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June 29th, 2021

6mm ARC Cartridge Featured on Shooting USA Tomorrow

6mm ARC brownells bolts cartridge loaded ammunition hornady

Hornady’s 6mm ARC cartridge will be featured on tomorrow’s Shooting USA broadcast. Optimized for the AR-15 platform, the 6mm ARC (Advanced Rifle Cartridge) was developed in response to a request from the Department of Defense, according to Hornady Marketing Director, Neil Davies: “The DOD guys wanted a platform built that would give them all of the advantages of the .308 [7.62×51] and try to get rid of some of the disadvantages, [such as the heavier] weight of the entire system. So they went from an AR-10 system to an AR-15 system. But they also wanted to engage targets, not just across the street or inside a room, but maybe across a valley.”

SHOW TIMES: This Shooting USA Episode airs Wednesday, June 30, 2021 at 9:00 PM Eastern and Pacific; 8:00 PM Central. If you miss the regular broadcast, you can stream the show at any time on Vimeo for $0.99 per episode.

In June 2020, Hornady introduced the 6mm ARC, a new SAAMI cartridge optimized for AR-platform rifles*. The new 6mm ARC is basically a 6.5 Grendel necked down to 6mm, with the shoulder moved back around .030″. That pushed-back shoulder does reduce case capacity (and velocity), but we assume Hornady did that to create a shorter, proprietary chamber so people could not simply neck-down Lapua 6.5 Grendel brass, as has been done for years with Robert Whitley’s outstanding 6mm AR wildcat.

CLICK Image for official SAAMI Specifications:
6mm ARC brownells bolts cartridge loaded ammunition hornady

If you are intrigued by the 6mm ARC, you’ll find the products you need at Brownells — uppers, barrels, bolts, and magazines. Brownells also sells Hornady-made 6mm ARC factory-loaded ammo, but most varieties are out-of-stock right now, as is the 6mm ARC brass. More brass and ammo should arrive soon. Midsouth is also taking brass/ammo backorders. For general information, see 6mm ARC Info Page.

What Is the 6mm ARC Cartridge?
6mm ARC brownells bolts cartridge loaded ammunition hornadyThe 6mm ARC cartridge is a new SAAMI-spec cartridge based on the 6.5 Grendel case necked down for 6mm bullets, with the shoulder moved back 0.030. Yes it is designed to run in AR15-platform rifles. You’ll need a new barrel, bolt, and mags. If you already have an AR chambered in 6.5 Grendel, the ONLY thing you need to change is the barrel. Everything else — bolt, magazines, gas system – is compatible with 6mm ARC.

▶ Official SAAMI Cartridge (not wildcat)
▶ Fits standard AR15-platform rifles
▶ Fits Short/Mini action bolt rifles
▶ Efficient short, fat case design
▶ 30-degree case shoulder

For more INFO, see 6mm ARC Info Page.

What Do I Need To Shoot the 6mm ARC?
Faxon and Ballistic Advantage are already producing barrels, with more manufacturers sure to follow. All the other required components are already on the market for 6.5 Grendel rifles. Aero Precision already offers complete 6mm ARC uppers.

Permalink - Videos, Bullets, Brass, Ammo, Gear Review 1 Comment »
January 22nd, 2021

Final Day of Brownells NOT-Show with Prize Giveaway

Brownells 2021 not-show SHOT show product preview giveaway sale

There is no SHOT Show in Las Vegas this year, but in its stead Brownells is presenting a NOT-Show featuring products from major manufacturers. In addition, on every day from January 18 through 22, 2021, Brownells has offered a PRIZE Giveaway.

Brownells 2021 not-show SHOT show product preview giveaway sale

Brownells 2021 not-show SHOT show product preview giveaway sale

Brownells 2021 not-show SHOT show product preview giveaway saleToday, the final day of Brownells NOT-Show, Brownells features Stag Arms products. Along with .223 Rem ARs, Stag Arms offers AR-platform rifles in 6.5 Creedmoor (Stag 10 Marksman) and 6mm ARC (Stag 15 Covenant). Stag is one of the first manufacturers to offer complete 6mm ARC rifles.

In addition, Brownells’ tech team looks at the impressive new Area 419 Zero Turret Press (photo right). This press sets new standards for precision repeatability in a turret press.

