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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
Share the post "Forming 30BR Cases — Experts Explain the Best Methods"
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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December 11th, 2022
 The 30BR is an amazing little cartridge. However, 30BR shooters do have to neck-up 6mmBR 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 30BR necks after expansion: “Everything I have found on 30BR 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 30BR who help prove and popularize the 30 BR for benchrest score shooting. Randy offers this advice on 30BR 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 30BR Cartridge Guide on AccurateShooter.com
You’ll find more information on 30BR 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:
30BR Case-Forming Procedure by Al Nyhus
The 30BR cartridge is formed by necking-up 6BR or 7BR 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 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.
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June 23rd, 2020
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 21st, 2018
Forum member Al Nyhus is a top-level score shooter who has competed successfully with the 30BR 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’s testing shows the 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 30BR match load, Al’s increase of 2.5-3.0 grains for the 30BRX 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 30BR case, while at the same time keeping the easy-tuning characteristics of the standard 30BR case. We also wanted to use the same powders currently used with the 30BR and maintain similar operating pressures.” Is the 30 BRX 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 Replace the 30 BR 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.
By popular request, this story has been reprinted from 2011.
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August 7th, 2016
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 Replace the 30 BR 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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July 30th, 2014
The 30BR is an amazing little cartridge. However, 30BR shooters do have to neck-up 6mmBR 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 30BR necks after expansion: “Everything I have found on 30BR 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 30BR who help prove and popularize the 30 BR for benchrest score shooting. Randy offers this advice on 30BR 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 30BR Cartridge Guide on AccurateShooter.com
You’ll find more information on 30BR 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:
30BR Case-Forming Procedure by Al Nyhus
The 30BR cartridge is formed by necking-up 6BR or 7BR brass. You can do this in multiple stages or in one pass. Most of the top shooters prefer the single-pass method. 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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July 8th, 2014
 In the short-range benchrest game, most of the attention goes to the 10.5-lb Light Varmint Class, and the 13.5-lb Heavy Varmint Class. But there’s another class that is enjoying increased popularity — Hunter Benchrest. In some ways, Hunter BR is more challenging, because you shoot a 10-pounder with a narrower (2.25″ forearm) and a 6-power scope (both LV and HV allow 3″-wide forearms and high-magnification scopes). It takes skilled gun-handling and careful aim to get the most from a Hunter Benchrest rig.
 The modern Hunter BR rifle is a far cry from a typical deer rifle, or even a walk-around varminter. Jackie Schmidt explains: “Do not be fooled by that title ‘Hunter Benchrest’, or HBR. The typical HBR Rifle has, like its cousin the Group Rifle, evolved into a very singular-purpose piece of equipment, suited to do one thing very well — namely to shoot Xs in the competitive arena, governed by rather strict sets of rules promulgated by the IBS or the NBRSA.
Hunter Benchrest Rifle Standards
The two defining factors in HBR are the minimum case capacity, and the 6-power scope. Everything else is just window dressing. Can one shoot a real factory gun in Hunter BR Class? YES — IF your factory rifle meets these qualifications:
■ Total gun weight no more than 10 pounds.
■ Stock forearm must be convex (at least slightly) on the bottom, and no more than 2.25″ wide.
■ Gun must have magazine capable of holding at least two cartridges. (Normally, however, Hunter BR shooters don’t feed from the magazine.)
■ Gun must shoot cartridge with at least 45 grains of H20 capacity (same as a 30-30).
■ Scope must be a 6-power or capable of being set and used at 6X magnification.
If you go to the IBS website, you will see that there are a couple of exceptions, but in the end, to compete for the prize, you must have a legal Hunter BR rifle. But even if you’re not completely within the rules, most match directors will let a newcomer shoot along, for the fun of it, and to see what the game is really all about.”
Top Hunter BR shooter Al Nyhus tells us: “As Jackie has pointed out, the Hunter class in Benchrest has mutated into full race BR rigs…much like NASCAR ‘stock cars’ or NHRA ‘Pro Stock’. The original intent of Hunter was for a class where the average person with an interest in accuracy could bring a good shooting hunting rifle and give BR a try. Still a darn good idea, to me.
Hunter Benchrest Rig Chambered for the .30 Wolfpup
Here are photos of my Hunter Benchrest rig, which is pretty typical of what’s being used at this point in time. My Hunter BR rig is pretty standard stuff except for the chambering. It features a Stolle R/L Kodiak action tweaked a bit by Stan Ware, Kostyshyn 1:17 four groove, chambered for Stan Ware’s 30 WolfPup (30BR .240″ long/.085″ neck length). The photo below shows a Leupold 6X scope but I’ve been using a Sightron 6X lately.
This stock is an old Speedy/McMillan pattern HBR stock. I had it dipped (externally coated) with a carbon fiber pattern. By the rules, Hunter rifles cannot be glue-ins, so pillar-bedding is the norm. I guess the forearm is about as ‘convex’ on the bottom as any other stock currently in use. This is another area where the guns have evolved and the rulebook(s) haven’t exactly kept pace with the current state of what’s being used.”
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November 2nd, 2013
By popular request, this story has been reprinted from 2011.
Forum member Al Nyhus is a top-level score shooter who has competed successfully with the 30BR 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’s testing shows the 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 30BR match load, Al’s increase of 2.5-3.0 grains for the 30BRX 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 30BR case, while at the same time keeping the easy-tuning characteristics of the standard 30BR case. We also wanted to use the same powders currently used with the 30BR 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 Replace the 30 BR 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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