August 31st, 2016

Anatomy of the Modern F-Open Rifle

.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

Emil Kovan is one of the top F-Class shooters in the world. He won the 2014 United States F-Open Championship. Earlier this month Emil finished second in F-Open Division at the 2016 Canadian National F-Class Championship in Ontario. Emil actually tied Open-class winner Shiraz Balolia for overall score AND “V”-count, but Emil was awarded second on the tie-breaker.

The Anatomy of a Modern F-Class Open Rifle

Report by Emil Kovan
Kovan Match Rifles LLC, www.matchrifles.com

“What are the best components for an F-Open class rifle, and why?” That’s a question that I get asked all the time and will try to answer in this article. Two months ago, I was contacted by Duane, a gentleman I met at the 2015 F-Class Nationals. He was interested in building a rifle with the new Master Class Low Profile F-Open Stock, created by Carl Bernosky and Alex Sitman of Master Class Stocks.

I have known Alex Sitman for many years, and use his stocks exclusively, but was not very familiar with his new Low Profile F-Open stock. After a brief conversation with Alex, I placed an order, and had the stock inletted and bedded at my shop in a month. My first impression was “Wow that’s a long stock” — the forearm is significantly longer than on the original Master Class F-Class prone stock. I bolted the barreled action in, and squeezed the end of the forearm and barrel together, the stock flexed a little bit, but not as much as other designs that I have tested. I think that’s due to having “more meat” in the receiver area. The full stock depth continues farther forward that on some other “low profile” designs. That makes the stock stiffer in the vertical plane, reducing the hinging effect forward of the action. The stock was finished in gloss black per the customer’s request. Interestingly, I found that the multiple layers of paint and clearcoat stiffened the stock up quite a bit.

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.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

Low Center of Gravity Tames Torque
Compared to the original Master Class F-Open stock, the barrel sits about an inch lower. Lower center of gravity equals less torque, and that is very important when shooting heavy bullets in fast twist barrels. Another significant improvement is that the toe of the stock is flat and parallel to the forearm. I added a 3/4″ track rail in the rear, and milled the underside of the fore-end to create two parallel “rails” in the front to help the stock track better.

One of the biggest reasons why I like Master Class stocks, is the pistol grip. I don’t shoot “free recoil” and a comfortable pistol grip is super important to me when selecting a stock. The new Master Class Low Profile stock shares the same grip as the old model. This allows the stock to accommodate either a “hard hold” style or a more free-recoil style of shooting — whatever the rifle’s owner prefers. This design versatility is one reason I recommend Master Class stocks. Shooters may experiment with either shooting style to find what suits them best.

.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

Cartridge Choice — A 40° .284 Win Improved
Duane decided to have the barrel chambered for my 284 KMR IMP (Improved) wildcat. What is .284 KMR IMP and why choose it over the straight .284 Winchester? Improved by definition means “made better”, I took a great cartridge, and modified it to increase capacity, reduce pressure, and increase brass life.

There are many “improved” variants of the original .284 Winchester: 7mm Walker, .284 Shehane, .284 Ackley and so on. My version, the 284 KMR IMP, shares the .010″ blown-out sidewalls of the .284 Shehane, but I have further increased the case capacity by changing the shoulder angle from 35 to 40 degrees. The 284 KMR IMP allows you to almost match magnum cartridge velocity in a standard-bolt-face action. If you want to run 180gr-class 7mm bullets over 2900 FPS, it is cheaper and more convenient to have a barrel chambered in 284 KMR IMP than to spend $650 for a magnum bolt.

Tuning Loads for the .284 Win Improved Cartridges
The 284 KMR IMP seems to have two nodes, one around 2820 fps and other at 2940 fps. My match load clocks at 2935 fps with single-digit ES. Note –I selected that load based on accuracy, NOT raw speed. A lot of novice (or hard-headed) shooters make the mistake to push their cartridges to the max, and disregard more accurate loads at lower velocity.

.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

The sport of F-Class is rapidly growing, and the equipment used is improving constantly. I remember that only few years ago, an F-Open rifle that could shoot sub-one-inch of vertical at 300 yards was considered competitive. Now, we are pursuing sub-one-inch vertical at 600 yards! It takes a great rifle to approach that goal, but it is also up to the shooter to learn and experiment as much as possible in order to achieve success.

Dies for an Improved .284 Win Cartridge
One of the biggest challenges in campaigning a wildcat cartridge has been obtaining great dies. When searching for custom dies, it almost seems like that the odds are stacked against us. The most common problem is wait-time — custom die orders can take months to be completed. Also, most custom die makers want you to send them two or three cases, each fire-formed three times. I find that funny because if could somehow properly size the cases for three fire-forming cycles, I would not need a sizing die.

