On the modern battlefield sniper rifles, once the domain of 7.62mm NATO, have become larger and larger caliber affairs. From the .300 WinMag of the 90s to the .338 Lapua today, sniper rifles strike at distances rarely reached in combat, except on a few extraordinary occasions.
However, the larger caliber rifles chambered in .50 caliber, like the versions of the Barrett M82, have much in common with a class of rifle that saw its brief heyday in the first half of the last century.
Today, shoulder aimed bolt or semi-automatic rifles of 12mm or larger are dubbed anti-material rifles. But in the inter-war years, they were known as anti-tank rifles, exemplified by the .55 caliber British Boys and 14.5mm Soviet PTRS-41. However, in Finland a rifle trumped them all in the form of the Lahti 20mm L-39.
When you look at the Lahti it seems out of proportion next to a man. It is massive in weight and length. Tipping the scales at 100 pounds and nearly eight feet long, to call the Lahti portable was a stretch. But its strength was in its caliber, 20mm with a muzzle velocity of 2,600 ft/s.
And while that caliber and velocity were impressive, it could not live up to its anti-tank name. With tank armor making immense strides since World War I, a man-portable anti-tank rifle was hopelessly optimistic. And yet, nations like Finland, Germany, Soviet Union and Great Britain invested in large caliber rifles.
The Lahti first saw service against the Soviets in the Winter War. And while Soviet T-34s could shrug off the 20mm rounds, the L-39 could decimate soft skinned vehicles, bunkers and stationary aircraft at long ranges; and harass the enemy at even longer ranges. The effective range of the 20mm Lahti was one kilometer.
Generally towed on a pair of bipod skis, often by reindeer, the L-39 was served by two men. Interestingly, a similar Imperial Japanese 20mm anti-tank gun was broken down during transport and crewed by as many as five men. The Finnish handled the punishing recoiling gun, topped by its 10-round box magazine which fed a gas-operated semi-automatic action, via a harmonica-style muzzle break. The L-39s Armor Piercing rounds could punch through 30mm of armor at 100 meters, with a variety of other rounds run through the weapon nicknamed by the Finns Norupyssy
, Elephant Gun.
While a closed bolt rifle, where the bolt cycles under the power of burning propellant gas and goes right back into battery, the Lahti L-39 is a kind of hybrid both closed & open bolt. To allow the rifle barrel to cool between shots, the L-39s bolt locked in the open position only to be released by a lever in the grip below the trigger assembly.
The legacy of rifles like the L-39 lives on with very special anti-material rifles like the South African manufactured NTW-20 and Croat single shot RT-20, 20mm anti-material rifle. But the Finns can claim audacity in the name of practicality of defense.