You can find a list of gun games and their features in the Mr. Pinball Price Guide. IMHO, the principal differences are in the type of gun (most are rifles, but there are pistols, machine guns, and space blasters) and whether you play based on time or number of shots. Interesting variations: free-handling gun (tethered instead of mounted), shooting physical projectiles, and 2-player games.
.................David Marston

The listings in the book will tell you which gun games had electronic sound boards or the embedded 8-track tape player.
.................David Marston