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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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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Sebastian (“Seb”) Lambang, the brilliant designer/builder of SEB Shooting Rests, is also one darn good shooter, as demonstrated at a recent major rifle competition in Australia. Shooting at multiple yardages from 300 to 1000 yards, Seb won the Queens Series F-Open title, and finished third overall in the Duncan & Queens Series Grand Agg. That’s mighty good marksmanship considering it was done with an F-Open rifle Seb had just acquired and never shot before! Congrats to Seb for his outstanding performance!
One of the factors in Seb’s success was an all-new front rest that Seb designed and crafted himself. This new SEB NEO-X rest has many advanced features including a swivel-adjusting head, a wide footprint, and the ability to fold-up for easier transport. We have a full report on the impressive NEO-X rest in this story, with bench testing videos by F-Class John.
The 2022 QRA Duncan & Queens Series in Australia
Report by Sebastian Lambang
This was my first overseas travel since the Berger Southwest Nationals in early 2020 [right before the COVID-19 shutdowns]. Three years ago I participated in the WARA Queens 2019 in Perth shooting the F-TR, and this was my second F-Open match in Australia. Usually I shoot the F-TR division. However this year I was invited to shoot the F-Open in the QRA Queens 2022 by Jason Mayers, my Australian dealer. Jason has been my “Little Big Brother” and my best friend in Australia. So why not? Let’s just do it!
Jason has two, twin F-Open guns. I bought one and used it during this match. Chambered for 7mm RSAUM, this F-Open rifle features a Barnard action, Marty Lobert trigger, Bartlein barrel with a large tuner in the front, McMillan Kestros ZR stock, and a Nightforce scope. I was shooting 7mm 180gr Berger bullets.
Jason did all of the load development, provided the ammunition and all equipment needed to shoot. The rifle shot and tracked very well — I loved it! Yes, I used a NEO-X prototype unit during the Queens match, i.e. the one that Jason used during the Duncan matches. The second unit just came in the day before the Queens started, it is set for left-handed shooter like him. I used his NEO rest during the Duncan Series.
We had various conditions during the match, from sunny, misty and rainy, to dead calm conditions and switchy wind. I was very fortunate to be able to pick the right time and shot well in the final 900 and 1000-yard stages, winning both yardages! With those results at 900/1000 I finished first in the Queens Match in F-Open. I then finished third overall in the Duncan & Queens Series F-Open Grand Aggregate.
Jason Mayers (L) and Seb Lambang (R). Seb had never shot this F-Open rifle before he piloted it to victory in the 2022 QRA Queens match.
Overcoming Challenges — Rifle Suffers Trigger Failure
I had a trigger failure which caused my score to drop by at least 2 points in the 1000-yard session just before the final day. I dropped 4 points in a good condition and it made me really upset! But huge thanks must go to Mark Fairbairn. Mark helped me to fix the rifle and loaned me a trigger so I still had a few minutes to finish the string!
After that trigger problem I chose to not give up! I hoped for a miracle, to be able to choose the right time to start to shoot (wind wise), to be good enough in reading the current conditions and to get the best possible scores! Jason’s encouragement in the morning that I could still win the match really helped boost my motivation! I do not know why or how but I retained confidence to shoot well and to win the match.
Thanks to Family, Friends, and Fellow Competitors
My sincere thanks to my lovely wife Lily who always supports and loves me as what I am all the time! Thanks again to my Little Big Brother Jason Mayers who has always helped and supported me genuinely! Without his help and support I wouldn’t have been able to win the match so it’s a more about him than me. My Thanks to QRA and all of the Match Organizers, Range Officers, Staffers, and Volunteers during the championship. My thanks also to all competitors and for the warmth and generous welcome!
Thoughts about the New NE0-X from its Inventor
I am really happy that the NEO-X works as expected, too. I think my effort to make even a better rest has been paid off. The New NEO-X combines the best features from the NEO rest and Mini rest in one package with a few extra features. The new NEO-X is designed for those who seek a light-compact rest and want the best one!