.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

Custom-made dies should size the case just right, but sometimes the die’s internal dimensions are slightly off, and this leads to problem number two: dies sizing too much (or even worse) too little. I had a one “custom” die that would not size the bottom of the case enough. This made the extraction of fired cases very difficult. I feel that the best option (if available) for shooters interested in wildcat chambers is to have their gunsmiths make the dies. I offer that die-making service in addition to barrel chambering.

BAT Machine “M” Action
Duane decided to use a BAT M action for this rifle, and I think that he could not have made a better choice. We are blessed with many good match-quality receivers: Barnard, BAT, Borden, Kelbly, Nesika, and Stiller just to mention a few. These are all very well-made and suitable for F-Class. Among BAT Machine Co.actions, I like BAT models M, MB, and 3LL best. I prefer these because because of their size (large bedding footprint) smoothness, timing, options available, and last but not least visual appearance.

Trigger: I recommend and use Jewell triggers. Other good options are: Kelbly, CG Jackson (good 2-Stage) Anschutz (best 2-Stage for Bat and Kelbly actions), Bix’N Andy, and David Tubb.

Barrel: Duane made another good choice here. He decided to go with a Brux 1:8.5″-twist, 4-groove cut-rifled barrel. If you look at the F-Class and Long Range benchrest equipment lists, you will see that cut-rifled barrels are currently dominating. Many records have been shot with both button-rifled, and cut-rifled barrels. I have shot both, and prefer cut-rifled barrels. I am not saying that button-rifled barrels are not capable of shooting as well as cut-rifled barrels, but on average, in my experience, four out of five cut-rifled barrels (from top makers) will shoot well, vs. three out of five buttoned barrels. YMMV, but this is what I’ve observed.

Brux Barrels is not the only company that produces very accurate cut-rifled barrels. We know that Krieger, Bartlein, Satern, and Hawk Hill Custom all make fine cut-rifled barrels as well.

Scope: Duane’s rifle was fitted with a Nightforce 15-55x52mm Competition scope with DDR-2 reticle. This optic is ultra clear, reasonably lightweight (28 oz.), super reliable, and has 1/8 MOA clicks — what you want for long range F-Class competition. In this 15-55X NF model, I like the DDR-2 reticle best, because fine cross hairs (FCH) are hard to see in heavy mirage. The DDR-2 has a heavier horizontal line, with a center dot. March scopes are also very popular and very well-made.

.284 Win F-Class F-Open Rifle Emil Kovan Brux BAT M Master Class Bernosky

Thanks for reading, and keep ‘em in the middle…

Emil Kovan F-Class competition bio photoEmil Kovan Competition History:

– 2014 F-Class Open National Champion

– 2016 F-Class Open Canadian Championship, Silver Medal (tied for first on score)

– 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

Permalink Bullets, Brass, Ammo, Competition, Gunsmithing 3 Comments »
May 23rd, 2014

Kelbly’s and GRS Introduce New Low-Profile F-Class Stock

Made in Norway by GRS, the new Kelbly “X-Eater” stock combines an ergonomic grip with the superior tracking ability of the latest, low-profile designs. Height-adjustable cheek-piece and length-adjustable buttpad allow the shooter to tailor the stock to his preferences. The ergonomic grip/wrist helps the shooter steer the rifle precisely with greater control. The low-profile design aids tracking and helps tame the torque generated by the large 7mm and .30-cal cartridges favored by top F-Open competitors.

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Kelbly Rifles GRS F-Class Stock X-Eater F-Open

Kelbly Rifles GRS F-Class Stock X-Eater F-Open

The fore-end is made with the same twin-runner (catamaran-style) design as the previous GRS F-Class Open stock. (On the underside of the fore-end there are left/right rails with a relieved area in the center). The big change is that this new stock sits lower on the front bag compared to the first F-Class stock from GRS. The rear of the stock is designed for a two-stitch rear bag. Initially the stock will only be offered in Right Hand versions in black/blue and red/blue laminate.

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Kelbly Rifles GRS F-Class Stock X-Eater F-Open

Kelbly Rifles GRS F-Class Stock X-Eater F-Open

    STOCK SPECIFICATIONS

  • Stratabond Laminate with lacquer finish
  • Adjustable Length of Pull (from 13.8 to 15.0 inches)
  • Height-Adjustable cheek-piece
  • Cushy 0.5″-thick Limbsaver/GRS recoil pad
  • Stock (by itself) weighs 4.07 pounds (with Rem 40X inlet)
  • Optional Height-Adjustable recoil pad.

Kelbly Rifles GRS F-Class Stock X-Eater F-Open

Permalink Gear Review, New Product 4 Comments »