|
|
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
Share the post "Forming 30BR Cases — Experts Explain the Best Methods"
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.”
Share the post "Cartridge Efficiency — Bullet Velocity and Energy Vs. Case Volume"
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.
Share the post "30 BRX — This 30 BR Improved Adds 150+ FPS for Score Shooting"
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.
Share the post "Recoil Energy Comparison — .223 Rem vs. 6mmBR vs. .308 Win"
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.
Share the post "Sunday GunDay: 6mm Dasher F-Classer — Winning Budget Build"
June 23rd, 2024
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.
Share the post "1.240″ Group at 500 Yards — PacNor Barrels Can Definitely Shoot"
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.
Share the post "Sunday GunDay: Joe’s Ultra-Accurate 6mmBR Eliseo Tubegun"
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.
Share the post ".308 Win vs. 6BR vs. .223 Rem — Recoil Energy Comparison Chart"
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.
Share the post "Sunday GunDay: 25 BR Benchrest Rig — The .25 Caliber Option"
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.”
Share the post "Cartridge Efficiency — Factors to Consider"
October 7th, 2022
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.
Share the post "30 BRX: An Improved 30 BR — More Speed for Better Ballistics"
June 8th, 2022
Get WAY Better Groups with New Criterion Pre-Fit Custom Barrel
 In our Shooters’ Forum, you’ll find a lengthy thread about accuracy problems with a Savage LRPV, chambered in 6mmBR. The gun would repeatedly split groups at 100 yards, and at 300 yards, the “flyers” would open up the groups to 1.5 MOA or larger. Interestingly, the factory test target (at right) showed a split group — not a good sign.
The gun’s owner, forum member LR_Shooter, tried a variety of tweaks: “I did this, done that… [changed] torque, tang floated, bedded action, recut chamber, and [adjusted firing pin]”. But nothing really helped. Frustrated, LR_Shooter asked his fellow Forum members for help. Much advice was proffered, including the novel idea of removing the middle action screw in the Savage 3-screw target action. Some of the advice proved helpful, but none of the suggested remedies produced a major improvement. This rifle, out of the box, tossed flyers and no amount of tweaking (or changes in shooting technique) really cured the basic problem. That is, until, the factory barrel got replaced…
New Criterion Pre-Fit Barrel Works Wonders
LR_Shooter acquired a Criterion pre-fit barrel from Jim Briggs at Northland Shooters Supply (NSS). These pre-fits are designed for easy installation with the standard Savage barrel nut. Wouldn’t you know it, with a new 30″ heavy-contour barrel on the LRPV, the gun started shooting way better. No more crazy fliers, no more split groups, no more excessive vertical. And the improvement came without any other major modifications. LR_Shooter reports: “I got a replacement barrel from Jim at NSS. It is a 30″ bull Criterion barrel. So far, without playing with torque screws and having my old setup… I’m very satisfied with the barrel I got. Now I have no problem getting [groups] under 0.25 MOA. Finally this thing can shoot!” The targets below, shot with the new Criterion barrel, speak for themselves. The left target was shot at 100 yards, while the target on the right was shot at 300 yards (very impressive).
Targets Shot with Savage LRPV Fitted with Criterion Barrel
Read Thread on Savage Accuracy Issues Fixed By Criterion Barrel
Moral of the Story — Sometimes A New Barrel Really Is the Right Solution
All of us have struggled at times with a rifle that won’t live up to expectations. This Editor personally struggled for over a year with a .260 Rem Savage with a factory tube. The gun tended to split groups and the POI walked as the barrel heated. I tried one powder/primer combination after another, working through a variety of seating depths over many months. I was persistent. Out of stubbornness, I just believed that sooner or later I’d find the magic load.
Well folks, sometimes there’s really nothing you can do about a sub-par barrel. It is what it is. To really improve a gun’s accuracy (particularly a gun with a factory tube), you may need to open your wallet and get a quality aftermarket barrel. Spending months trying one recipe after another may simply be an overwhelming waste of powder, bullets, and your precious time.
Albert Einstein supposedly said: “Insanity is defined as doing the same thing over and over again, and expecting different results.” Well that sort of describes my efforts with my .260 Rem. Once I had enough evidence that my barrel split groups no matter what load combo (and seating depth) I tried, it was time to pony up for a new barrel. When I did finally screw on a nice PacNor 3-groove SuperMatch, that Savage suddenly became a true tack-driver. As re-chambered in 6mmBR with the Pac-Nor, in calm conditions, my Savage will now consistently shoot in the twos with heavy bullets, and it can sometimes dip down into the ones with Berger 80gr flat-base bullets. The moral of the story here is simple — don’t waste weeks or months chasing your tail with a barrel that just won’t deliver (after a reasonable amount of testing). Save up for a custom barrel, get it chambered properly, and stop your cycle of frustration.
Share the post "Pre-Fit Solution — Don’t Waste Time with a Funky Factory Barrel"
|
