M1299 is an American 155 mm tracked self-propelled howitzer currently under development.

The M1299 self-propelled howitzer is developed as part of the Extended Range Cannon Artillery program.

Designed as a self-propelled system with longer range and better rate of fire than the latest M109 model, the M109A7, the future M1299 SpH is expected to enter service with the US Army since 2024.

The crew of the new M1299 will consists of four (4) people including the commander, the driver, the gunner, and the loader.

With a new 155 mm L/58 calibre XM907 gun, longer than the M109s gun, M1299 will have and increased range and accuracy, and will also use the XM1113 rocket-assisted artillery shell.

Like the older M109, the M1299 self-propelled howitzer will have a traverse of 360°.

The standard rate of fire will be three (3) rounds per minute, buth with the autoloader the M1299 tracked SpH will be able to have a rete of fire of ten (10) rounds per minute.

M1299 will have a bigger effective fire range compared to the M109 howitzer, ranging between 70 and 100 km (43 to 62 miles).

The new M1299 155 mm self-propelled howitzer will be powered by a 600 hp Cummins diesel engine.