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February 23rd, 2025
Chuck’s Pair of Pennsylvania Dashers
The 6mm Dasher wildcat cartridge is very popular among competitive benchrest shooters, varminters, and even PRS competitors. So this Sunday we thought we’d showcase a matched Duo of Dasher rifles belonging to a Forum member Chuck L. (aka “Ridgeway”). The 6mm Dasher began as a wildcat improved version of the 6mmBR Norma cartridge. The Dasher has been very successful in competition, and now factory Peterson 6mm Dasher brass is sold by Grafs.com. And Alpha Munitions also offers high-quality 6mm Dasher cartridge brass.
Chuck has a prize pair of 6mm Dashers for competitive benchrest and varmint matches in Pennsylvania. Both guns feature Kelbly Panda RBLP actions, Bartlein 8-twist barrels, and Shehane Laminated Tracker Stocks. However, the two rifles are not exact twins, as you can see. One, which we’ll call the Big Dasher, is built on a Shehane ST1000 Tracker stock. The other gun, the Small Dasher, sports Shehane’s “Baby Tracker” stock — a design used with great success by Richard Schatz. The Big Dasher, optimized for 1000-yard competition, has a slightly longer freebore — 0.136″ vs. 0.104″ for the Small Dasher.
| Specifications for the Dasher Duo:
Small Dasher (13.5-pounder): Chambered for 6mm Dasher with approximately .104 freebore and a .264 NK. (No way of knowing exactly since its freebore was set in a separate operation by Kelbly.) Components are: Shehane Baby Tracker laminated stock, Kelbly Panda RPLB action, Bartlein 1:8″ LV barrel at 26 ¾”, Kelbly Rings, Weaver T36, Jewell trigger. The barrel was chambered by Kelblys and the stock was bedded, glued and balanced by a shooting buddy (Forum Member johara1). Chuck clear-coated the stock with auto urethane. Total weight is 13 lbs., 4 ounces.
Big Dasher (1K Light Gun, 17-pounder): Chambered for 6mm Dasher with a .136 freebore and .264 neck (PTG Reamer). Components are: Shehane ST-1000 laminated stock, Kelbly Panda RPLB action, Bartlein 1:8″ HV 5R barrel at 28″, Shehane +20-MOA rings, Nightforce NXS 12-42x56mm, Jewell trigger. The barrel work, pillar installation, and bedding was done by Dave Bruno. The stock was clear-coated by Chuck with auto urethane. Chuck also made the rear butt plate and balanced the rifle. Total weight: 16 lbs., 13 ounces. |
Chuck tells us: “I don’t get out shooting competition as much as I want due to time and family, but when I do compete, I shoot a Groundhog match at Southfork Rifle Club in Beaverdale, PA. Info on Southfork Club events can be found at Southforkrifleclub.com. The Southfork match is basically a 100-, 300- and 500-yard match with one sighter the entire match and 5 shots at each yardage for score. The Small Dasher, with the shorter ‘Baby Tracker’ stock, was set up for the Southfork Rifle Club’s ‘Light Unlimited’ class which has a 13.5-lb max weight.” (Editor: ‘unlimited’ is a misnomer for a weight-limited category.)
Chuck adds: “The Big Dasher with the heavy ST-1000 stock is set up for 1000-yard benchrest matches in Light Gun class. I shoot 1K matches with it at Reade Range in southwest Pennsylvania. One ironic thing is, it shoots the same load I’m shooting out of the lighter gun rather well. The only difference between the two chambers is the freebore is roughly thirty thousandths longer on the 1K gun (Large Dasher). I will also shoot this at Southfork in the ‘Heavy Unlimited’ class.”
Both Dashers Group in the Ones at 100 Yards
Chuck favors 107gr Sierra MK bullets in both Dashers. Other components are: Reloder 15 powder, Lapua cases, and CCI 450 primers. His main load for the Small Dasher is 33.0 grains of Reloder 15. This load shoots in the ones at 100 yards. For the Big Dasher Chuck reported: “I’m still working on a load, although the same 33.0 grain load shoots in the ones in the heavier gun as well. I’m still looking for more velocity and my ‘max’ node.”
Dasher Brass — Four Options
1. Buy Peterson 6mm Dasher Brass
In years past, you had to create your own Dasher brass, by fire-forming (with or without projectiles), or by hydro-forming. However, Peterson Cartridge now offers quality factory-made 6mm Dasher brass. This brass is available right now at Grafs.com.
If you do not want to waste time with fire-forming or hydro-forming, you can look for Peterson 6mm Dasher brass. This is excellent quality brass that has earned high praise from purchasers. The price — $62.99 for 50 cases at Graf’s (i.e. $1.26 per case) — is less than what you’d pay for Lapua 6mmBR brass, which is $149.99 for 100 cases or $1.50 per case. The advantage is that you save time, barrel life, and you won’t lose any cases to split necks. Peterson brass can be ordered from Grafs.com.
2. Buy Alpha Munitions 6mm Dasher Brass
Another great source for ready-to-run 6mm Dasher cartridge brass is Alpha Munitions. The made-in-USA Alpha 6mm Dasher brass is long-lasting and has been very popular with Benchrest and PRS/NRL competitors. Alpha 6mm Dasher brass costs $135.00 per hundred, or $1.35 per case. Unfortunately, as of 2/23/2025, this Alpha 6mm Dasher brass is out of stock, but it should be available later this spring.
One tip — as the capacity may vary slightly from Lapua 6mmBR brass fire-formed to 6mm Dasher, you should work up your load. Also, if you are chambering a new barrel you should get a chamber reamer that is optimized for the Alpha 6mm Dasher brass dimensions. User reviews of the Alpha 6mm Dasher brass have been highly positive: “Fantastic packaging and fantastic brass! It’s pricier than some other brands but there is a reason for that. It’s a quality product worth every penny.” — Chris Vaughn.
3. Fire-Form Dasher Brass with Bullets Hard in Lands
Chuck fireforms his Dasher brass for both rifles. Because he has a tighter-neck chamber, he neck-turns the brass first: “To fireform, I turn my cases down to fit the chamber and stop where the false shoulder makes snug contact with the chamber. Fire-forming rounds are loaded up with a 29-grain charge of H4895 or Varget and a 108gr Berger bullet seated hard into the lands about 0.020″ past initial contact with the rifling. It takes about three firings to make a nice clean Dasher case with a sharp shoulder.”
Chuck anneals his Dasher brass regularly to help maintain consistency: “I anneal about every 3-4 firings. I have many cases that have about 10+ firings on them and they are still shooting well. The primer pockets are a little looser, but still hold a primer.”
4. Have Darrell Jones Hydro-Form Your 6BR Brass to 6mm Dasher
DJ’s Brass can hydro-form a wide variety of cases for a modest fee
 Fire-forming all your own 6mm Dasher brass takes time, costs money (in bullets and powder), and consumes precious barrel life. Well there IS a better solution — you can have your new brass hydro-formed by DJ’s Brass to your exact specifications for a $60.00 per hundred, which includes annealing.
DJ’s Brass Service now offers custom case hydro-forming to your exact specs. Darrell Jones offers this service for a variety of popular cartridges: 6 PPC, 30 PPC, 30 BR, 6 BRA (BR Ackley), 6mm Grinch, 6 BRDX, 6 BRX, .260 Ackley, .284 Shehane and of course the very popular 6mm Dasher. After hydro-forming your brass, Darrell can also neck-up or neck-down the cases to meet your needs. He can also turn the necks to your specs for an additional $0.60 per case.