Great Scores Shot by Seb Lambang with new NEO-X Front Rest
Seb shot superbly to win the Queens Series in F-Open Division and take third overall in the combined Duncan and Queens Series Grand Aggregate. Here are two of Seb’s targets, as electronically logged — 1000 yards on the left, 600 yards on the right. NOTE: In Australia, the maximum numerical ring points value is 6, not 10 as in North America. But the center-most ring does register “X” as here. The match included targets shot at 300, 500, 600, 900, and 1000 yards.
Bench Testing with SEB NEO-X Prototype — VERY Impressive
Our friend F-Class John recently received one of the very first NEO-X prototypes sent to North America. John assembled the impressive new rest and took it to the range for testing. John was very impressed with the new rest to say the least. He told us: “This really is state-of-the art. I’m very impressed with how it folds compactly for transport, yet is extremely stable, with a nice open platform in the rear.” John noted that the swivel top allows precise alignment with your targets, even if the rest is not positioned perfectly on the ground. That helps when a shooter needs to set up quickly at a new yardage during a match.
When testing with his 7mm F-Open rifle, John noted that the rest is very solid on the bench and does not bump or wobble. See his observations in this exclusive test video:
Commentary by F-Class John
Here’s my quick review after shooting off the NEO-X prototype a couple times. It’s AMAZINGLY STABLE. The way it unfolds not only makes for a wide and stable footprint, but it also leaves lots of room for the shooter to work with, while controlling the joystick.
Another cool thing is that you don’t, technically, even have to lock the bridge down. The bridge is 100% stable after moving it up or down and the lock is more academic than anything.
The swivel head is a feature people will have seen on other rests but the way you can shoose to leave it swiveled or locked down is great. This new NEO-X is going to change things, I have no doubt.
Unboxing SEB NE0-X Prototype
John noted: “The way the NEO-X folds up is amazing, perfect for transporting. It weighs under 20 pounds fully loaded with all parts, joystick, and control arm.”
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Here is the view from 9500 feet ASL. The SRS in 7mm Rem SAUM almost outran the Swarovski laser…
7mm RSAUM in a bolt-action bullpup? Yes it works. A talented shooter, who calls himself “ColdboreMiracle” in social media, has a Desert Tech SRS-A1 rifle chambered for the 7mm RSAUM, and it hammers. The 7mm Remington SAUM (Short Action Ultra Magnum) is popular with F-Open competition shooters. It can also work well for long-range hunting and tactical tasks. Learn more about the 7mm Remington SAUM in our 7mm Cartridge Guide.
ColdboreMiracle owns the SRS-A1 “covert” model, which has a shorter handguard than the standard SRS-A1 model shown below. Desert Tech now offers an SRS-A2 model which has an M-LOK handguard and some refinements to the chassis.
Here is a detailed video review of a Desert Tech SRS chambered in .308 Win. You can see a close-up of a 100-yard 5-shot group at time-mark 6:25:
Here is a review of the newer SRS-A2 Covert (shorter model), after 1000 rounds. The reviewer believe the SRS bullpup’s shorter length offers some advantages for precision shooters:
ColdboreMiracle says the bullpup design has many advantages: “The Stealth Recon Scout (SRS) rifle from Desert Tech is a bullpup-configured precision rifle with a shorter length than many carbines. The SRS has a multitude of barrel options that can be swapped in under a minute — all of them come with a 1/2-MOA accuracy guarantee and return to zero. The SRS’s bullpup design puts the rifle’s COG closer to the shoulder, making the rifle balance better off-hand. The straight-line geometry of the SRS makes recoil seem lighter, and barrel hop is reduced, allowing the shooter to stay on target better. It takes a little getting used to, when converting from a traditionally-configured bolt gun. But once you do, you won’t go back.” To learn more about this rifle (and other Desert Tech arms), visit ColdboreMiracle’s Facebook Page and YouTube Channel.
The 7mm RSAUM — Why It Was Chosen for this SRS
ColdboreMiracle explains how he selected the 7mm Rem SAUM chambering for his Desert Tech SRS Bullpup: “I just did a comparison between barrel life, velocity, brass, etc. and came to the SAUM. I can tell you this, if you go with one for your SRS, make sure you use long bullets like the 183 or 195, and seat them long. That will aid in smooth cycling.”
