March 15th, 2020

Sunday GunDay: Twin 30 BR Score Rigs — Thunder Down-Under

30BR Hunter Class Rifle
This story, from our Gun of the Week Archives, offers a good intro to the 30 BR cartridge, which is still the leading chambering for short-range Score Benchrest.

What’s better than one custom-built 30 BR with gorgeous wood and top-shelf components? A matching pair of course. Just ask Australian shooter Greg Roche (“Caduceus” in our Forum). A decade ago, Greg spent two years living and working in the USA. While in America, he commissioned two matched custom rifles to bring back to Australia for Hunter Class BR matches. Though the look-alike rigs are both chambered in 30 BR, one is designed for the Australian “Traditional” centerfire Hunter Class (10-lb limit), while the other is purpose-built for the “Custom” centerfire Hunter Class (14-lb limit). The 10-lb Traditional rifle features a fully-functioning two-round magazine and a 6-power scope. In contrast the Custom Class rifle is a single-shot action, with a 45X Leupold scope. The Custom weighs 13.5 pounds so it can also be used in traditional Heavy Varmint Benchrest matches if desired.

30BR Hunter Class Rifle

Tale of Two Rifles
Story and Photos by Greg Roche (“Caduceus”)

The USA boasts some of the finest precision rifle-builders and Benchrest parts suppliers in the world. Before returning to Australia after two years in the States, I decided to have two special BR rifles built using American components and skilled labor. I wanted a matched pair — twin guns that would be as handsome as they were accurate. The heavier gun of the pair, the 13.5-lb Custom Class rifle, features top-of-the-line (but well-proven) technologies and components. With the 10.5-lb Traditional Class rifle, we had to develop new solutions to allow the 30 BR cartridge to feed from a functional two-round magazine. Here is my saga of how my twin 30 BRs were conceived and built, and how they have performed in competition.

30BR Hunter Class Rifle

BACKGROUND — The 30 BR for Score Competition

The 30 BR is a wildcat cartridge based on a necked-up version of the 6mmBR Norma case. It originated in U.S. Benchrest circles where it found its niche in Varmint For Score (VFS) matches. Unlike traditional Benchrest, where group size determines the winner, VFS matches are shot on a target with multiple, concentric-ringed bullseyes. Point total is based on “best edge” shot location (one shot per bull). In score competition, the 30 BR’s “supersized” .308-diameter hole offers an advantage over the 6mm hole created by a 6 PPC, the dominant group BR chambering.

30 BR cartridge

The starting point for loading the 30 BR wildcat is Lapua 6mmBR brass. These are necked up as a single-step operation using a .30 caliber tapered expander ball (or dedicated expander mandrel). This will leave a bulge in the neck, so the expanded case neck is normally turned to bring the thickness down to the correct dimension for the chamber. I turned these necks down to .010″ wall thickness using a Stiller neck-turning tool. It features an eccentric mandrel similar to the Nielson “Pumpkin”. Loaded rounds measure .328″ neck diameter. This gives minimum clearance in my .330″ neck chamber, so very little neck resizing is needed after firing. Cases are trimmed to 1.500″ prior to turning to ensure consistency since the Stiller tool indexes the length of cut off the case mouth. Other than that, cases are just chamfered, loaded and made ready to shoot. No special fire-forming is required.

17-Twist Barrels for Both Rifles
Texan gunsmith Mike Bryant chambered both barrels. Mike also polished both barrels to a high-gloss to match the receivers. In this game, barrels are consumables, much like powder and primers, so most owners wouldn’t bother to polish their barrels. However a 30 BR barrel can provide up to 5000 rounds of accurate life (unlike a 6PPC barrel which might be tossed after 800-1000 rounds.) So, these barrels are likely to be on the rifles for many seasons. Given the high-gloss finish of the Grizzly actions and the beauty of the Red Cedar stocks, it would have been an injustice to leave a dull finish on the barrels.

The chambers were both cut with the same reamer supplied by Dave Kiff of Pacific Tool and Gauge. Randy Robinett, one of the originators of the 30 BR wildcat, specified the reamer dimensions. Randy’s 118gr, 10-ogive custom BIB bullets and the 30 BR cartridge enjoy a winning track record in the USA. The 30 BR Robinette reamer has zero free-bore and a .330″ neck, and is optimized for the BIB 118s. The bullets perform best when seated far enough out to jam firmly into the rifling as the bolt is closed. The long ogive means the bullet’s bearing surface is very short.

