Because of restrictions on the sale of automatic weapons, civilians could buy the AR-15 only in a semiautomatic version.

The semiautomatic version of the AK-47 became popular with gun buffs in this country and it gained considerable notoriety for its ability to kill quickly and efficiently.

Some weapons, like the Uzi and the AK-47, are manufactured in both automatic and semiautomatic versions.

When the importing ban was imposed, for example, some domestic manufacturers of similar weapons, like the semiautomatic versions of the M-14 military rifle, stepped up production.

Also, because they are semiautomatic versions of military arms, a ready supply of ammunition and replacement parts is more assured.

The M-4 is a semiautomatic version of the weapon used by American Special Forces and paratroopers.

And because the gun was, by itself, a semiautomatic version of the Mac and not a machine gun, no Federal tax stamp, or license, was required.

Chinese manufacturers produce a semiautomatic version that was exported in huge quantities to the United States in the 1980's.

The anonymous author of a manual for converting the AR-15, the semiautomatic version of the military M-16, acknowledges that conversion violates the law.

But semiautomatic versions of such rifles, requiring a trigger pull for each shot, are available for sale over the counter in many cities.