In Pennsylvania, buying an AR-15 semi-automatic weapon is about as easy as buying lunch, experts say.

Go to a licensed gun store, sign the papers, complete an instant background check, pop down the money and walk out with the weapon.

No waiting period is necessary.

"You can buy an AR-15 as quickly as you can buy a cheesesteak," said Michael J. Chitwood, Upper Darby police superintendent.

"It is astonishingly easy," said Bryan Miller, spokesman for the Philadelphia chapter of Heeding God's Call, a faith-based movement to prevent gun violence.

For private sales, a background check is still needed to buy handguns, but not to purchase long guns, which includes assault rifles, said Miller.

Pennsylvanians, with the exception of those in Philadelphia, may carry weapons in the open, said Miller.

To carry the weapon under a jacket or in a pocket or transport a loaded gun in a car, owners must complete a separate application at a county level for a "license to carry," which can take up to 45 days, according to the state police website.

"Pennsylvania is the NRA dream state," said Miller.

New Jersey has a very strong assault weapons ban. The state's biggest problem with guns is the influx of weapons from Pennsylvania, he said.

The AR-15 that was used in Sunday's mass shooting in Florida is becoming "America's weapon of choice," said Chitwood.

It is lightweight, easy to clean, fast to reload, accurate for distance shooting, and extremely powerful.

It was used by gunmen in a classroom in Newtown, Conn., a movie theater in Aurora, Colo., and at a holiday party in San Bernardino, Calif.

"It is a devastating weapon in the wrong hands," said Chitwood.

By the numbers for 2014:

- 893,054 background checks were handled by the Pennsylvania Instant Check System

- 95 people with active warrants were identified by the PICS while attempting to buy a firearm

- 571,870 checks were automatically approved

- 328,252 were referred for more assistance

- 13,178 denials were issued

- 4,345 denials were challenged

- 2,543 final denials were issued

- 1,439 denials were reversed

- 354,603 handguns were reported purchased or transferred

- 321,496 long guns were reported purchased or transferred

- 219,782 licenses to carry firearms were issued by county sheriffs' offices and chiefs of police in first-class cities