Mr. ColdboreMiracle tested the new generation 183gr Sierra MatchKings (item # 1983). These impressive projectiles are “tipped” at the factory. Claimed G1 BC is a lofty 0.707 (at 2300 fps and above). We have heard other reports that these bullets “hold waterline” exceptionally well at 1000 yards. That indicates the bullet-to-bullet BC is very consistent. No doubt the factory uniforming/pointing of the bullet tips helps in that regard.
As you can see, these 183-grainers shoot well in ColdboreMiracle’s SRS rifle. Here are five shots at 100 yards. That’s very impressive for a tactical-style rifle shot from a field-type bipod.
ColdboreMiracle says: “This is the only reason I need to shoot Sierra bullets. On the right (above) you can see the results of the 183gr SMK from my 7mm SAUM. Five shots at 100. A huge thanks to Mark at Short Action Customs, LLC for [chambering this barrel] for my Desert Tech SRS.”
7mm Remington SAUM — Key Considerations
In some respects, the 7mm SAUM cartridge may be better than the 7mm WSM. The 7mm SAUM holds less powder — but that’s a good thing, since the capacity is more than adequate to do the job. You can drive the 180s at 3000 fps with a SAUM using less powder than with a WSM. Additionally, the SAUM case has a slightly longer neck. This gives you greater flexibility in bullet seating. With a long neck you can set the throat so the long 180+ graing bullets are above the neck shoulder junction, yet you can still seat shorter hunting bullets close to the lands. Additionally, long case necks, some believe, cause less throat erosion than shorter necks. That’s not “hard science” but it is certainly a view shared by many experienced shooters. The long neck is one reason many varminters favor the 6mm Remington over the .243 Winchester.
7mm RSAUM Is More Efficient than 7mm WSM
7mm RSAUM shooter Steven Ikeeda tells us: “I decided that some type of 7mm was the ticket for doing well at 1000-yard matches, especially if one could drive the high-BC bullets at 2900+ fps. Looking over various 7mm cartridges that could produce those velocities (and didn’t require case-forming), I was impressed by the 7mm SAUM and the 7mm WSM. According to the load manuals, the 7mm WSM offered a bit more velocity than the 7mm SAUM. However, to achieve its small velocity advantage, the larger 7mm WSM had to burn 7-10% more powder than the 7mm SAUM. (The 7mm WSM has 81.0 grains of capacity vs. 73.6 grains for the 7mm SAUM.) The SAUM is a very efficient case. It looks like a 6.5×47 Lapua on steroids.”
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There are hundreds of cartridge types capable of winning in F-Open. For F-TR you can shoot either the .223 Rem or .308 Win, but you have many load options. This article will focus on proven choices, currently used by the top F-Class shooters in the world. Our discussion will analyze cartridge selection based on the four different F-Class sub-disciplines: Open Mid-Range, Open Long-Range, F-TR Mid-Range, and F-TR Long Range.
Click image to view full-screen photo.
Mid-Range F-Open Cartridges
For starters, a .300 WSM is certainly capable of winning mid-range matches but it is not ideal. So what is ideal, and why? F-Class Mid-Range matches usually are usually shot at 300, 500, or 600 yards — or all three. At those distances the 6mm and 6.5mm cartridges rule. In moderate conditions, the 6mm Dasher is unbeatable. Its low recoil along with its super grouping ability and good ballistics make it my number one choice for Mid-Range.
Best bullets for the 6mm Dasher are: Vapor Trail 103gr, Berger 105 Hybrid, 108 BT, and 105 VLD (hunting). Best powders are: Varget, H4895, and Reloder 15.