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February 16th, 2025
Spring is coming soon, and that means it’s time to get ready for early varmint season. Here are eight great rifles from our Shooters’ Forum Favorite Varmint Rifles Thread. You’ll see a variety of action types and stock designs, both custom and factory. And we’ve featured a wide range of chamberings, from 17 Fireball up to a .243 Super Rock Chucker (aka 6mm-06). The common factor is serious accuracy. All these rigs are great shooters that have brought smiles to their owners while bringing doom to varmints.
1. Rem 700 in 20-222 — with Birthday Gift Barrel from Dad
This is proof that you don’t have to spend a fortune to have a great varmint rig. Forum member JDS Holler posted: “Here’s my baby, ‘Plain Jane’. I took a $500 birthday check that my Dad gave me, and ordered a great barrel from PacNor, chambered in 20-222. I got busted up in a fall, and had four months down time to accumulate the components to add to my old .222 Rem 700 donor action. I couldn’t be happier with the outcome. That old Bushnell has been replaced by a Vortex Viper, and this rifle just flat shoots.”
2. 6 BRA with Krieger Barrel from Alex Wheeler
Alex Wheeler of Wheeler Accuracy knows a thing or two about accurate rifles, having built many match-winning benchrest rifles. For varmint work he likes the 6 BRA (BR Ackley) wildcat cartridge: “My favorite varmint setup is this 6mm rifle with BAT SV action in a Nesika bay varmint stock with a 1:8″-twist Krieger HV contour barrel chambered for 6 BRA. I like the 6mmBR and variants (Dasher, BRX, 6BRA) with zero freebores.” He gets great results with 55-60 grain Sierras and Noslers with H322 powder: “I shot 55 Sierra Blitzking, 55 Nosler Ballistic Tip, and 60gr Sierra Varminter HP. H322 was the best powder. Jam ‘em 10 thou in the rifling — and of them — and man they were like magic.” Alex also feels the 6mm rifles are easier to tune than 22-caliber varmint rigs and the 6mm barrel throats last longer. He often puts an older 6mm match barrel on a varmint gun and it still holds quarter-MOA.
Alex recommends sticking with a 1:8″-twist even when shooting light 6mm bullets. The extra RPM makes the bullets MUCH more explosive on critters: “I’ve done one 1:13.5″-twist and I’ll never do that again. I’m not kidding, with the 8-twist it’s twice as energetic. It can lift those ground squirrels 20 feet in the air. With the 13.5-twist it’s not half that.”
About the Suppressor — The rifle is wearing a “can” in the photo. However, Alex tells us that he now avoids suppressors for most varmint work: “I didn’t like the suppressor — it put off so much heat that the mirage was terrible. With the heat mirage, after 5-10 shots you couldn’t see. I learned my lesson. I pulled that sucker off after the first time I shot it.”
3. 6mm Dasher in Convertible Laminated Stock
The 6mm Dasher has won many benchest matches, and it’s also an ultra-accurate varminting cartridge. This Dasher belong to Forum member MTLager who posted: “Here’s my baby — 6 Dasher with BAT SV action. First one built. Serial number PT1.” This impressive rig features a tack-driving, 1:8″-twist Brux Heavy Varmint contour barrel. This rig is “Smokin the 75gr V-Maxs” reports MTLager. The stock is very interesting. MTLager explains: “This is a Richard Franklin laminated blank made into a stock by J.T. Barber. It has a 3″-wide fore-end for varmint shooting. But I can change the front to 4″-width and a rear section can be removed.” The angled rear “toe” of the buttstock can be taken off, allowing a flat, straight bottom for benchrest competition.
4. Slick 17 Fireball with BAT Action and Stunning Stock
This rifle is almost too pretty to carry out into the varmint fields. Look at that wood! This handsome small-caliber varminter belongs to Forum member “20 TAC”. Chambered for the 17 Fireball wildcat (.221 Fireball necked down), this rig features a BAT Action, Jewell Trigger, and a custom exhibition-grade walnut stock sporting a true ebony fore-end cap. The checkering is exceptional. Owner 20 Tac report this rig “shoots 20 grain V-Max bullets with H4198 very well.” That’s a Nightforce scope on top.
5. 6mmBR in McMillan Stock with Krieger Barrel
This website stated 17 years ago as 6mmBR.com, so we had to include a classic 6mmBR Norma in today’s varmint rifle line-up. Forum member Powderbrake posted: “Here is my favorite varmint rifle — [a 6BR with] Stiller Predator V RBLP action, bedded in a McMillan stock.” This accurate varminter features a 1:8″-twist 6mm Krieger barrel and Jewell trigger. Up top is a Nightforce NXS 8-32x56mm scope. Below are the owner’s key gear items: Leica Laser-Rangefinding Binoculars, Smartphone with Applied Ballistics software, and Kestrel Weather Meter. Powderbrake told us he recently upgraded to a Model 5700 Kestrel with ballistics software and LiNK. (Editor: The $399.00 Kestrel 5700 has ballistics software, but if you want the full Applied Ballistics suite, order the $699.00 Kestrel 5700 Elite).
6. Efficient 20 Vartarg for Prairie Dog Adventures
The .20 Vartarg is based on the .221 Fireball case, necked down to .204 and slightly modified for extra capacity. This very efficient cartridge offers low recoil and great accuracy. It’s one of our first choices for ground squirrels and P-dogs out to 300 yards. 20 Vartarg here belongs to Forum Member DogBuster, an avid varminter based in Utah. He posted: “If I recall, I had a hot spot in this location — probably kilt 150+ prairie dogs that morning. The hay wagon helped too, offering added elevation.”
7. AR-10 Custom in .243 Winchester
Forum Member Urban Rifleman calls this .243 AR10-platform rifle the “Goblin Killer”. This Gen 2 DPMS rifle features a Craddock Precision Bartlein 1:8″-twist 5R barrel chambered in .243 Winchester with a Tubb assymmetrical muzzle brake. Up front is the unique Tubb Bipod which reduces hop. The buttstock is a Magpul PRS Gen 2. The scope is a Leupold VX-3i LRP 6.5-20x50mm FFP TMR. We’re told this rig “will easily shoot 1/2 MOA, sometimes much smaller”.
Urban Rifleman produces a variety of great gun accessories sold through TheUrbanRiflemanStore.com. That green grip is his Urban Rifleman/Tubb ergonomic grip.
8. Savage 20 BR Varmint Rifle with Hart Barrel
This rifle is owned by Forum member VolDoc. The action is a Savage Dual Port, with an aftermarket Sharp Shooter Supply (SSS) 4 oz. Evolution trigger. The stock is a modified Savage factory unit that has been pillar-bedded. The factory barrel was replaced with a 28″ Hart stainless, 1:9″ twist barrel fitted with a Rayhill muzzle brake. The gun is chambered in 20 BR with a 0.235″ no-turn neck. Kevin Rayhill did the smithing. To provide enough elevation to shoot at 1,000 yards plus, Ray fitted a +20 MOA Bench Source scope base. This +20 rail is very well-crafted, and made especially for the Savage Model 12. VolDoc reports: “The mild recoil of the 20 BR, along with a very good muzzle brake (Rayhill’s design) enables me to spot every hit or miss myself. Kevin also re-contoured the underside of the Savage stock so it tracks straight back on recoil, also making seeing hits easier. My 55gr Berger load with runs about 3590 fps. Varget was very accurate with the 55s.”
| The 20 Caliber 1000-Yard Prairie Dog Quest |
 Making the 1032-Yard Shot with a 20 BR
by Dr. John S. (aka “VolDoc”)
Here’s my account of a successful quest for a 20-caliber varmint kill past 1,000 yards. This may be a first — I couldn’t find anyone else with a confirmed 20-Cal Prairie Dog kill at 1000+. Well, folks, I can tell you, hitting a Prairie Dog at 1000 yards isn’t easy — but it IS possible. Here’s how it was done….