A major unveiling today was the all-new, illuminated 1-8x24mm Match Precision Optic (MPO) from Brownells. This could become very popular with hunters because this compact scope offers a true 1-power for wide field of view, plus max 8 power to spot details at long range. This Japanese-made optic is on sale today for $799.99 complete with cantilevered AR mounting bracket.

Brownells 2021 not-show SHOT show product preview giveaway sale

On Thursday, January 21, 2021 the Brownells NOT-Show covered Hornady’s new line of RFID safes. These offer some very sophisticated features with fast-open technology.

Brownells 2021 not-show SHOT show product preview giveaway sale

Brownells 2021 not-show SHOT show product preview giveaway sale

Permalink Gear Review, New Product, News, Optics No Comments »
July 23rd, 2020

6mm ARC Cartridge — SAAMI Specs, Build Requirements, Videos

6mm ARC brownells bolts cartridge loaded ammunition hornady

In June 2020, Hornady introduced the 6mm ARC, a new SAAMI cartridge optimized for AR-platform rifles*. The new 6mm ARC is basically a 6.5 Grendel necked down to 6mm, with the shoulder moved back around .030″. That pushed-back shoulder does reduce case capacity (and velocity), but we assume Hornady did that to create a shorter, proprietary chamber so people could not simply neck-down Lapua 6.5 Grendel brass, as has been done for years with Robert Whitley’s outstanding 6mm AR wildcat.

CLICK Image for official SAAMI Specifications:
6mm ARC brownells bolts cartridge loaded ammunition hornady

If you are intrigued by the 6mm ARC, you’ll find the products you need at Brownells — uppers, barrels, bolts, and magazines. Brownells also sells Hornady-made 6mm ARC factory-loaded ammo, but most varieties are out-of-stock right now, as is the 6mm ARC brass. More brass and ammo should arrive soon. Midsouth is also taking brass/ammo backorders. For general information, see 6mm ARC Info Page.

What Is the 6mm ARC Cartridge?
6mm ARC brownells bolts cartridge loaded ammunition hornadyThe 6mm ARC cartridge is a new SAAMI-spec cartridge based on the 6.5 Grendel case necked down for 6mm bullets, with the shoulder moved back 0.030. Yes it is designed to run in AR15-platform rifles. You’ll need a new barrel, bolt, and mags. If you already have an AR chambered in 6.5 Grendel, the ONLY thing you need to change is the barrel. Everything else — bolt, magazines, gas system – is compatible with 6mm ARC.

▶ Official SAAMI Cartridge (not wildcat)
▶ Fits standard AR15-platform rifles
▶ Fits Short/Mini action bolt rifles
▶ Efficient short, fat case design
▶ 30-degree case shoulder

For more INFO, see 6mm ARC Info Page.

What Do I Need To Shoot the 6mm ARC?
Faxon and Ballistic Advantage are already producing barrels, with more manufacturers sure to follow. All the other required components are already on the market for 6.5 Grendel rifles. Aero Precision already offers complete 6mm ARC uppers.

If you’re converting a standard 5.56×45 mm (.223 Rem) AR15 upper to shoot 6mm ARC, you’ll need a 6mm barrel, a Type II 6.5 Grendel bolt carrier group, and new magazines. Some folks have suggested standard AR mags will work, but trust us, you want the magazines that have been designed for 6.5 Grendel. All the hardware you need is currently available at Brownells. And Brownells also sells complete Aero Precision 6mm ARC Uppers, starting at $749.99.

6mm ARC brownells bolts cartridge loaded ammunition hornady

6mm ARC Videos from Hornady (18 Total)

6mm ARC: Overview
6mm ARC: Handloading
6mm ARC Initial Offerings
6mm ARC: AR-15 vs AR-10
6mm ARC vs. 6.5 Grendel
6mm ARC vs the Creedmoors
6mm ARC: 6.5 Creedmoor of the Gas Gun World
6mm ARC vs 308 WIN
6mm ARC: How it started

6mm ARC: What is it
6mm ARC: Military Application
6mm ARC vs. 6.8 SPC
6mm ARC: Bolt Gun Application
6mm ARC: Cartridge Design
6mm ARC: Best AR-15 Cartridge
6mm ARC: Hunting
6mm ARC: Match
6mm ARC: Barrel Length


* While 6-6.5 Grendel shooters are known to run stout pressures, the new 6mm ARC cartridge has a relatively moderate Maximum Average Pressure (MAP) rating of 52,000 psi according to the official SAAMI specifications. For a variety of reasons, is wise to keep pressures in a semi-auto rifle moderate. Don’t chase the velocities you might get in a bolt-action gun.