Choices for Mid-Range in Tougher Conditions:
We all know that conditions are not always “moderate” that’s why something a little bit bigger will save you a “Nine” or two. The 6.5X47 Lapua was designed for 300-meter competition, but as soon as it was released, it was adopted by F-Class, benchrest, and tactical shooters. It offers great ballistics with very low recoil and big “accuracy window”. Lapua makes great brass for it (no surprise there) and Berger makes great bullets: 130gr VLD, 140gr VLD, 140gr Hybrids. Best powders in most barrels are Varget and H4350, I don’t use double-based powders such as Reloder 17 and the Vihtavuori N500 series because of their unpredictable performance day to day (greater temp sensitivity).
The 6.5X47 Lapua necked down to 6mm is also a great option for mid range matches. I was able to easily get 3200 fps with 105 hybrids and H4350.
Choice for Long-Range F-Open Competition
In Long-Range F-Open Class (out to 1000 yards), the big, high-BC bullets rule. If I had to pick one cartridge for F-Class (both mid- and long-range) I would pick the .284 Winchester or one of its variants. The .284 Win is currently dominating in F-Open competition. It offers great barrel life, it is super-easy to tune and its recoil is very manageable. The best bullets for it by far (in my opinion), are the Berger 180 Hybrids. But Sierra’s new 183gr MK bullet (with factory-uniformed meplats) seems to perform very well as does the Berger 180 VLD. Best powders for the .284 Win are H4350 and H4831SC.
Long-Range Only F-Open Cartridge
As much as I like the .284 Win, for long-range competitions I like the .300 WSM even more. If you look at a .300 WSM and a 6mm Dasher side by side, they appear almost identical in geometry — the .300 WSM looks like an “super-sized” Dasher. Both cartridges are currently the “darlings” of long-range benchrest due to their extraordinary grouping ability and huge “node’’ windows. Big accuracy windows allow loads to perform well in different conditions and geographical locations. That’s obviously very important if you travel to compete. The .300 WSM loaded with Berger 215gr or 230gr Hybrids is very tough to beat at long range, and it is currently my number one choice.
The 7mm RSAUM is another outstanding long-range round. It resembles a 6BR on steroids and it is almost as easy to tune. Best bullets for it are Berger 180gr Hybrids, 195gr EOLs, and Sierra’s 183gr MatchKing. Best powders for the 7mm RSAUM are: H4350, H4831SC, and VV N160.
Top Caliber/Bullet Combos for F-TR
In F-TR competition, the choice is clear — a .308 Win throated for Berger 185gr BTLRs and 200gr Hybrids will win in mid-range AND long-range comps. Many championships have been won, and many records set with those two bullets in the .308 Win. To quote Danny Biggs (a two times FTR National Champion) “The 185 BTLR is the best bullet for .308 Win ever made”.
The Berger 215gr Hybrids have been used to win many competitions including recently the 2015 F-Class Nationals. Bryan Litz won both the Mid-Range and Long-Range 2015 Championships using 215s. Bryan’s rifle is shown below:
I recommend chambers throated for the 185/200 grain projectiles over the 215/230 grain bullets. The reason is that if you have your barrel throated out for the 215s or the 230s, you could have a “slow” barrel and max out on pressure before the desired velocity is reached. Optimum freebore for the 230s is too long for the 185/200s, so you would be limited to using only 215/230gr bullets in that barrel.Furthermore, the recoil increase with heavier bullets is substantial, causing the rifle to be more difficult to shoot.
.223 Rem — Not A Competitive Option
I would stay away from the .223 Remington. On paper the 90gr VLD will shoot inside most .308 Win loads even at a 1000 yards. But in reality, on average, the .223 Rem, regardless of what powder/bullet combo is used, cannot compete with the .308 Win. [Editor: The equipment lists at major F-TR matches will confirm Kovan’s conclusion here.]
Conclusion (and Other Options)
This article covers only the (currently) most popular cartridge/bullet combos for F-Class (F-Open and F-TR). As I said in the beginning, many cartridge types are capable of winning but are not listed due to their low popularity, case design, or lack of quality components. All of the above information is based on my personal experience and it is meant to help new shooters choose the right cartridges for F-Class matches. Thanks for reading and good luck — Emil Kovan
Emil Kovan Competition History:
– 2014 F-Class Open National Champion
– 2015 F-Class Open National Championship, Silver Medal
– F-Class Open National Championship Teams, 2015, 2014, 2013, Shooting Team Member
– Over 15 wins in Regional and State Championships in Palma, F-TR, F-Open
– 2013 U.S. National Team Member
– 2017 U.S. National Development Team Member
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“A big congratulations to Bob Mead (1582-68X), who utterly destroyed the competition in tricky wind conditions to take the Gold.” — Jay Christopherson, 2017 F-Open Nationals Second Place.