Slow Twists for Maximum Accuracy
You may note the unusually slow twist rate of both barrels. In most .30-caliber chamberings, the barrel twist rate is 1:11 or 1:12 to stabilize 150gr to 200gr bullets. The 30 BR is optimized for 115gr to 118gr flat-base bullets and 1:17 provides sufficient stability at muzzle velocities around 2900-3000 fps. In competitive Benchrest, where every thousandth of an inch counts, over-stabilization of projectiles can hurt accuracy, so “just stable enough” is the goal; hence the 1:17 twist.

Case Forming, Case Prep, and Reloading Methods

Sinclair Neck Micrometer, 30 BR Neck Turning
A Sinclair case neck micrometer indicates neck thickness of 0.010″ after neck turning.

Sinclair Neck Micrometer, 30 BR Neck Turning30 BR dies are readily available from a number of manufacturers. I personally use Wilson neck and seating dies with a Sinclair Arbor press, but Redding and Forster both supply high-quality threaded dies for use in a conventional press. For under $100.00 US, custom full-length dies can be obtained from Hornady and CH Tool & Die by sending them reamer prints or a couple of fired cases. Harrell’s Precision offers “semi-custom” dies. Just send them some fired cases and they select a pre-made CNC-cut die that ideally fits your chamber. You can ask the Harrell brothers for a die that’s tighter at the shoulder or base, or otherwise customized to your preferences.

Load Development and Accuracy Testing
With cases formed and bullets selected, load development is simply a matter of choosing the right primer, powder and charge weight, and loading the most consistent ammunition possible. The Lapua BR cases use a small rifle primer. The choice here was Federal 205 Match primers vs. CCI BR4 Benchrest primers. Some shooters have also had success using CCI 450 Magnum primers but it is very unlikely the small case needs this much spark to light off regular extruded powders. In my case, I selected Federal primers because availability tends to be better in Australia.

The relatively large bore-to-capacity ratio of the 30 BR case means that fast burning powders are the order of the day. Once again, US experience suggests H4198 (the Hodgdon equivalent of ADI AR2207) is the choice of match winners. The fact that H4198/AR2207 is an Australian-made product is an added bonus. So, I loaded up test rounds with AR2207 from 32.5 grains to 35.0 grains in approximately 0.3 grain increments. All bullets were seated to jam +0.010″ into the lands. This places the bullet base about two-thirds of the way down the neck and well short of the neck-shoulder junction.

READ FULL Story on AccurateShooter.com Main Site »

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March 15th, 2020

Review Shooting Fundamentals with Ryan Cleckner Video

Still Tac30 action tactical rifle Ryan Cleckner book
Photo by Forum member GAT. Chambered in 6-6.5×47 Lapua, this rifle features a Stiller TAC30 action, Krieger barrel, Harrells brake, Konohawk Stock, and Sightron SIII 6-24x50mm scope.

Ryan Cleckner has created many good shooting videos for the NSSF, such as his excellent Understanding MOA Video. Ryan is noted for his ability to explain complex topics in an easy-to-comprehend manner. This video, covering the fundamentals of shooting, has been viewed over 1.6 million times. It’s worth watching, particularly for guys getting started in PRS/practical competitions.

In this video, Ryan Cleckner reviews proper technique for rifle shooters. A stable platform, sight alignment, sight picture, and trigger control are key fundamentals to shooting properly. This is basic stuff, but Cleckner presents it in a clear, logical fashion. This is a good video for novice shooters.

Tip on Viewing Your Reticle:
Cleckner: “Sometimes it can be difficult to focus between the target and the reticle, even with the parallax adjusted properly. I recommend you focus only on the reticle. Just like the front sight on a rifle or a handgun, that reticle is what you can control, and it’s what matters. Focus on a crisp, clear reticle, in a stable platform, and all that’s left is trigger control.”

Tip on Trigger Control:
Cleckner: “Trigger control is pretty straightforward, as long as you think about it as a continuous process, and not just one thing that happens. I like to think about it as drawing a line in the dirt. I like to think about this constant pressure that I’m adding as I draw this line straight back, and then… continuing to draw that line even as the rifle goes off. That’s the good follow-through you’ll need.”

