Direct proof of use
Small Arms Survey identifies 107 mm rockets used by armed groups in Afghanistan and Iraq as mainly Chinese-designed Type 63-series rockets and foreign variants. It describes those rockets as common insurgent artillery rockets, used for indirect fire and also adapted into improvised explosive devices and improvised rocket-assisted munitions.
Reporting on June 2008 attacks in Baghdad described IRAMs fired by Shiite extremist groups as using rocket casings of the type associated with the Chinese-made Type 63 107 mm rocket system. The same reporting attributed several attacks to the improvised rocket-assisted munition pattern that had appeared in Baghdad that spring.
Sources: Rogue Rocketeers, WIRED Flying IED
Timeline
By 2007 and 2008, U.S. and Iraqi reporting cited frequent insurgent use and recovery of 107 mm rockets and improvised launch rails in Iraq. Small Arms Survey's review of official reports found that armed groups had acquired and used hundreds of 107 mm rockets in Iraq and Afghanistan, with most 107 mm and 122 mm rockets employed as indirect-fire weapons from factory-built or improvised launchers.
In April 2008, rockets struck eastern and central Baghdad during fighting around Sadr City, including three 107 mm rockets in one sequence of attacks. In June 2008, WIRED reported on IRAM attacks in Baghdad and connected the rocket casings used in those weapons to the Type 63 107 mm rocket system.
Sources: Rogue Rocketeers, WIRED Flying IED
Narrative
In Iraq, the Type 63-series rocket filled an insurgent indirect-fire role rather than a conventional artillery-battery role. Armed groups fired 107 mm rockets from improvised rails, tubes, and other simple launch frames against bases, urban districts, and other area targets. Small Arms Survey notes that improvised launchers reduced accuracy but made the rockets easier to conceal and transport, which suited attacks on large fixed targets.
The same rocket family also appeared inside IRAMs, often called flying IEDs, in which the warhead of a conventional artillery rocket was replaced by a larger explosive canister. Small Arms Survey states that some IRAMs recovered in Iraq were constructed from Iranian-origin 107 mm rockets and that IRAM use in Iraq was reportedly concentrated among a small number of Iranian-backed Shia groups, with Kata'ib Hizballah responsible for most such attacks.
Sources: Rogue Rocketeers, WIRED Flying IED