The Japanese Agency for Technology and Logistics for Takeovers (ATLA) has conducted a test firing of a modern naval railgun.
Today it is known that Japan has a railgun capable of handling projectiles weighing approximately 0.71 pounds. The energy used for its launch is at the level of 5 MJ, although in the future it is to be increased to 20 MJ, which will contribute to increasing efficiency (projectile speed and range).
For more, check out this essanews/MSN story.