Permalink Bullets, Brass, Ammo, Gear Review, Gunsmithing, New Product, News 9 Comments »
June 5th, 2020

Hornady Offers New 6mm ARC Cartridge for AR15 Platform

6mmar 6mmar turbo robert whitley

A decade-and-a-half ago, our friend Robert Whitley created the 6mmAR, a wildcat based on the 6.5 Grendel necked down to 6mm. The great thing about the 6mmAR cartridge is that is offers superb accuracy with high-BC 6mm bullets, while working in AR15-platform rifles. The 6mmAR feeds and functions using 6.8 SPC or 6.5 Grendel AR magazines. We provided a full report on the 6mmAR way back in 2006.

Hornady Introduces the 6mm ARC Cartridge for AR15 Platform
Now Hornady, with no apparent credit to Whitley’s 6mmAR, has announced a copycat cartridge, which it calls the 6mm ARC (Advanced Rifle Cartridge). Hornady will offer loaded 6mm ARC ammunition and also cartridge brass. In addition Hornady will produce reloading dies, shell plates, modified case, and other accessories. SEE 6mm ARC SAAMI Specification.

Hornady states: “Hornady® is proud to introduce the new 6mm ARC (Advanced Rifle Cartridge). Recently tested, selected and fielded by a specialized group within the U.S. Department of Defense for its multipurpose combat rifle program, the 6mm ARC is a truly versatile cartridge that maximizes the potential of the AR-15 platform.” Hornady Ballistician Jayden Quinlan adds: “We subsequently modeled and tested a variety of designs in different calibers until we were able to produce the most flexible cartridge possible within the limits of the AR-15 system. The 6mm ARC does much of what larger cartridges can and everything that smaller cartridges can’t.”

NOTE: The rim diameter (0.441) and thickness of the 6mm ARC appear to be identical to the 6.5 Grendel as illustrated on page 40 of the SAAMI Industry Standards. From all we can tell, in other dimensions as well, this is a very close copy of Robert Whitley’s 6mmAR, a 6-6.5 Grendel wildcat. For example, 6mm ARC case length is 1.49″ vs. 1.51″ for 6mmAR. The Guns&Ammo report on the 6mm ARC states: “The 6mm ARC is based on the 6.5 Grendel. Hornady started by necking down the cartridge to 6mm and then pulled the shoulder back closer to the case head .030-inch. … Hornady also set maximum chamber pressure low at 52,000 pounds PSI. This slows extraction and makes it much less violent, prolonging the bolt’s life.”

There is an extensive discussion of the 6mm ARC on the Gun University website. You’ll find dimensions and performance numbers for the new cartridge along with videos showing the 6mm ARC cartridge tested in a Barrett AR-type REC7 DI rifle. Read Gun University Story HERE.

More Velocity Than a .223 Rem, Less Weight and Recoil Than a .308 Win
Hornady says the 6mm ARC “delivers substantially better ballistics than the [.223 Rem] and offers a much lighter gun/ammo system with 30% less weight than the AR-10/308 Win system. This new cartridge delivers less felt recoil than larger short-action-based cartridges, yet takes full advantage of modern, heavy-for-caliber 6mm bullets that provide excellent accuracy and ballistic performance at extended range.”

You can see a ballistic comparison between 6mm ARC, .223 Remington, and .308 Winchester in this Hornady chart:

6mmar 6mmar turbo robert whitley

Notably, a large number of AR gun-makers have committed to producing rifles or uppers chambered for the 6mm ARC. Some of these are: Adams Arms, Barrett, Brownells, Christensen Arms, GAP, Howa, Mossberg, Noveske, Odin Works, Radical Firearms, and Wilson Combat. In addition Geissele and CMC Triggers are listed as suppliers on Hornady’s 6mm ARC webpage.