Gale-Force Winds and High Temps
At our Prairie Dog Ranch in Colorado, I soon realized my quest was going to be especially difficult because we had 40+ mph winds and 100° heat every day. We had a special place where Birdog and I had made many 1,000-yard+ kills in years past, so I knew the ideal location but needed a small window of opportunity either early morning or late afternoon. Based on past experience, I knew I needed about 21 MOA from my 100-yard zero to get to 1,000 yards. On the first day of the Safari, I shot the 20 BR in the 45 mph brutal winds and heat of 97°. But after about 20 shots, I connected on a dog and lifted him about three feet high. Well, that’s a start.
Winds Subside — Here’s Our Chance …
On the second day of our shoot, I had listened to the early weather forecast, so I knew that there was to be a brief period of light winds early in the morning. We were out on the Colorado prairie at daylight and the conditions were perfect. The sunrise was at my back and we had about a 10 mph tailwind. I looked through my Leica Geovid Rangefinder Binos and the Prairie Dogs were out for breakfast. I quickly ranged the targets and found a group at about 1,050 yards. The technique is to find the dogs, range them, click-up according to your ballistic chart and shoot.
My first shot was very, very close. I added about four clicks up and a couple of clicks left for windage and let another go. That shot threw dirt all over, but the dog didn’t even flinch. This is another good point to remember about long-range Prairie Dog hunting. To be successful, the dogs can’t be too skittish, because if they have been shot at even a few times, they will go down and stay down. So, you should have an agreement with those in your party as to where each member is going to be shooting and respect this boundary. Drive-by shooting style is OK if that’s your thing, it’s just not mine.
 Hitting the Mark — Dead Dog at 1032 Yards
On the fourth shot, I saw the dog go belly up and kick its final throws. My quest for the 20-Caliber 1,000-yard Prairie Dog had become a reality. We confirmed the distance with our lasers at 1,032 yards. Our technique for retrieving a dead dog at that range is worth mentioning. When I killed that dog, I left it in the crosshairs of my Nightforce scope. My shooting buddy kept looking through the scope (of my gun) and guided me to the deceased dog using Motorola walkie-talkies.
When I got to the dog I was jubilant. I marked it with my tripod and orange jacket, and we took some pictures. The 55gr Bergers require a center mass hit as they will not expand, especially at that range. I centered this dog in the head — his BAD LUCK, my GOOD.
After making the 1,032-yard kill, I shot many many other Prairie Dogs with the Savage 20 BR using the 40gr V-Maxs. The dog flights were spectacular — red mist and helicopters, counter-clockwise or clockwise on demand. I killed at least five at over 500 yards. I will not use the 55 Bergers on Prairie Dogs again since the quest is over. I will use the 40gr V-Maxs and 39gr Sierra BlitzKings for next trip’s 20 BR fodder.
Parting Shot from Groundhog Country, SW Pennsylvania
This nice tripod with rifle mount (and Rem 40XB 22-250 on top) belongs to Forum Member Snert.
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February 5th, 2025
You don’t hear much about PacNor barrels in long-range competition, but FORUM member Wes J (aka P1ZombieKiller), proved that they can shoot “lights-out” in a rig assembled by a talented gunsmith. A few seasons back, Wes decided to upgrade a 6mmBR for mid-range benchrest and varmint matches. Wes tells us: “Since I restocked my 6BR … I have not had a chance to shoot it much since I have been playing the 100-200 game. I decided to take it out and do some playing at 500 yards. I have to give some serious props to my buddy (and fellow FORUM member) ‘PREACHER’ who did the chambering and barrel work for me. He can certainly make a gun shoot good. The barrel is a PacNor 1:8″ twist. My load was 105gr Berger VLDs pushed by 29.6 grains of Varget.” The five-round, 500-yard group shot by Wes J with his 6BR, measured just 1.240″, as measured by OnTarget software. Now that’s one accurate rig!
Five by Five — 5-Shot Group at 500 Yards, 1.240″, 0.237 MOA
This Editor knows something about the potential of a PacNor barrel. I have a 3-groove stainless PacNor SuperMatch on a Savage-actioned 6BR. This barrel shoots honest quarter-MOA in calm conditions, and it cleans up super-easy. The interior finish is so good, I’ve never had to brush the bore or use abrasives, and after 750 rounds it shoots as well as ever. I attribute the easy cleaning to the fact the lands in a PacNor 3-groove are wide and flat, so they are gentle on bullet jackets. I think accuracy is helped by the fact that my PacNor runs on the tight side (0.236 land dimension) with a good amount of choke. That works well with the 105gr Lapua Scenars and 103gr Spencers I like to shoot. You can read more about my rifle, nick-named the “Poor Man’s Hammer”, in this Feature Article from our archives. On one particularly calm day, in the hands of my friend (and ace trigger-puller) Joe Friedrich, the Poor Mans’ Hammer put 3 shots in under 0.200″ (measured center to center) at TWO Hundred yards. If you get a good one, PacNor three-grooves can definitely shoot.
 Target Measurement with OnTarget Software
We used OnTarget software to measure the 5-shot group in the target above. This easy-to-use software is very repeatable, once you get a feel for plotting the shots. The latest On Target v2.25 Precision Calculator is FREE for a 15-day evaluation period. If you like it (and you will, trust us) there’s a modest $11.99 registration fee to activate the program. In addition to group size (in inches), OnTarget plots distance to aiming point, and the software automatically calculates the group’s vertical height, horizontal dispersion, average to center (ATC), and group size in MOA.
You can run a measurement on a scanned target or a photo of a target. You’ll need some known reference to set the scale correctly. The target above had a one-inch grid so it was easy to set the scale. Once you’ve set the scale and selected bullet diameter and target distance, you simply position the small circles over each bullet hole and the OnTarget software calculates everything automatically, displaying the data in a data box superimposed over the target image. To learn more about OnTarget Software, read AccurateShooter.com’s OnTarget Product Review. This article covers all the basics as well as some advanced “power user” tips. NOTE: Since the review was written, On Target has updated the software, and the free version now has a time limit.
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November 15th, 2024
 The 30 BR is an amazing little cartridge. However, 30 BR shooters do have to neck-up 6mmBR or 7mmBR brass and then deal with some issues that can arise from the expansion process. One of our Forum members was concerned about the donut that can form at the new (expanded) neck-shoulder junction. Respected bullet-maker Randy Robinett offers tips on how to deal with the “dreaded donut”.
The Forum member was concerned about thinning the brass if he turned his 30 BR necks after expansion: “Everything I have found on 30 BR case-forming says to simply turn off the bulge at the base of the neck caused by the old 6BR shoulder. I expanded my first case and measured the neck at 0.329″ except on the donut, where it measures 0.335″. Looking inside the case… reveals a groove inside the case under the donut. Now, it is a fact that when I turn that neck and remove the donut, the groove is still going to be there on the inside? That means there is now a thin-spot ring at the base of the neck that is .005 thinner than the rest of the neck. Has anyone experienced a neck cracking on this ring?”