In this 15-minute video, Team Lapua’s Erik Cortina interviews Robert Mead, the 2017 LR F-Open Champion. Robert (Bob) discusses his wind reading techniques with Erik, and the newly-crowned F-Open Champ explains how to set up a reliable wind zero. Bob also discusses cartridge choices in F-Open. He admits the straight .284 may be the tightest grouping 7mm cartridge, but he has used the 7mm RSAUM for a decade now. He believes the RSAUM may the best cartridge for 1,000 yards in 7mm, all things considered (grouping ability, ballistics): “To me it’s a light magnum, it’s capable of high speed, yet burns less powder than your regular magnums. [But] it’s a finicky cartridge — you’ve got to do a fair amount of load development.”
Every serious F-Class competitor should watch this video start to finish:
Credit Erik Cortina for video and the photo of Robert Mead with trophy above.
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Here is the view from 9500 feet ASL. The SRS in 7mm Rem SAUM almost outran the Swarovski laser…
7mm RSAUM in a bolt-action bullpup? Yes it works. A talented shooter, who calls himself “ColdboreMiracle” in social media, has a Desert Tech SRS bullpup rifle chambered for the 7mm SAUM, and it hammers. The 7mm Remington SAUM (Short Action Ultra Magnum) is popular with F-Open competition shooters. It can also work well for long-range hunting and tactical tasks. Learn more about the 7mm Remington SAUM in our 7mm Cartridge Guide.
ColdboreMiracle explains how he selected the 7mm Rem SAUM chambering for his Desert Tech SRS Bullpup: “I just did a comparison between barrel life, velocity, brass, etc. and came to the SAUM. I can tell you this, if you go with one for your SRS, make sure you use long bullets like the 183 or 195, and seat them long. That will aid in smooth cycling.”
Mr. ColdboreMiracle tested the new generation 183gr Sierra MatchKings (item # 1983). These impressive projectiles are “tipped” at the factory. Claimed G1 BC is a lofty 0.707 (at 2300 fps and above). We have heard other reports that these bullets “hold waterline” exceptionally well at 1000 yards. That indicates the bullet-to-bullet BC is very consistent. No doubt the factory uniforming/pointing of the bullet tips helps in that regard.
As you can see, these 183-grainers shoot well in ColdboreMiracle’s SRS rifle. Here are five shots at 100 yards. That’s very impressive for a tactical-style rifle shot from a field-type bipod.
ColdboreMiracle says: “This is the only reason I need to shoot Sierra bullets. On the right (above) you can see the results of the 183gr SMK from my 7mm SAUM. Five shots at 100. A huge thanks to Mark at Short Action Customs, LLC for [chambering this barrel] for my Desert Tech SRS.”
ColdboreMiracle says the bullpup design has many advantages: “The Stealth Recon Scout (SRS) rifle from Desert Tech is a bullpup-configured precision rifle with a shorter length than many carbines. The SRS has a multitude of barrel options that can be swapped in under a minute — all of them come with a 1/2-MOA accuracy guarantee and return to zero. The SRS’s bullpup design puts the rifle’s COG closer to the shoulder, making the rifle balance better off-hand. The straight-line geometry of the SRS makes recoil seem lighter, and barrel hop is reduced, allowing the shooter to stay on target better. It takes a little getting used to, when converting from a traditionally-configured bolt gun. But once you do, you won’t go back.” To learn more about this rifle (and other Desert Tech arms), visit ColdboreMiracle’s Facebook Page and YouTube Channel.