Long Range Shooting Handbook — A Good Resource
Cleckner has authored a book, the Long Range Shooting Handbook, which expands on the topics covered in the above video. You can view Sample Chapters from Ryan’s Book on Amazon.com.

Ryan Cleckner’s new book is designed as an intro to important fundamental concepts such as MOA vs. Mils, External Ballistics, and Environmental Effects. Included are personal tips and advice based on Cleckner’s years of experience as a sniper instructor and special operations sniper.

The Long Range Shooting Handbook is divided into three main categories: What It Is/How It Works, Fundamentals, and How to Use It. “What It Is/How It Works” covers equipment, terminology, and basic principles. “Fundamentals” covers the theory of long range shooting. “How to Use It” gives practical advice on implementing what you’ve learned, so you can progress as a skilled, long range shooter.

As a long-range shooting expert, Ryan Cleckner has impressive credentials. Cleckner was a special operations sniper (1/75 RGR) with multiple combat deployments, and he has served a U.S. Army sniper instructor. Currently he works as a firearms industry executive and attorney.

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March 15th, 2020

Accurate Cartridges — The .284 Shehane, an Improved .284 Win

F-Class Reloading .284 Winchester Win Shehane Accuracy

If you look at that 5-round group you might think it was shot with a 6 PPC or maybe a 6mmBR. But no, this was done with heavy 180gr Berger Hybrid bullets and the .284 Shehane, an improved version of the .284 Winchester. In fact, this impressive sub-quarter MOA group was shot while fire-forming with a very well-worn barrel! Gun builder Ryan Pierce of Piercision Rifles explains:

Here’s a 5-shot 0.191″ group at 100 yards with my .284 Shehane fire-forming loads. This barrel has 2200 rounds through it. It had 2000 as a straight .284 Win and then I set it back to .284 Shehane to form brass with. This was the first five rounds through it after I cleaned it after the last match. [The load was] 180 Hybrids with 54.0 grains of H4831 SC.

Ya, I figured why not I had some old barrels laying around so I just chopped 2″ off the back and 1″ off the front and chambered it up as a Shehane. Had 1000 pieces to fireform and didn’t want to do all that on a brand new barrel.

My fireform loads are going 2765 FPS. I have a 29″ barrel also though since it’s a setback. Once you get it formed I would push it faster than that or I wouldn’t even bother with the Shehane. My old straight .284 load at 2890 fps had ES spread in single digits for 10 shots. I figured if I get it up to 2935-2950 fps that will be a point or two saved in a several day match.

.284 Winchester Shehane Reamer Print PT&G

Our friend Erik Cortina notes that the .284 Shehane has a velocity edge over the straight .284 Win because it holds more powder: “The Shehane has more capacity than the .284 Winchester. Ryan is using 54.0 grains simply as a fire-forming load. Typical load for a Shehane is around 57.0 grains of Hodgdon H4831 SC.” By blowing the sidewalls out 0.010″, the .284 Shehane picks up about 3.3 grains of extra case capacity. That enhancement makes a BIG difference. The extra boiler room is enough to drive the 180s at 2900-2950 fps with H4831sc, with long barrels.

Forum member Jim Hardy has shot the .284 with great success. He tells us: “In my humble opinion, the .284 Shehane is the best balanced long-range round there is — bar none. Here is why:

You have to shoot a 30 Cal Magnum with a 240gr bullet to equal the performance of most 7mm chamberings with the 180 Berger VLD. With the .284 Shehane, you have a .308 bolt face, medium action, and Lapua brass. You use less powder than the 7 mags, and have great accuracy and ballistics even while fire-forming. The .284 Shehane shoots inside the 6.5 AND the straight .284, the .300 WSM, and the .300 Win Mag with less recoil. What is not to love about the 284 Shehane? It is a no-brainer for long range — F-Class or Prone or 1000-yard Benchrest.”

Scotland’s Grant Taylor. who used the .284 Shehane to finish third at the 2009 F-Class Worlds in England says the .284 Shehane is “very accurate with superb vertical spreads at 1000 yards. [This] caliber… has awesome accuracy. I’m getting 2930-2950 fps with spreads in the 3-5 fps range. I use Hodgdon H4831sc powder, CCI BR2 primers, and pointed 180gr Bergers.”

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