Randy Robinett, who runs BIB Bullet Co., is one of the “founding fathers” of the 30 BR who help prove and popularize the 30 BR for benchrest score shooting. Randy offers this advice on 30 BR case-forming:
While the thinner neck-base was one of our original concerns, unless one cuts too deeply INTO the shoulder, it is not a problem. For my original 30BR chamber, thirty (30) cases were used to fire 6,400 rounds through the barrel. The cases were never annealed, yet there were ZERO case failures, neck separations, or splits. The case-necks were turned for a loaded-round neck diameter of .328″, and, from the beginning, sized with a .324″ neck-bushing.
The best method for avoiding the ‘bulge’ is to fire-form prior to neck-turning (several methods are successfully employed). Cutting too deeply into the shoulder can result in case-neck separations. I have witnessed this, but, with several barrels and thousands to shots fired, have not [personally] experienced it. The last registered BR event fired using that original barrel produced a 500-27x score and a second-place finish. [That’s] not bad for 6K plus shots, at something over 200 firings per case.
Check Out the 30 BR Cartridge Guide on AccurateShooter.com
You’ll find more information on 30 BR Case-forming in our 30 BR Cartridge Guide. Here’s a short excerpt from that page — some tips provided by benchrest for score and HBR shooter Al Nyhus:
30 BR Case-Forming Procedure by Al Nyhus
The 30 BR cartridge is formed by necking-up 6mmBR or 7mmBR brass. You can do this in multiple stages or in one pass. You can use either an expander mandrel (like Joe Entrekin does), or a tapered button in a regular dies. Personally, I use a Redding tapered expander button, part number 16307. This expands the necks from 6mm to .30 cal in one pass. It works well as long as you lube the mandrel and the inside of the necks. I’ve also used the Sinclair expander body with a succession of larger mandrels, but this is a lot more work and the necks stay straighter with the Redding tapered button. This button can be used in any Redding die that has a large enough inside diameter to accept the BR case without any case-to-die contact.
Don’t be concerned about how straight the necks are before firing them the first time. When you whap them with around 50,000 psi, they will straighten out just fine! I recommend not seating the bullets into the lands for the first firing, provided there is an adequate light crush-fit of the case in the chamber. The Lapua cases will shorten from approx. 1.550″ to around 1.520″ after being necked up to 30-caliber I trim to 1.500″ with the (suggested) 1.520 length chambers. I don’t deburr the flash holes or uniform the primer pockets until after the first firing. I use a Ron Hoehn flash hole deburring tool that indexes on the primer pocket, not through the case mouth. — Al Nyhus
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October 26th, 2024
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion.
Cartridge Efficiency: A Primer (pun intended!) by USAMU Staff
The U.S. Army Marksmanship Unit (USAMU) published a series of reloading articles on its Facebook Page. In this article, the USAMU discusses cartridge case efficiency and its benefits. While this is oriented primarily toward NRA High Power Rifle and Long Range (1000-yard) competition, these factors also apply to medium/big game hunters. Assuming one’s rifle and ammunition are accurate, key considerations include ballistic performance (i.e., resistance to wind effects, plus trajectory), recoil, and throat erosion/barrel life.
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion. A classic example in the author’s experience involved a featherweight 7x57mm hunting/silhouette rifle. When loaded to modern-rifle pressures, just 43-44 grains of powder pushed a 139gr bullet at 2900 fps from its 22” barrel. Recoil in this light rifle was mild; it was very easy to shoot well, and its performance was superb.
An acquaintance chose a “do everything” 7mm Remington Magnum for use on medium game at short ranges. A larger, heavier rifle, it used ~65 grains of powder to achieve ~3200 fps with similar bullets — from its 26″ barrel. Recoil was higher, and he was sensitive to it, which hampered his shooting ability.
Similarly efficient calibers include the 6mm BR [Norma], and others. Today’s highly-efficient calibers, such as 6mm BR and a host of newer developments might use 28-30 grains of powder to launch a 105-107gr match bullet at speeds approaching the .243 Winchester. The .243 Win needs 40-45 grain charges at the same velocity.
Champion-level Long Range shooters need every ballistic edge feasible. They compete at a level where 1″ more or less drift in a wind change could make the difference between winning and losing. Shooters recognized this early on — the then-new .300 H&H Magnum quickly supplanted the .30-06 at the Wimbledon winner’s circle in the early days.
The .300 Winchester Magnum became popular, but its 190-220gr bullets had their work cut out for them once the 6.5-284 and its streamlined 140-142gr bullets arrived on the scene. The 6.5-284 gives superb accuracy and wind performance with about half the recoil of the big .30 magnums – albeit it is a known barrel-burner.
Currently, the 7mm Remington Short Action Ultra-Magnum (aka 7mm RSAUM), is giving stellar accuracy with cutting-edge, ~180 grain bullets, powder charges in the mid-50 grain range and velocities about 2800+ fps in long barrels. Beyond pure efficiency, the RSAUM’s modern, “short and fat” design helps ensure fine accuracy relative to older, longer cartridge designs of similar performance.
Recent design advances are yielding bullets with here-to-fore unheard-of ballistic efficiency; depending on the cartridge, they can make or break ones decision. Ballistic coefficients (“BC” — a numerical expression of a bullet’s ballistic efficiency) are soaring to new heights, and there are many exciting new avenues to explore.
The ideal choice [involves a] balancing act between bullet BCs, case capacity, velocity, barrel life, and recoil. But, as with new-car decisions, choosing can be half the fun!
Factors to Consider When Evaluating Cartridges
For competitive shooters… pristine accuracy and ballistic performance in the wind are critical. Flat trajectory benefits the hunter who may shoot at long, unknown distances (nowadays, range-finders help). However, this is of much less importance to competitors firing at known distances.
Recoil is an issue, particularly when one fires long strings during competition, and/or multiple strings in a day. Its effects are cumulative; cartridges with medium/heavy recoil can lead to shooter fatigue, disturbance of the shooting position and lower scores.
For hunters, who may only fire a few shots a year, recoil that does not induce flinching during sight-in, practice and hunting is a deciding factor. Depending on their game and ranges, etc., they may accept more recoil than the high-volume High Power or Long Range competitor.
Likewise, throat erosion/barrel life is important to competitive shooters, who fire thousands of rounds in practice and matches, vs. the medium/big game hunter. A cartridge that performs well ballistically with great accuracy, has long barrel life and low recoil is the competitive shooter’s ideal. For the hunter, other factors may weigh more heavily.
Cartridge Efficiency and Energy — Another Perspective
Former Lapua staffer Kevin Thomas explains that efficiency can be evaluated in terms of energy:
“Cartridge efficiency is pretty straight forward — energy in vs. energy out. Most modern single-based propellants run around 178-215 ft/lbs of energy per grain. These figures give the energy potential that you’re loading into the rifle. The resulting kinetic energy transferred to the bullet will give you the efficiency of the round. Most cases operate at around 20-25% efficiency. This is just another way to evaluate the potential of a given cartridge. There’s a big difference between this and simply looking at max velocities produced by various cartridges.”
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October 8th, 2024
We first ran this story a few years back. But it’s still a very interesting subject for benchrest shooters. Shown above, the 30 BR (a 6mmBR necked up to .30 caliber) currently rules the benchrest-for-score game. However, a 30 BR Improved offers some potential advantages, particularly when the winds are strong or tricky. In this article Al Nyhus explains his 30 BRX wildcat. Running Hodgdon H4198, Al says he gets an easy 150 – 200 FPS more than the conventional 30 BR. That can translate to less drift in the wind. It also lets you pursue a higher speed node, which can lead to improved accuracy with some barrels.