7mm Remington SAUM — Key Considerations
In some respects, the 7mm SAUM cartridge may be better than the 7mm WSM. The 7mm SAUM holds less powder — but that’s a good thing, since the capacity is more than adequate to do the job. You can drive the 180s at 3000 fps with a SAUM using less powder than with a WSM. Additionally, the SAUM case has a slightly longer neck. This gives you greater flexibility in bullet seating. With a long neck you can set the throat so the long 180+ graing bullets are above the neck shoulder junction, yet you can still seat shorter hunting bullets close to the lands. Additionally, long case necks, some believe, cause less throat erosion than shorter necks. That’s not “hard science” but it is certainly a view shared by many experienced shooters. The long neck is one reason many varminters favor the 6mm Remington over the .243 Winchester.
7mm RSAUM Is More Efficient than 7mm WSM
7mm RSAUM shooter Steven Ikeeda tells us: “I decided that some type of 7mm was the ticket for doing well at 1000-yard matches, especially if one could drive the high-BC bullets at 2900+ fps. Looking over various 7mm cartridges that could produce those velocities (and didn’t require case-forming), I was impressed by the 7mm SAUM and the 7mm WSM. According to the load manuals, the 7mm WSM offered a bit more velocity than the 7mm SAUM. However, to achieve its small velocity advantage, the larger 7mm WSM had to burn 7-10% more powder than the 7mm SAUM. (The 7mm WSM has 81.0 grains of capacity vs. 73.6 grains for the 7mm SAUM.) The SAUM is a very efficient case. It looks like a 6.5×47 Lapua on steroids.”
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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
Each week, the U.S. Army Marksmanship Unit (USAMU) publishes a reloading article on its Facebook Page. In this week’s 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 careful] 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
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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Forum member Mark Dalzell (aka “MDSlammer”) is an avid long-range shooter and talented movie-maker. Some months ago, he produced a great video about shooting his Savage 110 BA at 1200 yards. That video was a hit with readers, and now Mark has come up with a new video, with the range pushed out to 2300 yards (that’s 1.3 miles!). Mark and his compatriots Dale Jorgensen and Gio Valdez headed out to their “secret spot” in the high desert, near Jean, Nevada, armed with a pair of 7mm RSAUMs and Mark’s .338 Lapua Magnum Savage 110 BA. Given the degree of difficulty, it’s not surprising that Mark’s gang had more misses than hits this time out, but they did produce an entertaining video that shows the challenges of shooting at Extreme Long Range.
Watch HD Video — Extreme Long-Range Shooting at 2300 Yards
Shooting 2300 Yards with the 7mm RSAUM and .338 Lapua Magnum
Target Cam Spotter: Wally Krusee
Film By Mark Dalzell – Sin City Productions / All Rights Reserved, Copyright 2012
Mark was shooting a Savage 110 BA .338 Lapua Magnum, the same gun he used for his previous 1200-yard high desert shooting safari. The elevation required to get on target at 2300 yards was mind-boggling. Elevation for Mark’s .338 LM was 96.5 MOA (on top of a +40MOA rail). Mark’s buddy Dale was running a full 30.5 MILs of elevation with his 7mm RSAUM with milrad optic.
Mark set up a wireless remote camera near the target, so you can see where the shots impacted. A second camera was behind the trigger-pullers, giving a “shooters’-eye view”. The target was a full-sized steel silhouette with an orange square painted in the middle.
Mark reports: “I was out this past Monday with a couple of buddies. We tried our luck shooting at 2300 yards. I had one hit out of 30. Very poor marksmanship. But I did learn a few things about shooting at this distance for the next time. I have nothing but admiration for those shooters who are consistent at this distance. [It was] pretty amazing.”
