used a bottom tier barrel and averaged 1.0 - 1.5 MOA at 100 and I just was not happy with it. Anyway I am looking forward to more range reports.

 

[Ray123]

I like the 6 mm arc cartridge in sn AR, but the 6.5 grendel bolt is really thin...don't push it anywhere near bolt gun speeds. The first upper I bought wouldn't shoot into 2" 5 shot groups with match ammo...but it was the only game in town. No components, no barrels. The new 6mm ARC with no way to make one. Finally got a 18" Proof Research SS barrel, it shot so well I bought another. Side by side same day I fired the factory Areo upper against the home assembled Proof. Same match ammo...the proof 5 shots into 1/2" the Areo, 5 shots into 2.5". I made 1250 pcs of brass ...none are stamped 6mm ARC. They are all Starline 6.5 Grendel or Starline 6.5 Basic straight wall brass with no head stamp. Even made one out of a 308 case by turning the heads down and re machining the extractor groove in the brass...just in case, the need arises. I check the AR reciever face for TIR in the lathe and clean up if necessary. Use loctite high temperature sleeve retainer on the barrel extension. Use lathe and mill with indexing fixture and dial indicator to add buttons to center bolt carrier in the bolt raceway.
Add a nice aftermarket trigger and adjustable gas black. With Areo Precision ME4 Enhanced reciever and handguards, barrel nut 58 to 60 ft/ lbs...and the stainless steel 7 and 1/2 twist Proof Research barrel. Both Proof AR shoot 5 shot 1/2" groups. Sometimes in the high
.2s and .3s. Leverevolution and 108 ELD-M are very accurate and less expensive. I use the heavy bullets 107 to 115 DTAC.
But my favorites are 108 ELD-M, 108 Berger, 110 Sierra MK, 107 SMK.

 

[SCL]

I was stuck on Varget- some decent loads, but inconsistent- good one range trip, then not the next.
I started loading CFE223 and seems to be very promising.
I have an Aero/Ballistic Adv 24" 1/7 twist.
Found CFE223- 28.3, 107 SMK HPBT, 2.245 OAL, Hornday 6mm arc or resized Grendel to do very well @ 100 yrds (center group). The Hornday 108 ELDM (left group) same load specs - decent
I also loaded 105 match Horndays-group on very right (I didn't label it). The 28.3 is the starting point of 2500 fps which I believe my barrel likes.

 

[ncwg2boatguy]

Looks about right to me, I've had extraordinary accuracy out of both my 10.5" and 18" 6ARCs.

What kind of performance are you getting out of the 10.5 6ARC? What bullet? Figured you'd go lighter to increase MV.

 

[ncwg2boatguy]

Both of mine are gas guns. I trued the face of the uppers, shimmed the barrel extension for a heat-fit, etc - but gas guns nonetheless. Here's the 10.5" setup for prone for 800yd steel:

View attachment 1314801

That is outstanding truck gun. Or for pack N Go rig. Tree Stand. Jesus! And a 4k ZC scope