Ever since the 1997 North Hollywood bank robbery and shootout, the popularity of rifles in patrol operations has exploded. Today, there are very few police agencies in the United States that don't issue rifles to some patrol officers or allow their officers to purchase rifles for use on patrol.

Rifle manufacturers have capitalized on this demand, and they are now making a variety of rifles specifically designed for patrol and SWAT operations. Here's a quick look at some of the long guns now available for service in law enforcement.

Bushmaster Gas Piston Rifle

The Bushmaster Gas Piston Rifle was created to give shooters a cleaner and easier to maintain version of the Bushmaster M4. The company says that the internal area of the upper receiver, including the bolt, bolt face, extractor, and firing pin, are kept cleaner and cooler than in conventional M4/AR-15 rifles because a sizable percentage of the hot gas and debris that would normally be injected into the upper receiver is kept inside the gas piston chamber to power the operating rod. The gases and burned powder that are not used to power the rod are vented from the rifle.

Daniel Defense M4 Carbine

Best known for making accessories for AR-15/M16 platform rifles, Daniel Defense is now making its own "black gun." The Daniel Defense M4 (DDM4) is manufactured using the same 3D engineering technology as the company's popular free float rail systems.

This carbine is loaded for bear with features and custom touches. It has a Daniel Defense Omega X rail, a Magpul five-position MOE receiver extension buttstock, and a 16-inch chrome-lined barrel.

DoubleStar Star 15 Patrol Rifle

When the first Star 15 patrol rifle was released some three years ago, DoubleStar president Teresa Starnes told the press: "The design was derived from extensive interviews with front line police officers. The consensus reached was a lightweight package readily adaptable to almost every situation." The Star 15 Patrol Rifle is built on an A-1 configuration with a one-in-nine twist barrel.

Capable of MOA accuracy, the Star 15 Patrol Rifle has a phantom flash hider, a YHM four-rail hand guard, a GG&G flip-up MAD rear sight, a Hogue rubber pistol grip, and a DSC six-position M4 buttstock. Available upgrades include a chrome-lined barrel, a two-stage trigger, an H buffer, and a bipod. The Star 15 is available in a variety of configurations, including a CAR-15 carbine and a match rifle with a 20-inch barrel.

DPMS Panther Arms AP4 Panther Carbine

The AP4 Panther Carbine from DPMS Panther Arms is an excellent basic patrol rifle built on an M4 platform. With a 16-inch chrome-moly-lined contour barrel, the AP4 is suitable for both close-quarter combat and counter-sniper applications.

Other features include GlacierGuards hand guards, a flat top receiver with Picatinny rail, and a telescoping fiber-reinforced six-position buttstock.

FNH USA SCAR Light

Designed for U.S. SOCOM operations, FN's SCAR is a next-generation military rifle available in 5.56mm and 7.62mm NATO, SCAR Heavy and SCAR Light. The SCAR is a short stroke gas piston rifle that is magazine fed, air cooled, and is available in select fire and semi-auto versions. It's also lightweight but has very little recoil thanks to its excellent ergonomics. The SCAR was built for flexibility.

Each model can be fitted with three different barrels to achieve different mission goals. The 10-inch barrel and folding stock make the SCAR into a close quarters subgun; the 14-inch and 18-inch barrels are more suited to longer range applications. The side-folding polymer stock is fully adjustable for comb height and length of pull.

Kel-Tec RFB 

Kel-Tec's RFB rifle is a bullpup design. In fact, RFB stands for "rifle forward ejection bullpup." Chambered for 7.62mm cartridges, the RFB has a Picatinny rail and fully ambidextrous controls.

The trigger has up to five individual adjustments, and the safety disconnects the trigger and blocks the hammer action. RFB rifles use FAL magazines.

Remington 7615 Patrol Rifle

Designed for law enforcement agencies that want patrol rifles but don't want to use so-called "assault weapons," the Remington 7615 is a unique patrol rifle. Unlike other patrol rifles it's not semi-automatic; it's a pump-action rifle that works pretty much like a Remington 870 shotgun. In fact, the 7615 is kind of like a hybrid of a Model 870 shotgun and an AR-15.

This pump-action rifle fires .223 Remington cartridges, and it uses a 10-round low-profile AR-15 magazines. The rifle is available with ghost ring or standard rifle sights.

Rock River Arms Elite Comp LAR-15 Rifle

Chambered in .223 Remington and 5.56mm, the Rock River Arms Elite Comp LAR-15 rifle offers many of the features of a custom rifle. The forged flat top receiver has a front and rear flip-up that can be used with or instead of optics. For mounting accessories, it has a Rock River Arms half quad free-float, mid-length handguard.

Other features include a Magpul CTR stock and an Ergo SureGrip. The Elite Comp LAR-15 has a two-stage trigger with a winter trigger guard that accommodates operators wearing gloves.

SIG Sauer SIG556 SWAT

The latest incarnation of the SIG556 is a carbine designed specifically for SWAT operations, the SIG556 SWAT. Like all SIG556 rifles, the SIG556 SWAT uses a full-length gas piston with rotating bolt. It features an aluminum quad-rail hand guard for mounting lasers, lights, and other accessories.

Designed for close-quarter battle, the SIG556 SWAT has a Swiss-style hinged folding stock. The stock interface is built directly into the trigger casing, and the stock snaps and securely locks into position with a length of pull that can be preset by the user. Although it was clearly designed for use with CQB optics such as Aimpoint, EoTech, and Trijicon, the SIG556 SWAT has rear rotary diopter sights that can be calibrated from close-quarter ranges out to 300 meters.

Springfield Armory SOCOM 16 Rifle

A few years back the U.S. spec ops community approached Springfield Armory and asked the company to update the venerable M14 for contemporary close-quarter battle in Iraq and Afghanistan. What the spec ops guys needed was a short barrel carbine with a lot of punch, and the SOCOM II rifle was born.

The SOCOM II is essentially a 21st century version of the M14. This 7.62mm rifle has a cluster rail system, its stock is glass fiber instead of wood, and it has a high-efficiency muzzle brake designed to reduce muzzle flip and keep the rifle on target.