6mmar 6mmar turbo robert whitley

6mmar 6mmar turbo robert whitley

The Proven Lapua Brass Alternative — 6mmAR and 6mmAR Turbo

If you want 6mm ARC performance in your AR15 with superior case life and consistency, consider doing the 6mmAR or 6mmAR Turbo instead. These are proven designs with winning records in high power competition. Redding produces dies, and complete uppers (with proper Grendel-sized bolt face) are available from 6mmAR.com.

6mmar 6mmar turbo robert whitley

Superior Accuracy with Impressive Ballistics
Robert explained to us: “Lapua’s Grendel brass is of exceptional quality, very hard at the back, with a well-annealed neck area, and it has a small primer pocket and small flash hole. When you start with this kind of brass, you have all the ingredients of great accuracy. Necked down to 6mm, it is like a long-bodied 6 PPC, that feeds and shoots well out of an AR-15. This gives you a case that can handle high pressures, with the accuracy pedigree of the 6PPC. It doesn’t get much better than that.”

6mmar 6mmar turbo robert whitley

To create the 6mmAR simply neck-down parent Lapua 6.5 Grendel brass, which has small primer pocket and small flash hole. Case capacity is 36.0 grains of water, filled to over-flowing. (For comparison the 6mm PPC holds about 32.5 grains). To prepare cases, simply run the 6.5 Grendel brass through a Redding 6mmAR full-length sizing die. The FL die’s internal neck diameter (0.267″) is spec’d to deliver about .004″ tension on the bullet–just right for a gas gun. Redding’s 6mmAR dies were built to Whitley’s specs and closely match the actual dimensions of the Lapua brass. This video from Robert Whitley shows how to form 6mmAR cases from Lapua 6.5 Grendel brass.

Velocities: With the recommended medium-burn-rate powders, bullets in the 85- to 90-grain range can be pushed to the 2800 to 2850 fps range. In most 6mmAR rifles, the 105- to 107-grain bullets can be driven to velocities of 2700 to 2750 fps in a 24″ or longer barrel. More speed is possible, but don’t count on it with the average barrel. If you want more speed the 6mmAR Turbo offers additional case capacity. This allows the 6mmAR Turbo to drive the heavier 6mm bullets at velocities close to 6mmBR Norma cartridge levels.

Magazines: The correct magazines are the key to a reliable, competition-worthy system. For best results with the 6mmAR or 6mmAR Turbo, use special 6.8 SPC mags or Alexander Arms Grendel mags. Those specialized mags will provide better reliability than standard .223 Rem/5.56 mags for the AR15.

Permalink - Videos, Bullets, Brass, Ammo, Competition, New Product, News 14 Comments »
June 5th, 2020

Barrett Delivers New 6mm ARC Rifles to U.S. Dept. of Defense

Barrett 6mm ARC REC7 DI rifle

In a preceding story, we revealed the 6mm ARC cartridge from Hornady. This is VERY similar to the 6mmAR cartridge based on the 6.5 Grendel, which was developed by Robert Whitley a decade and a half ago. Hornady developed the 6mm ARC is cooperation with the U.S. Department of Defense (DOD), and now the first run of 6mm ARC black rifles is heading to DOD testers. Barrett Firearms Manufacturing, Inc. (“Barrett”) has announced that it has partnered with Hornady to chamber the REC7 rifle series in the new 6mm ARC offering. The first production run of these rifles has been delivered to the U.S. DOD, fulfilling a contract that was awarded to Barrett late last year. READ MORE HERE.

Barrett states: “The combination of the proven REC7 DI gas system and the potent 6mm ARC cartridge creates a product that is consistently accurate and easy to shoot. Carrying 24 rounds in the magazine, the 108 gr. ELD Match bullets leave the 18″ Proof Research match grade stainless steel or carbon fiber barrel at over 2630 fps. This easily gives the rifle supersonic capabilities past 1000 yards.”

In this video Ryan Cleckner (Former U.S. Army Ranger) tests the Barrett REC7 chambered in 6mm ARC:

CLICK HERE for 6mm ARC Cartridge SAAMI Specification »

Barrett anticipates these rifles will be available to the US commercial market after all U.S. Military deliveries have been completed.

Barrett 6mm ARC REC7 DI rifle

Permalink Bullets, Brass, Ammo, New Product, Tactical 2 Comments »