 Forum member Al Nyhus is a top-level score shooter who has competed successfully with the 30 BR cartridge in VFS (Varmint for Score) matches. Al has been working on an “improved” 30 BR cartridge that delivers extra velocity. Al’s 30 BRX cartridge is inspired by the 6mm BRX cartridge, popular in 600-yard benchrest and across-the-course competition. The 6mm BRX cartridge maintains the same sidewall profile and shoulder angle as the parent 6mmBR case. Likewise, the 30 BRX retains the 30° shoulder used on the popular 30 BR cartridge.
Al reports: “Thought you might like to see what I’ll be working with in my VFS gun this season. It’s a true 30 BRX — a 30 BR with the shoulder moved forward 0.100″ with the standard BR shoulder angle. Stan Ware of SGR Custom Rifles built one last season for Steve Grosvenor and I was really impressed by the performance of Steve’s gun. The 30 BR barrel on my VFS gun needed replacing, so the new 30 BRX got the nod.”
30 BRX Delivers 150-200 FPS More Velocity than 30 BR
Al says his 30 BRX gives a solid 150-200 fps speed gain over the 30 BR at the top, while needing just 2.5-3.0 more grains of Hodgdon H4198 to do so. A 30 BR case holds on average 40.8 grains of water, while the 30 BRX holds 42.3 grains (roughly 4% more). So the 30 BRX delivers a 7% increase in velocity with a mere 4% increase in H20 capacity. That’s pretty good efficiency. [Editor’s Note: Assuming 34 grains of H4198 is a typical 30 BR match load, Al’s increase of 2.5-3.0 grains for the 30 BRX represents roughly a 7.5-8.5% increase in actual powder burned. That explains the higher velocities.]
Why did Nyhus decide to try an “improved” 30 BR?
Al explains: “The 30 BRX was created to operate at a [higher] velocity level than can be achieved with the standard 30 BR case, while at the same time keeping the easy-tuning characteristics of the standard 30 BR case. We also wanted to use the same powders currently used with the 30 BR and maintain similar operating pressures.” Is the 30BRX harder to shoot because of the increased velocity? Al doesn’t think so: “In a 13.5-lb HV gun, the 30 BRX case is a pleasure to shoot with just a flea bite of recoil.”
Will the 30 BRX Become Popular in Score Competition?
The 30 BR is already an exceptionally accurate cartridge that dominates short-range Benchrest for Score competition. Will the 30 BRX make the standard 30 BR obsolete? Nyhus doesn’t think so. However, Al believes the 30 BRX offers a small but important edge in some situations: “On any given day, it’s the shooter that hits the flags best and makes the fewest mistakes that ends up on top. No amount of velocity will save you when you press the trigger at the wrong time. Missing a switch or angle change at 200 yards that results in 3/4″ of bullet displacement on the target can’t be compensated for with another 200 fps. That’s the hard fact of benchrest shooting. But on those days when, as Randy Robinett says, ‘our brains are working’, the BRX may offer enough of an advantage to turn a close-but-no-cigar 10 into an ‘X’ at 200 yards. Or turn a just-over-the-line 9 into a beggar 10.” Given the fierce competition in Score matches, an extra 10 or another X can make the difference between a podium finish and also-ran status.
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September 21st, 2024
 Many visitors to the site ask us, “I’ve got a .223 and .308. What will a 6mmBR Norma (6BR) give me that I’m not getting already?” Well first you will probably average consistently smaller groups than your current .223 or .308 rifle (assuming the 6BR has a quality barrel and trigger). A good .308 Winchester can be superbly accurate, no question about that, but the lesser recoil of the 6BR works in the shooter’s favor over a long string of fire. Even with a Rem 700 or Savage action factory action, a 6BR with a benchrest stock, premium barrel, and a high-quality chambering job should deliver 5-shot groups in the high twos to mid-threes, provided you do your job. We have one 6BR rifle that shoots Lapua factory-loaded 6BR ammunition in the low twos and high ones. That’s exceptional, we admit, but it still shows how the 6BR is an inherently accurate cartridge, even with factory loads.
Compared to a .223, the 6BR offers a much better selection of high-BC projectiles, and will deliver considerably more power on the target. So it’s a better choice for hunters and 600-yard benchrest shooters. Compared to the .308 Win shooting 168gr MatchKings, a 6BR shooting 105-107gr bullets offers better ballistics all the way out to 1000 yards. Plus, for most people, the 6BR is just easier to shoot than a .308 Win. Recoil is less than half of the .308 Win cartridge. Both the .308 and 6BR chamberings offer good barrel life, but the 6BR uses 15-18 grains less powder, saving you money. On the other hand the .308 Win is the designated cartridge for F-TR and Palma shooting, so it may be a more versatile chambering for Long-Range competition. So which would we choose between the 6BR and the .308? Actually we think you should have both. The 6BR is a favorite cartridge out to 500 yards, and we like the .308 Win for F-TR. The .308 Win has shown outstanding accuracy, as displayed last week at the NRA F-class Nationals in Arizona.
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September 8th, 2024
With the 6mm Dasher cartridge becoming popular with PRS/NRL competitors as well as the benchrest crowd, we thought it was time to re-visit a special rifle chambered for the 6mm Dasher wildcat. This gun has a great story behind it. Forum member Bob A. (aka “Killshot”) used his “Forum Classifieds Special” to beat all comers in the F-Class Division in the American-Canadian Match and the Long Range Regional Match in 2013 in Sacramento, CA.
Bob’s 6mm Dasher sports a blue-printed Rem 700 action. Who says you need a high-dollar custom action to run with the big dogs? In fact, this same gun, built with components sourced from AccurateShooter Forum Classified Ads, set a Sacramento F-Class range record of 200-17X a few years back. In this story, Bob talks about the build, and he explains his methods for loading ultra-accurate Dasher ammo.
Bob’s Budget-Build Dasher F-Classer
I wanted to build a proper rifle for F-Open but needed to keep it simple and, well, cheap. I found a solid “base” to build on in the form of a Dave Bruno-built, “pre-owned” 6-6.5×47 Lapua that I located in the AccurateShooter Forum classifieds in late 2011. The base action was a trued and blue-printed Remington 700 receiver circa 1971 with a spiral-fluted bolt. It was in a Shehane ST1000 stock painted sky blue and had a Jewell 1.5-oz BR trigger. I sent the bolt to Greg Tannel (Gretanrifles.com) to have the firing pin hole bushed and sleeved, the ejector removed and the hole filled and the face trued. I upgraded to Tannel’s Light Steel firing pin assembly while it was out.
Having the working bits completed, I needed a barrel. So I went to the AccurateShooter classifieds again and found a 1:8″-twist, 30″ x 1.25″ (diam.) Bartlein with a 0.236″-land bore. I called Dave Kiff and explained my pursuit and he recommended his PT&G “world record” 6 Dasher reamer (.2704″ no-turn neck and .104″ freebore). A month or so later the reamer and gauges arrived.
I had the barrel chambered by Marc Soulie of Spartan Precision Rifles (510-755-5293, Concord, CA). Marc is a great builder and I’m pleased to call him a friend.
The rifle got its good looks from a Pennsylvania artist named Kenny Prahl. His Prahl Designs shop (724-478-2538) added the white ghost-flames over the existing sky blue metallic paint.
