By the end of World War II, jet aircraft had so increased the speed of attack that the Bofors simply could not get enough rounds into the air to counter the aircraft before it had already flown out of range. In order to effectively engage these threats, the gun would have to have longer range and a higher rate of fire, thereby increasing the number of rounds fired over the period of an engagement. Bofors considered either updating the 40 mm, or alternately making a much more powerful 57 mm design. In the end they did both.
The new 40 mm design used a larger 40 × 364R round firing a slightly lighter 870 g shell at a much higher 1,030 m/s (3,379 fps) muzzle velocity. The rate of fire was increased to 240 rounds per minute (4.0 rounds per second), similar to the German Flak 43. Additionally, the carriage was modified to be power-laid, the power being supplied by a generator placed on the front of the carriage. The first version was produced in 1947, accepted in 1948 as the "40 mm lvakan m/48", and entered Swedish service in 1951. Additional changes over the years have improved the firing rate first to 300 rpm (5.0 rounds per second), and later to 330 rpm (5.5 rps)Vehicle 90 (CV90)
Foreign sales started, as they had in the past, with the Netherlands and the United Kingdom. In November 1953 it was accepted as the NATO standard anti-aircraft gun, and was soon produced in the thousands. The L/70 was also used as the basis for a number of SPAAGs, including the U.S. Army's failed M247 Sergeant York. The UK's RAF Regiment adopted the L70 to replace its L60 guns in 1957, retiring its last examples in 1977 and replacing them with the Rapier system.
In 1970's Zastava Arms acquired from Bofors license to produce L/70 version together with laser-computer group. . Ammunition 40mm for L/70 is locally produced for domestic use and export in Sloboda Čačak
This example is inert and filled with a resin most likely used for training purposes still an impressive looking round that would look great in a display of ammunition.