TsKIB SOO MTs-343 Rifle Chambered in .300 Lapua Magnum [Arms & Hunting 2017]

Hrachya H
by Hrachya H

Earlier we had reported about the introduction of this rifle (MTs-343). TsKIB SOO has shown it again in the Arms & Hunting 2017 exhibition. We had a chance to talk to the designer and take some detailed pictures.

The MTs-343 is a competition rifle design for F-Class Open division. It is a single shot rifle chambered in .300 Lapua Magnum. The rifle features a “barrel block” bedding system where the barrel is clamped in the handguard and the receiver itself is free floated. The company officials told us that unlike the competitors, the clamped barrel portion of their rifle is much longer. They found that the longer clamping surface increases the accuracy.

Note the gap between the receiver and stock. The receiver is basically free floated.

Right where the handguard ends the barrel diameter increases. The thicker short portion of the barrel protruding over the handguard is less affected by the vibration. Also, the barrel/handguard contact point is the recoil shoulder which does the work of the recoil lug of traditional bolt action rifles.

Because of the barrel block layout, the handguard becomes the most stable platform in relation to the barrel. That’s why the Picatinny rail section for the scope is on the handguard extension rather than on the receiver.

This bedding system is good for competition shooting where the weight of the firearm is not something to be concerned about. It is less desirable for the military and tactical use because the higher accuracy is accomplished with the heavier action. MTs-343 weighs 10 kilograms (22 lbs). The barrel length is 800 mm (31.5″). It is advertised to have a sub 1/2 MOA accuracy.

The rifle has a 3-lug bolt and a plunger ejector

The company is still experimenting with the length of the clamped barrel to find the most efficient length that will provide the most accurate results.

Hrachya H
Hrachya H

Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at Hrachya@TheFirearmBlog.com

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  • Jonp Jonp on Oct 18, 2017

    Free floating the receiver instead of bedding it. That's interesting.

  • Mike N. Mike N. on Oct 18, 2017

    I shoot F-class (F-open). This is the (all too common) casa of someone chasing ballistics over everything else. I used to do that, running the highest velocities I could safely extract... when I backed down 100fps my scores noticeably improved.

    Lots of shooters find that a .300WSM shooting a Berger 230 grain bullet around 2850fps is too much, and that they do better with the 215 grain bullet just from the easier gun handling (you wouldn’t think so considering F-open guns are shot off front rests and rear bags in the prone position, but gun handling is critically important).

    Plus I can’t imagine what kind of barrel life you’d get. Shot in competition conditions, .300WSMs get around 1200-1500 rounds barrel life, while 7mm short mags and 6.5x284 typically get under 1000 rounds. With a .300 Lapua Mag., I bet by the time you finish doing load development and the barrel settles down it’s time for a new barrel.

    Finally, I’ve seen someone shoot .338 Lapua MAg at an F-class match. You could see the recoil ripple though his body, since you are not allowed to use a brake or suppressor.

    That’s why .284 Win. and derivatives are so popular in F-open, and why most people who finish in the top10 at major matches shoot them, a good combination of accuracy, ballistics, recoil, and barrel life.

    • Kaban Kaban on Oct 19, 2017

      @Mike N. The reason for choosing ".300 LM" is probably called STs-154 (СЦ-154). It is name assigned to .300 LM (along with STs-152 for .338 LM) so prototype military weapons could be chambered for them.

      I agree that the cartridge is seriously overbore; one of select few .300s that beats .300 RUM. Though it could be probably be "dialed back" to a degree, too.