Looks Great, Shoots Better
Fire-forming showed great promise — ten-shot groups of half an inch at 200 yards were typical. I lost only one case to a split neck and the “blow lengths” are good and consistent. This was followed up with load development which saw 100-yard, five-shot groups in the .1s and .2s as the rifle showed its preference for Reloder 15 over Varget powder, and for CCI 450s over all other primers. The bullet of choice was the ever-popular Berger 105gr Hybrid Target.
In February 2012 I began shooting the Dasher in monthly club matches at the Sacramento Valley Shooting Center, the home range of a number of excellent F-Class, Benchrest and High Power shooters. Using a Farley Coaxial rest up front (also picked up from a WTB ad on AccurateShooter’s Forum) and an Edgewood bag in the back, I gradually improved my gun-handling to the point where I could shoot a respectable score. This was very different from the bipod shooting I’d done in the past in F/TR.
 Dasher Loading Tips
My chamber is set up for blue box Lapua 6mmBR brass. My case preparation is straight-forward. I fire-form with virgin cases right out of the box. I don’t size them but I will give the primer holes a good look and clean up the flash hole with a .058″ bit in a pin vise. To fire-form, I seat a Berger 108gr BT .030″ into the lands over a standard 6mmBR load of Varget.
For match loads, I use Alliant Reloder 15. While Varget is less sensitive to temp changes, RL15 has given me lower extreme spreads and better long range control. [Bob acknowledges that every barrel is unique, so a different powder, such as H4895 might work better for you.]
I clean my fired cases with stainless steel media in a Thumler’s rotary tumbler after every firing. I anneal after every other firing using a Bench-Source machine which is very well made and easy to operate. I use a Whidden full length bushing die with Redding bushings for sizing.
After sizing, I chamfer the inside of the neck with the K&M tool which has a pilot rod centered in the flash hole. Then I’ll give the neck and mouth a “once over” with some 0000 steel wool. I finish loading off with a Redding Competition Seating Die with the micrometer top.
 I use a carbide ball on the expander rod of the full length sizing die. I use a .266″ TiN-coated bushing and the ball just kisses the inside walls of the sized neck. I get very consistent neck tension this way and have had no issue with split necks.
Seating Depth Considerations
With fire-formed brass, the junction of the bullet’s bearing surface and boat-tail is above the neck/shoulder junction of the case, so I have no issues with donuts. You can see how a loaded round looks in the photo at left. For occasional trimming, I use a very nice little Possum Hollow trimmer that indexes on the case shoulder.
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December 31st, 2023
This story first ran in 2010. But to mark our long-standing friendships with shooter Joe Friedrich and chassis builder Gary Eliseo, we wanted to reprise the article for the new year, with 2024 just hours away. Joe’s Eliseo-chassis 6mmBR rifle delivered some of the most amazing accuracy with factory ammo we’ve ever seen, in any rifle, in any caliber.
 Amazing Accuracy from 6mmBR Tubegun
What kind of accuracy do you think a tubegun can deliver with factory ammo — during barrel break-in? Perhaps 0.6″ at 100 yards, half-MOA if the conditions are perfect? Well you may want to change your preconceptions about tubeguns — and factory ammo. This Eliseo R5 repeater, smithed by John Pierce with a Pierce CM action and Broughton 5C barrel, shot the Lapua 90gr factory ammo into flat ONEs during the break-in session. A day later, in tricky 8-14 mph winds, the gun nailed a witnessed and software-measured 0.174″ 5-shot group using the 105gr factory ammo. That would be impressive for a “full-race” benchgun with precision handloads. For an across-the-course rifle shooting factory ammo, it’s pretty amazing.
Eliseo Tubegun Shoots in the Ones
This accurate rifle belongs to our friend (and designated expert trigger-puller) Joe Friedrich. During the initial break-in session, since his reloading dies had not yet arrived, Joe decided to start with some Lapua factory-loaded 6BR ammo he had on hand. After doing a few two-shot-and-clean cycles (with patches and nylon brush), Joe decided to try a 3-round group just to see if the Broughton barrel had some potential. To his astonishment, the Eliseo R5 put three rounds in 0.100″ (photo below left). Joe then cleaned the barrel again, shot a couple foulers and tried a 4-shot group. The results were just as stunning — 4 shots in a mere 0.104″ but three in virtually one hole (photo below right).
 
 |
Joe’s Orange 6mmBR Tubegun SPECS
Chassis: Eliseo R5 Repeater, fitted with Eliseo Front Sled and Rear Bag-Rider.
Gunsmithing: Pierce Engineering Ltd..
Chambering: 6mmBR Norma, .272″ No-turn Neck, approx. 0.090″ freebore.
Action: Pierce Engineering, Rem 700 footprint, Chrome-Moly, fluted bolt.
Barrel: Broughton 5C (Canted Land), 27.5″, 1:8″ twist, Medium Palma contour.
Trigger: CG X-Treme Two-Stage.
Optic: March 10-60x52mm.
Ammunition: Lapua 6mmbr 90gr Scenar BT (#4316045, non-moly), 105gr Scenar BT (#4316046, non-moly ). |
 You Can’t Believe How This Gun Shoots
Joe called your Editor and said “You can’t believe how this gun shoots with factory ammo!”. So we arranged a photo session for the next afternoon, where I could verify the rifle’s accuracy. Well it turned out the conditions were way more challenging than when Joe broke in the barrel the day before. Winds were running 8-14 mph and were swinging through 180 degrees half-way down the range. Joe fired a few 90s through the Oehler chronograph at my request, then opened a box of Lapua 105gr factory ammo. It took about four rounds for the barrel to settle in after being cleaned the night before. Then Joe got serious, and with your Editor looking over his shoulder, he drilled a 0.174″ five-shot group in switching winds, doping every shot. Joe felt the gun could have shot tighter but he missed one wind call.
Serious Accuracy with a Multi-Purpose Rifle
So there you have it — a tubegun that shoots in the ones with factory ammo. Joe says that, at least with the 90s, the Elesio R5 shoots as well as his 6 PPC. Joe stressed that “steering the tubegun is hard work. You really have to concentrate compared to a purpose-built bench gun like my PPC. With the tubegun, everything has to be perfect on every shot — hand position, cheek position, stock position in the bag. If you’re off just a little bit, it’s easy to steer the gun the wrong way and send a shot out of the group.”
Accuracy Great But Fouling Heavy and ES Could Be Better
Have there been any negatives to Joe’s 6BR tubegun experiment so far? Well, the Broughton 5C barrel, while phenomenally accurate, shows signs of being a bad fouler. Copper built up pretty quickly over the first 25 rounds or so. We saw best accuracy with a recently-cleaned barrel. Hopefully the fouling will lessen as the barrel polishes in with use. And the canted land barrel is slower than average with the factory ammo. Lapua rates its 90gr naked-bullet ammo at 2950 fps with a 26″ tube. In Joe’s 27.5″ barrel we only averaged 2901 fps. With the 105gr factory ammo, which is rated at 2790 fps, we averaged just 2694 fps. That’s quite disappointing. Also the ES on the factory ammo, slightly over 50 fps for both bullet types, wasn’t particularly good. Still, the overall results were stunning. This gun shoots better than many long-range benchrest rifles running carefully-developed handloads — and it does that with factory ammo, right out of the box.
Joe Friedrich is a superb benchrest shooter, who has won many matches and set National Records in ARA rimfire benchrest competition. Here is Joe with “Sweet Pea”, his favorite .22 LR rimfire rig. With over 100,000 rounds through the Benchmark barrel, this well-worn rifle set an ARA 4-target Aggregate record! READ about Sweat Pea Record HERE.