Equipment List and Load Specifications
Mark Dalzell
Dale Jorgensen
Gio Valdez
Savage BA110 .338 Lapua Magnum Murphy +40MOA Titanium Rail Harris bipod Nightforce 5.5-22x50mm NXS Speed Turret
7mm RSAUM Krieger 30″, 1:8.75″ twist Barrel with Ross Brake McRees Folder Chassis Harris Bipod Bushnell HDMR Scope
7mm RSAUM Krieger 28″, 1:9″ twist 5R Barrel with Ross Brake McRees Folder Chassis GG&G Bipod Bushnell H2DMR Scope
At the U.S. Armed Forces Interservice Championships held earlier this month in Quantico, Virginia, USAMU Team Praslick set a new 1000-yard Team Record, with a spectacular 1197-68X score, beating the existing 1192-66X record set way back in 1997. The course of fire was 20 shots by each of six shooters, 120 shots total. This record was doubly impressive because it involved mandatory paired firing. The squad was divided into three pairs. When each pair went to the firing line, the two shooters would alternate shots. Team Coach, SFC Emil Praslick, had to make a wind call for one shooter, and then the other, shot by shot — that’s not easy. The record-setting squad was an all-star contingent of USAMU shooters: SGT Sherri Gallagher, SPC Amanda Elsenboss, CPL Matt Rawlings, SSG Shane Barnhardt, SSG Brandon Green, SSG Ty Cooper. Praslick said he was “very proud of my shooters.”
The 1197-68X record was set in “Any Sights / Any Rifle” competition using bolt guns chambered for the 7mm Remington Short-Action Ultra-Magnum (RSAUM), and fitted with Nightforce scopes. Coach Praslick says the USAMU is very pleased with the performance of the 7mm RSAUM: “Our 7mms can deliver very tight vertical spreads at 1000 yards.” Praslick also praised the work of USAMU armorers who build the rifles and load the ammo for USAMU teams: “We’ve got world-class gunsmiths. That’s our advantage. All the guns are tested at distance with match ammunition. We can count on the guns and the ammo to perform shot after shot. This is a big confidence builder for our USAMU shooters.”
New 1K Service Rifle Record
Along with the great performance by USAMU Team Praslick, USAMU Service Rifle shooters coached by SFC Jeremy Mangione set a new Service Rifle record. Using .308-Caliber AR10-type rifles with 185gr Berger bullets, the Team posted a 1154-33X Aggregate, a Service Rifle Team Record. That’s amazing considering these shooters were aiming with military-style iron sights with a post front sight. One of the squad’s shooters, SPC Augustus Dunfey, recorded a 200-10X. Coach Praslick called this a “spectacular individual performance”. Praslick told us that Dunfey’s 200-10X “is definitely the highest [20-shot] Service Rifle score shot in Interservice 1000-yard competition. And, as far as anyone can remember, it is the highest [20-shot] 1000-yard score ever shot with a Service Rifle anywhere.” SPC Dunfey was shooting at a target with a 20″ 10-Ring, and 10″ X-Ring. This means, using a stout-recoiling .308 rifle with sling (no rest) and relatively crude sights, Dunfey put half his shots inside one MOA and did not drop a single point. That’s impressive….
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Over the past couple of weeks, State Long-Range Championships were held in California and Arizona. Many of the best shooters in the Western States were in attendance. In both CA and AZ, State titles were awarded in both High Power and F-Class disciplines.
California State Long-Range Championship, November 6-7, 2010
On November 6th and 7th, the California Long-Range Championship was hosted at the Coalinga Range. In the High Power division, Trevor Hengehold shot a brilliant match to finish first, and win the Championship, with a 795-36X score. Jim O’Connell was second with 783-37X which also earned him the High Senior Title. Dennis Flaherty had the next highest score (779-30X), and just two points behind Dennis was Gary Eliseo with 777-24X.
In the F-Class Division, Jerry Tierney, shooting his new 7mm RSAUM, won the championship with a 790-36X Score. Hot-shooting Brenda Hill took second with 780-31X, and Peter White was third with 773-19X. Though he had almost no time to practice with his RSAUM prior to the match (it was chambered the weekend before), Jerry was delighted with the gun’s performance: “This is the most accurate long-range rifle I’ve ever shot. And that’s saying a lot. I did get some load development help from Danny Biggs, who uses the same cartridge.” Jerry was shooting the new 7mm Berger 180gr “hybrid” bullets, with sorted Remington RSAUM brass, CCI BR2 primers, and Hodgdon H4831sc powder. The bullets were seated about 0.015″ off the lands and Jerry told us his load was running “real close to 3,000 fps”.
