When Mikhail Kalashnikov designed the AK47 more than 60 years ago, I doubt he realized how this simple, extremely robust rifle would proliferate and be copied by so many countries. Even though the basic design has remained the same, subtle differences exist between specimens of different origin. There are many variants available today, and people often want to know which is best.

I'm curious about that too, so I recently compared three popular variants currently available through Century International Arms. They are all semiautomatic modernized AKM models characterized by stamped metal receivers instead of the older and more expensive milled AK receiver.

The Romanian GP WASR-10's receiver is manufactured in Romania, while the GP 1975 and Yugoslavian M70AB2 receivers are manufactured in the US. All three guns contain a mixture of new and used U.S. and foreign parts in order to comply with U.S. law.

The samples are all chambered in the original 7.62x39 Soviet round. All three operate the same way, and to the casual observer are the same, but there are differences--especially in their stocks.

The Romanian GP WASR-10 has rough, linseed oil-treated wood fore-ends and a matching buttstock. The stamped metal buttplate incorporates a trap door to stow a cleaning kit. The straight pistol grip is black polymer.

The GP 1975 stock is black polymer with the same profile as the GP WASR-10 but with a ridged stamped sheet metal buttplate that lacks the trap door.

The Yugoslavian M70AB2 has a buttstock that folds underneath the receiver, allowing the gun to be fired with the stock folded or extended. Its fore-end and pistol grip are black polymer.

Comparing features from front to back, all three have a slanted muzzle brake. Barrels are 16¼ inches long, but only the Yugo's is crowned and only the imported GP WASR-10 bore is chromed. Beneath each barrel resides a cleaning rod.

The GP 1975 and GP WASR-10 front sights are the same, but the M70AB2 has a heavier tower and is equipped with a deactivated folding night sight. The front sight posts on all three guns are adjustable for elevation.

All three rifles feature a gas block with a bayonet lug. However, the M70AB2 gas block is equipped with a grenade launcher sight that pivots upward and--when raised--obstructs the gas port.

All three tangent rear sights are adjustable for distance. All are graduated from 1 to 10 and have a battle-sight zero setting--marked "P" on the GP WASR-10, "0" on the others.

Behind the sight is the receiver cover. The GP 1975 and GP WASR-10 covers feature ridges for added stiffness; the M0AB2 cover is smooth. Thickness of the GP WASR-10 is .027 inch, the GP 1975 is .030 inch and the M70AB2 is .035 inch.

Outwardly, the stamped sheet-metal receivers look the same, but the GP WASR-10 has no dimples to reduce magazine side wobble, instead utilizing two pieces of metal attached to the inside.

While the Yugoslavian M70AB2 and GP 1975 receivers are made to accept 30-round magazines, the GP WASR-10 receiver--as imported--accepts only single-stack 10-round magazines until Century International widens the well.

The Romanian mag well measures 0.037 inch wider than the others and allows the bottom of a 30-round magazine to wobble about a quarter-inch from side to side--twice the play of the other two. Each gun comes with two 30-round steel magazines.

Attached to the right outside of the receiver is the safety, and all three are marked with an "S" and "F," but the M70AB2 lacks locking detents. Nevertheless, friction is sufficient to hold the safety lever in place. The M70AB2 lever has a small lower tab to clear the right arm of the folder while the upper tab is larger than the others and located to the rear. A scope mount is riveted to the left side of the GP WASR-10.