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November 8th, 2023
Many visitors to the site ask us, “I’ve got a .223 and .308. What will a 6mmBR Norma (6BR) give me that I’m not getting already?” Well first you will probably average consistently smaller groups than your current .223 or .308 rifle (assuming the 6BR has a quality barrel and trigger). A good .308 Winchester can be superbly accurate, no question about that, but the lesser recoil of the 6BR works in the shooter’s favor over a long string of fire. Even with a Rem 700 or Savage action factory action, a 6BR with a benchrest stock, premium barrel, and a high-quality chambering job should deliver 5-shot groups in the high twos to mid-threes, provided you do your job. We have one 6BR rifle that shoots Lapua factory-loaded 6BR ammunition in the low twos and high ones. That’s exceptional, we admit, but it still shows how the 6BR is an inherently accurate cartridge, even with factory loads.
Compared to a .223, the 6BR offers a much better selection of high-BC projectiles, and will deliver considerably more power on the target. So it’s a better choice for hunters and 600-yard benchrest shooters. Compared to the .308 Win shooting 168gr MatchKings, a 6BR shooting 105-107gr bullets offers better ballistics all the way out to 1000 yards. Plus, for most people, the 6BR is just easier to shoot than a .308 Win. Recoil is less than half of the .308 Win cartridge. Both the .308 and 6BR chamberings offer good barrel life, but the 6BR uses 15-18 grains less powder, saving you money. On the other hand the .308 Win is the designated cartridge for F-TR and Palma shooting, so it may be a more versatile chambering for Long-Range competition. So which would we choose between the 6BR and the .308? Actually we think you should have both. The 6BR is a favorite cartridge out to 500 yards, and we like the .308 Win for F-TR. The .308 Win has shown outstanding accuracy, as displayed last week at the NRA F-class Nationals in Arizona.
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September 24th, 2023
They say that a man can never have too much money or too much time. Darrell Jones would add that a man can never have too many BR-based rifles. Darrell had a fleet of BRs, in 22 BR, 6mm BR, 6.5 BR, 7 BR, and 30 BR. But he was intrigued by the potential of a rifle in the .257 caliber. Could it shoot as well as a 6mm BR? Could it challenge the more popular calibers in the highly competitive 600-yard benchrest game? Through careful research and component selection, Darrell created a 25 BR rifle that proves the viability of the 25 BR as a competition round. Pushing 115gr high-BC Berger bullets at 2837 fps, Darrell’s 25 BR “Peppermint” won first place in its very first match.
The Barely Bigger BR — Exploring the .25 Caliber Option
Rifle Report by Darrell Jones
I decided to build a 25 BR after several weeks of deliberation and ruling out a .257 Ackley Improved. Part of my dilemma was that I wanted to shoot F-Class competition at 600 yards, and I was unsure about the accuracy potential of the 25 BR. However, I currently have several BRs chambered in 22 BR, 6BR, 6.5 BR, 7 BR, and 30 BR and they all shoot exceptionally well at 600 yards. This lead me to believe a 25 BR should deliver fine accuracy, just like its other BR siblings. Why wouldn’t a 25 BR shoot accurately provided that I built it with the right components? The feasibility saga began. I began searching diligently for custom 25-caliber bullets. Unfortunately, there are not many 25-caliber custom bullet makers. I actually found only two custom bulletsmiths who produce the 25s. I did look at Fowlers and then looked at Bergers. Both Jeff Fowler and Berger made 110-grain flat-base bullets when I was looking. [Editor — this 110gr bullet is no longer listed by Berger]. The Berger 110gr FB bullets (.414 ballistic coefficient) shot very well out of my 12-twist 25-06 Ackley. However, I wanted to shoot a heavier bullet if possible. Berger makes a 25-caliber 115gr VLD boat-tail with a high ballistic coefficient. This needs a 10-twist barrel.
Panda Action, McMillan Stock, Weaver T-36
As you can see, I went with a Panda polished action and a weighted McMillan BR stock painted metallic silver with red candy cane stripes thus the name “Peppermint”. This gun actually does double duty now as a 25 BR and 6 PPC switch barrel. When I want to run the gun as a 6 PPC for short range, I simply screw on the PPC barrel, then swap in a bolt (fitting the PPC bolt face) from another Panda action I own. That’s one advantage of owning custom Kelbly actions! Don’t even think about exchanging bolts between factory guns. Kelbly rings and a Weaver T-36 fixed-power scope handle the optical duties while a Jewell trigger set at one ounce takes care of the firing mechanism.
Chambering for the .25 Caliber BR Wildcat
I wanted a chamber that would let me shoot both the 110s and the 115s. I took some time surfing the net looking for rental reamers that had suitable throat dimensions. I found that Elk Ridge Reamer Rentals had a 25 BR pilot reamer available. I called and Elk Ridge faxed me a reamer diagram that indicated it was designed to tight SAMMI specs. I asked how often was the reamer used and was told “not very often”.
 I did want a minimum no-turn neck optimized for Lapua brass. The drawing indicated that the reamer would cut a .281″ neck and a throat of 1.0315″. This was very close to ideal, though I did have to turn two thousandths off the necks of Lapua 6BR brass after I necked it up. I resized using a .277″ bushing and the loaded rounds came out to be .279″. Realizing that this was in the ball park, I decided to go with the Elk Ridge Reamer and build a 25 BR that could shoot 110gr or 115gr bullets. Now the question was where to get a match-grade 25-caliber barrel. I called quite a few of the custom barrel-makers, including BlackStar Barrels in Texas (no longer operating). I have had wonderful success with the BlackStar barrel on my 6BR “Chantilly” — it delivered great accuracy and impressive velocities. Since the 25 BR was so similar, I went with another BlackStar. I ordered a 10-twist, 6-groove, 1.250″-diameter straight-contour tube.
 After chambering, the barrel finished at 1.245″ diameter and 27.5″ inches with an 11° crown. I actually had the throat lengthened to accept both Berger 110gr and 115gr bullets. The bases of the FB 110-grainers sit flush with the neck-shoulder junction, when they are seated .010″ into the lands. With the longer 115gr VLDs, the bottom of the bearing surface (i.e. start of boat-tail) is just about even with the neck-shoulder junction.
Accurate Load Development
The barrel broke in easily with just 10 shots, using a “shoot one and clean” process. The load I started with was 31.5 grains of Varget with CCI 450 primers. The Berger 110s and Berger 115s had the same Point of Impact (POI) at 100 yards. However, the 115s impacted two inches higher at 600 yards with the same load. That shows the benefits of a higher BC. Pushed by the CCI 450s and 31.5 grains of Varget, the 115-grainers were running about 2837 FPS. I boosted the load up to 32.0 grains but I noticed primer cratering, so I backed off, settling on 31.5 grains for the 115gr Berger VLD.
Peppermint Wins at 600 Yards
 For her debut in competition, I took “Peppermint” to our local 600 yard F-class match. Shooting the Berger 115s with 31.5 grains Varget, she won with a perfect score of 200 with 14 Xs. At my club, we use a SR3 target. The X-Ring measures 3″ in diameter and the 10-Ring measures 7″. At the match there were some very good shooters with top-flight custom rifles in accurate calibers such as 6.5-284 and 22 Dasher. I was very fortunate to come out on top, but I give the credit to Peppermint’s good bench manners and outstanding accuracy.