Jim O’Connell Reports: “Congratulations to Trevor Hengehold and Jerry Tierney, the two new State Champions (High Power and F-Class). Trevor started out in front and never looked back. Jerry posted some good scores on Sunday to come from behind for his victory. This was the last of the Big Coalinga matches for 2010. We get started early in 2011 with the State Fullbore Match in February (26-27) and the State Palma Match in March (5-6). We are planning on awarding F-Class titles at all the State prone Championships (Fullbore, Palma, and Long Range) in 2011.”
Arizona Long-Range Championship, November 20-21, 2010
At the Ben Avery Shooting Facility outside Phoenix, many of the best shooters in the Western states congregated last weekend for the season-ending Arizona Long-Range Championship. Conditions were challenging but the top competitors managed to master the switchy winds and post high scores. In the High Power Division, the match winner and new AZ State Champion is Rick Curtis. Congrats to Rick! Curtis finished with an impressive 986-45X Grand Agg, after posting a 591-24X Iron Sights Agg, and a 395-21X “Any Sights” Agg. Eddie Newman, the High Senior for the match, posted the next highest Aggregate score, a 985-37X. Phil Hayes also shot a 985 but with 34Xs. Middleton Tompkins followed Hayes with a 979-36X. Peter Church was next with a 974-43X (second highest X-Count), and our Contributing Editor German Salazar finished with 973-34X.
In the F-Class Division, twenty-one shooters vied for honors. In F-Open, Texan Erik Cortina won the Championship with an impressive 972-17X. Charles Gooding was close behind with a 970-27X. Charles had high X-Count among all F-Class shooters. Freddy Haltom, shooting as a “Expert” had the third-highest score, an impressive 962-25X. Next in line was Tony Mangold with 944-19X.
F-Open Champ Cortina offered this report: “I was able to pull it off last weekend and win the Arizona State LR F-Open Championship at Ben Avery. The winds were strong and switching, making it very challenging! We ended up shooting 5×1000 instead of 6×1000 as scheduled. On Sunday, we only shot two strings as the third was canceled because of rain. I was shooting my .284 Shehane with 180gr Berger VLD bullets. My winning gun is a switch barrel 6.5×47 Lapua / .284 Shehane built by Mark Pharr of Tumbleweeds Custom Rifles. This Lawton 7500-actioned gun is the same rifle I used to set Club Records at the Bayou Rifle Club in Houston: 600-49X at 300 yards, and 595-34X at 1000 yards.”
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In some respects, the 7mm SAUM cartridge may be better than the 7mm WSM. The 7mm SAUM holds less powder — but that’s a good thing, since the capacity is more than adequate to do the job. You can drive the 180s at 3000 fps with a SAUM using less powder than with a WSM. Additionally, the SAUM case has a slightly longer neck. This gives you greater flexibility in bullet seating. With a long neck you can set the throat so the long 180+ graing bullets are above the neck shoulder junction, yet you can still seat shorter hunting bullets close to the lands. Additionally, long case necks, some believe, cause less throat erosion than shorter necks. That’s not “hard science” but it is certainly a view shared by many experienced shooters. The long neck is one reason many varminters favor the 6mm Remington over the .243 Winchester.
.223 Rem — Not A Competitive Option
Emil Kovan Competition History:
Mark was shooting a Savage 110 BA .338 Lapua Magnum, the same gun he used for his previous 1200-yard high desert shooting safari. The elevation required to get on target at 2300 yards was mind-boggling. Elevation for Mark’s .338 LM was 96.5 MOA (on top of a +40MOA rail). Mark’s buddy Dale was running a full 30.5 MILs of elevation with his 7mm RSAUM with milrad optic.
In the F-Class Division, twenty-one shooters vied for honors. In F-Open, Texan Erik Cortina won the Championship with an impressive 972-17X. Charles Gooding was close behind with a 970-27X. Charles had high X-Count among all F-Class shooters. Freddy Haltom, shooting as a “Expert” had the third-highest score, an impressive 962-25X. Next in line was Tony Mangold with 944-19X. 
