SunDay Gunday: Seb’s 7 FCP F-Open Rifle with Borden Action

NOTE: We are sad to announce that, a week ago, Jim Borden passed away from cancer. Jim, who founded and operated Borden Accuracy, was a great shooter as well as a designer/builder of superb actions and complete rifles.

Jim won 11 National Benchest Championships, was a Benchrest Hall of Fame member, and served six terms as President of the International Benchrest Shooters (IBS). Today’s featured rifle features the outstanding Borden BRMXD action that Jim designed and crafted.

2026 F-Class National Championships Coming Soon to Ben Avery
The 2026 National F-Class Mid-Range and Long Range Championships will be held later this month at the Ben Avery Shooting Facility, in Phoenix, Arizona.

F-Class Mid-Range National Championship: October 25-28
F-Class Long Range National Championship: October 29 – November 1
Program & Registration: www.desertsharpshooters.com/2026-f-class-nationals

To help mark this event, today’s Sunday GunDay story features an American-crafted F-Open rifle campaigned by Sebastian (“Seb”) Lambang at the USA F-Class Nationals in 2023. Seb, the brilliant creator of SEB rests, joystick bipods, and rear bags, competed at the 2023 NRA F-Class National Championships, also held at Ben Avery. For that 2023 event, Seb commissioned a handsome, state-of-the-art F-Open rifle built by Blake Barrel and Rifle. Above is Seb’s F-Open rifle on the firing line at Ben Avery.

Seb Lambang’s impressive 7 FCP rig is chambered for the 7 FCP cartridge, an “improved” 6.5 PRC necked up to 7mm. This handsome rifle was crafted by Blake Barrel and Rifle using a 7mm, 1:8.5″-twist Blake barrel chambered in 7 FCP fitted to a Borden Accuracy BRMXD action. Mated to the Borden action is a Bix’N Andy Competition Benchrest trigger. On top is a March 10-60x56mm HM scope.

The handsome laminated wood XR stock is made by Cerus Rifleworks. The XR stock boasts a R.A.D. recoil reduction system in the rear, and a metal bag-rider system at the forward end of the stock. The rig employs an adjustable F-Class Products F-Open Barrel Tuner.

Seb Lambang is a talented shooter as well as a great craftsman. On the side of his March X scope it states: “Sebastian Lambang, QRA Queens 2022, F-Open Winner”.

To see more images of this rifle, visit Seb Lambang’s Facebook Page.

Sebastian Lambang — Founder and Chief Designer of SEB Rests
When he is not competing, Seb works hard producing SEB Front Rests, SEB Neo-X Rests, SEB Mini-X tripod rests, and the class-leading SEB JoyPod-X joystick bipod, favored by F-TR shooters worldwide. Here are products at Seb’s warehouse, getting ready to be shipped out.

About the 7 FCP — New 7mm Cartridge Derived from 6.5 PRC

The 7 FCP was a cartridge designed from the ground up by F-Class Products out of Phoenix, Arizona in the fall of 2022. The developers believe it is the “ultimate cartridge” for the F-Class Open Division competition. F-Class Products notes: “We wanted a cartridge that [had] an efficient case capacity [matching] the 7mm Remington Short Action Ultra Magnum. The 7 RSAUM has proven to be the most winning cartridge in world F-Class competitions and many nationals and finale events. The problem with the RSAUM is brass availability. Remington stopped making brass for the RSAUM years ago and recently Norma has also stopped producing brass for it. The only option now is ADG. While the ADG brand of brass is good, it is quite expensive and also is only run in short runs and is hardly ever available.”

So the 7 FCP was developed from the 6.5 PRC, which has high-quality Lapua brass available. The 7 FCP was designed to shoot the 180 grain Berger Hybrid bullet at 2960 FPS out of a 30″ barrel without excessive pressure. SEE: 7 FCP Cartridge INFO FAQ Page.

7 FCP Cartridge — Wildcat Based on 6.5 PRC Necked up to 7mm

How Does the 7 FCP’s Case Capacity Compare?
F-Class Products states: “The parent case of the 7 FCP is a 6.5 PRC. The 6.5 PRC is a magnum case that has a head diameter of 0.532″ and has a overall length of 2.020″. It is the same overall length as the 7 RSAUM but with a smaller diameter body. Hence, without improving it, you will get not get the case capacity of a 7 RSAUM case, and therefore you will not get the velocities that the 7 RSAUM produces either.” F-Class Products has compared the capacity of cases commonly used in F-Open competition:

.284 Winchester = 63 grains of water capacity
.284 Shehane = 66.5 grains of water capacity
6.5 PRC = 65 grains of water capacity
7-6.5 PRC = 66.5 grains of water capacity

As you can see by the data above, the 6.5 PRC that is simply necked up to a 7mm does not provide more case capacity than the .284 Shehane. That is why the PRC has the shoulder moved forward.

What Powders Work Well in the 7mm FCP?
F-Class Products has tested many powders with the 7 FCP: “Any powders that work well in a .284 Win, a .284 variant or a 7 RSAUM and/or variant, can work well in the 7 FCP. We have tested many different powders and many show to work excellent. Here is a list of the powders we have tested that work well in our testing and in our customers’ testing:

This is just a short list of what we believe are the core powders that will burn and work efficiently in the 7 FCP. There are plenty of other powders that also can work, yet they may be temperature sensitive and or not burn efficiently in the case.”

What Velocities Are Optimal?
F-Class products observes: “With the 180 grain Berger bullet we see accuracy from 2920-2980 FPS muzzle velocity. With the 190 grain Hornady A-Tip bullet we see accuracy from 2860-2900 FPS.”

What Twist Rates Do You Recommmend?
F-Class Products recommends a 1:8.5″-twist barrel. An 8-twist can work, yet the accuracy nodes may be narrower than the 8.5 twist. A 9-twist barrel can also work if you are shooting a 184 grain bullet or less. These twist rates are recommended for lead cored bullets. If you are planning on shooting a solid copper bullet, consult the bullet manufacture for recommended twist rates for that particular bullet.

What Is the Parent Case?
The parent case of the 7 FCP is a 6.5 PRC. The 6.5 PRC is a magnum case that has a head diameter of 0.532″ and has a overall length of 2.020″. It is the same overall length as the 7 RSAUM but with a smaller diameter body, hence without improving it, you will get not get the case capacity of a 7 RSAUM case, and therefore you will not get the velocities that the 7 RSAUM produces either.