I had this pistol as a teenager. It was then and still is to this day, the best steel BB pistol every made as I have realized over the years after wasting much money on trying to buy a replacement. Now it seems BB pistols are now mostly horrible plastic toys. I shot countless 1000s of BB through it without one problem. It had many outstanding features, especially compared to the pale out-sourced plastic toys that Daisy now imports. While there was no variations per se of this model, several later models utilized the same internal valve-barrel assembly namely the mod. 200, whereas the mods. 1200-1270 and 1500 made a change to a cocking mechanism, which made them no longer semi-auto. It was modeled after the Colt Woodsman 22 rimfire of which I had and bought the Daisy for backyard plinking. The grip is angled identically to the German Lugar which to this day allows the most natural pointing grip in the world.
The gun featured a magazine holding 8-9 BBs (I forgot exact numbers) by pushing a springloaded plunger allowing the BBs to feed from a 200 shot reservoir that was loaded through a movable cover on the back of the pistol under the rear sight. The gun was semi-auto firing the magazine as fast as you could pull the trigger before you needed to "recharge" it from the reservoir, by simply pushing the button forward just above the trigger and giving the gun a little shake; another excellent feature of this setup was that firing the last BB from the magazine would lock the trigger so you knew your needed to reload, no wasted "blank shots" with this gun. The rear sight was adjustable! and had the blade part protected much like a quality rear sight on a firearm! The trigger was outstanding for any BB gun, about 2-2.5 lbs, with very acceptable creep and over travel. It was all metal construction, plastic grips. The sight picture was excellent with the deep slanted front sight the sights were always well contrasted even in bright sun light. Due to the trigger and sights this BB gun was the most accurate BB pistol I have ever shot. I am not certain of the muzzle velocity but it appeared moderate, I doubt if it was doing greater that 350 fps. I too fell victim to Daisy non-repair just substitute policy... I sent mine if for repair and got the mod. 200 back instead, while it was the same functionally it no longer looked like my Woodsman and I felt it was down right ugly by comparison! I remember a desperate phone call to Daisy asking them to return my original Mod. 100 ( I knew that all I had to do was replace the internal barrel/valve assembly from the 200, but they told me that the gun was discarded. They learned a few new words that day. I have never bought another Daisy product in the last 45 years because of it.

I agree the mod. 100 was a nice pistol, its design was take from the Hyde pistol,there's quite a bit of history regarding this pistol.
Ejwills.
http://www.network54.com/Forum/405945/message/1152638514/The+Hyde+Automatic+CO2+BB+Pistol

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