As you can see from the target, “Peppermint” is a very accurate rifle that has proven herself in competition. It takes a good gun to finish “on top” in her very first match. So far, I’m very happy with the project, and more than satisfied with the accuracy of the 25 BR. This is definitely a worthy cartridge for Egg Shoots, 500m varmint matches, and the 600-yard F-Class game.
| BR-Based Cartridge Comparison |
| CALIBER |
22 BR |
6mm BR |
25 BR
| 6.5 BR |
7 BR
| 30 BR |
| Bullet |
80gr SMK |
107gr SMK |
115gr Berger |
107gr SMK |
130gr SMK |
118gr BIB |
| BC |
.420 |
.527 |
.522 |
.420 |
.391 |
na |
| Load Grains |
31.0 H4350 |
30.0 Varget |
31.5 Varget |
32.0 Varget |
34.0 AA2460 |
34.0 H4198 |
| Barrel Length |
27″ |
27″ |
27.5″ |
27.5″ |
28″ |
24″ |
| Velocity |
3100 fps |
2880 fps |
2837 fps |
2851 fps
| 2719 fps |
2970 fps |
Comparing the BR-Based Variants
 Now that I have several calibers in the BR cartridge family, (22 BR, 6mm BR, 6.5 BR, 7 BR, and a 30 BR), it is my humble opinion that they each have their own place. A varmint hunter’s dream, the 22 BR can push a bullet faster and more accurately than the 22-250. With an 8-Twist barrel, the 22 BR can send an 80gr SMK to 600 yards with extreme accuracy.
The 6 BR can do it all. The 6mm caliber offers a wide variety of quality bullets suitable for any shooting situation. All the major custom barrel makers produce outstanding 6mm barrels in a full range of twists. Moreover, since the 6 BR cartridge is so popular, there is a great store of knowledge about reloading for the 6 BR. It is easy to find a load that will shoot superbly in any bullet weight.
The 25 BR has proved to be easily tuneable, proficient and not fickle. You can obtain extreme accuracy without great effort in load development. The 115gr Berger offers a good high-BC projectile for this caliber, making the 25 BR a viable alternative to the 6 BR. As I’ve shown, it is competitive with a 6 BR in head to head competition.
Compared to the 25 BR, the 6.5 BR has a small edge in ballistics. However, there are not many light bullet choices available, especially from custom makers. The 123gr Lapua Scenar is an excellent bullet with a .547 stated BC, but it may be a bit heavy for the case capacity.
The 7 BR was designed for silhouette shooting, and it excels at that task. The 7 BR can push a 130 grain bullet fast enough to knock over the steel silhouettes at 500 meters with real consistency.
The 30 BR is nothing less than outstanding. The 30 BR is now the dominant cartridge on the benchrest Score-shooting circuit. It is also highly accurate for group shooting at 200 yards and very capable of winning a 600-yard F-Class match. Barrel life of over 6,000 rounds is realistic.
I like all the “flavors” of BR derived from the 6mm BR Norma case. However, if I could only have one BR in my safe, give me my 8-Twist, 6 BR “Chantilly” and I will be a happy camper. The final point I would make is if a cartridge is stamped BR on the case, it will shoot extremely accurately if you can.
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August 15th, 2023
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion.
Cartridge Efficiency: A Primer (pun intended!) by USAMU Staff
The U.S. Army Marksmanship Unit (USAMU) published a series of reloading articles on its Facebook Page. In this article, the USAMU discusses cartridge case efficiency and its benefits. While this is oriented primarily toward NRA High Power Rifle and Long Range (1000-yard) competition, these factors also apply to medium/big game hunters. Assuming one’s rifle and ammunition are accurate, key considerations include ballistic performance (i.e., resistance to wind effects, plus trajectory), recoil, and throat erosion/barrel life.
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion. A classic example in the author’s experience involved a featherweight 7x57mm hunting/silhouette rifle. When loaded to modern-rifle pressures, just 43-44 grains of powder pushed a 139gr bullet at 2900 fps from its 22” barrel. Recoil in this light rifle was mild; it was very easy to shoot well, and its performance was superb.
An acquaintance chose a “do everything” 7mm Remington Magnum for use on medium game at short ranges. A larger, heavier rifle, it used ~65 grains of powder to achieve ~3200 fps with similar bullets — from its 26″ barrel. Recoil was higher, and he was sensitive to it, which hampered his shooting ability.
Similarly efficient calibers include the 6mm BR [Norma], and others. Today’s highly-efficient calibers, such as 6mm BR and a host of newer developments might use 28-30 grains of powder to launch a 105-107gr match bullet at speeds approaching the .243 Winchester. The .243 Win needs 40-45 grain charges at the same velocity.
Champion-level Long Range shooters need every ballistic edge feasible. They compete at a level where 1″ more or less drift in a wind change could make the difference between winning and losing. Shooters recognized this early on — the then-new .300 H&H Magnum quickly supplanted the .30-06 at the Wimbledon winner’s circle in the early days.
The .300 Winchester Magnum became popular, but its 190-220gr bullets had their work cut out for them once the 6.5-284 and its streamlined 140-142gr bullets arrived on the scene. The 6.5-284 gives superb accuracy and wind performance with about half the recoil of the big .30 magnums – albeit it is a known barrel-burner.
Currently, the 7mm Remington Short Action Ultra-Magnum (aka 7mm RSAUM), is giving stellar accuracy with cutting-edge, ~180 grain bullets, powder charges in the mid-50 grain range and velocities about 2800+ fps in long barrels. Beyond pure efficiency, the RSAUM’s modern, “short and fat” design helps ensure fine accuracy relative to older, longer cartridge designs of similar performance.
Recent design advances are yielding bullets with here-to-fore unheard-of ballistic efficiency; depending on the cartridge, they can make or break ones decision. Ballistic coefficients (“BC” — a numerical expression of a bullet’s ballistic efficiency) are soaring to new heights, and there are many exciting new avenues to explore.
The ideal choice [involves a] balancing act between bullet BCs, case capacity, velocity, barrel life, and recoil. But, as with new-car decisions, choosing can be half the fun!
Factors to Consider When Evaluating Cartridges
For competitive shooters… pristine accuracy and ballistic performance in the wind are critical. Flat trajectory benefits the hunter who may shoot at long, unknown distances (nowadays, range-finders help). However, this is of much less importance to competitors firing at known distances.
Recoil is an issue, particularly when one fires long strings during competition, and/or multiple strings in a day. Its effects are cumulative; cartridges with medium/heavy recoil can lead to shooter fatigue, disturbance of the shooting position and lower scores.
For hunters, who may only fire a few shots a year, recoil that does not induce flinching during sight-in, practice and hunting is a deciding factor. Depending on their game and ranges, etc., they may accept more recoil than the high-volume High Power or Long Range competitor.
Likewise, throat erosion/barrel life is important to competitive shooters, who fire thousands of rounds in practice and matches, vs. the medium/big game hunter. A cartridge that performs well ballistically with great accuracy, has long barrel life and low recoil is the competitive shooter’s ideal. For the hunter, other factors may weigh more heavily.
Cartridge Efficiency and Energy — Another Perspective
Former Lapua staffer Kevin Thomas explains that efficiency can be evaluated in terms of energy:
“Cartridge efficiency is pretty straight forward — energy in vs. energy out. Most modern single-based propellants run around 178-215 ft/lbs of energy per grain. These figures give the energy potential that you’re loading into the rifle. The resulting kinetic energy transferred to the bullet will give you the efficiency of the round. Most cases operate at around 20-25% efficiency. This is just another way to evaluate the potential of a given cartridge. There’s a big difference between this and simply looking at max velocities produced by various cartridges.”
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