In 2356, at the age of just thirteen, Kira Nerys knew how to operate a Bajoran phaser rifle and became involved in an ambush of Cardassian soldiers. She later recalled that during the mission, she continued firing until the power cell was completely discharged. (DS9: "The Darkness and the Light")
Later that year, Major Kira equipped herself with a Bajoran phaser rifle during a mission to locate the crashed Cardassian freighter Ravinok, that was carrying Bajoran prisoners. (DS9: "Indiscretion")
In 2374, as part of the Federation Alliance mission to retake Deep Space 9 from Dominion forces, Constable Odo assembled a security team comprising deputies with phaser rifles to combat Cardassian and Jem'Hadar troops on the station. During one engagement, his team rescued Major Kira and Rom after they had been pinned down by weapons fire, much to their welcome surprise. (DS9: "Sacrifice of Angels")
In 2377, the USS Voyager encountered an Hirogen outpost that had been modified using holographic technology given to them by Captain Kathryn Janeway three years prior. The outpost served as a "hunting ground" where Hirogen hunters could seek out holographic programs to satisfy their desire to kill. As the holographic technology given to them was of Federation origin, it was capable of simulating many Alpha Quadrant species. Iden, a Bajoran hologram, used the Bajoran phaser rifle during a fight against Hirogen hunters. (VOY: "Flesh and Blood")
In 2378, as a part of The Doctor's holo-novel Photons Be Free, Captain Jenkins had a Bajoran phaser rifle mounted on the wall behind her desk in the ready room of the fictional USS Vortex. (VOY: "Author, Author")
The Bajoran phaser rifle was designed by illustrator Jim Martin.   When designing the rifle, the prop department wanted to give it its own distinctive form so viewers could easily recognise it as Bajoran, a race who, at that point, were fairly new to the Star Trek universe. (Star Trek: Aliens & Artifacts, p.144)
The rifle itself was first seen on-screen in the episode "Shakaar" and featured prominently throughout Deep Space Nine's run.
In the script for "Ties of Blood and Water", the weapon is referred to as a "disruptor rifle" though it has always been referred to as a "phaser rifle" on-screen. 
The Bajoran phaser rifles were 25 inches long and made from solid cast resin with open shoulder stocks and straps. Many of the props were later resprayed and used for a variety of alien weaponry throughout Star Trek. Three of them were sold off in the It's A Wrap! sale and auction on eBay at a price of $2,400 (including premium). 
The weapon is featured in the Star Trek: Deep Space Nine Technical Manual, which states it uses a rechargeable isotolinium ampule as a power battery, although some units were retrofitted with sarium krellide energy cells in order to be used with Starfleet chargers. Furthermore, the technical manual reveals that early models of the weapon utilized a sensor which could differentiate between Cardassian and non-Cardassian lifesigns, though this fell into disuse after the Occupation of Bajor. It also mentions that the computer on Deep Space 9 regulated all rifles to setting 3 (heavy stun), in order to avoid fatalities and damage to the station's hull.
A variation of the Bajoran phaser rifle was used by security at Prison Complex 187 in the Deep Space Nine comic Turn of the Tide", set in 2368. In one scene, a Bajoran firing squad used them to shoot fleeing war criminals as they attempt to steal a Bajoran prison shuttle. The rifles themselves had extended upper barrels and are grey as opposed to the rust color as seen on-screen.