There is no magazine safety; the pistol fires with magazine out. Each Cougar comes with two high-capacity magazines: the .40 S&W magazine holds 10 rounds and the 9mm magazine takes 15 rounds. Nominal empty weight for both versions is given as 32.6 ounces by the manufacturer.

(LEFT) The rotary takedown lever is located forward of the trigger guard. (CENTER) Mag release, slide-lock lever and safety/decocker are within fingertip distance for easy, convenient access. (RIGHT) All edges on the Cougar are rounded for snag-free drawing.

In terms of design, the most noteworthy aspect of the Cougar pistol is its rotary barrel locking mechanism, which is definitely outside the mainstream of semiauto pistol mechanics. The only other rotary-barrel pistols I know of (similar in concept but not specific design) include systems marketed around 1900 in the United States by Elbert Searle and by Roth in Austria, the short-lived Colt All-American 2000, the Russian P96/P96S/P96M pistols, the Slovakian K-100 Grand Power pistol and the Beretta PX4 Storm.

Virtually all other makes and models of conventional duty/service-type centerfire autoloaders employ some variation of the recoil-operated tilt-lock mechanism (either cam-block or swivel-link) originally developed by John Browning for the 1911 and Hi-Power pistols.

In contrast, when a Cougar fires, recoil energy pushes the locked-together slide-barrel assembly backward as a unit for about a quarter inch, while the bullet exits the muzzle. Then an angled slot in the breech area of the barrel encounters a tooth (in Beretta/Stoeger terminology) that protrudes upward from a separate steel part called the central block, which sits within the aluminum frame and encloses the full-length captive guide rod/recoil spring assembly.

ACCURACY RESULTS: Stoeger Model 8000 Cougar
LOAD	BULLET WEIGHT (gr.)	AVG. VELOCITY (fps)	EXTREME SPREAD (fps)	AVG> GROUP (in.)
.40 S&W
CCI Blazer HP	155	1,213	31	2.15
Federal Hydra Shok JHP	135	1,141	22	2.25
Remington Golden Saber	165	1,107	17	2.18
Speer Gold Dot	165	993	20	2.00
Winchester JHP	180	965	23	2.13
9mm
CCI/Blazer TMJ	115	1,047	28	2.13
Federal JHP	115	1,030	18	2.13
Hornady XTP HP	124	1,002	31	2.00
PMC Starfire	124	1,015	52	2.50
Remington Golden Sabre	124	1,015	52	2.38
Winchester SXT	147	900	50	2.25
Data are averages of five full-magazine groups fired from a benchrest at 25 yards. Velocity data are averages of 10 rounds measured 15 feet from the muzzle by an Oehler M35 Proof Channel Chronotach/Skyscreen III system. Abbreviations: HP, hollowpoint; JHP, jacketed hollowpoint; TMJ, truncated metal jacket

As the slide/barrel unit progress on backward, this tooth causes the barrel to rotate approximately 30 degrees, causing the barrel locking lugs on the opposite side to turn out of alignment with their slots in the slide.

The barrel then comes to a stop against the face of the central block, while the slide continues rearward, extracting and ejecting the fired case and compressing the recoil spring--which then completes the action cycle by returning the slide forward to feed the next cartridge from the magazine into the chamber and re-rotating the barrel back into lockup. The rotary barrel design requires a fully enclosing slide, so the "cutaway" exposed-barrel slide that is typical of all other Beretta centerfire pistols except for the CX4 Storm is not a Cougar feature.

As a design, a rotary barrel has several benefits in comparison to tilt-lock mechanisms. First, the lock/unlock time is very short and can be varied to accommodate the pressure curves of different cartridges simply by altering the angle and length of the camming groove in the barrel without major redesign or alteration of the overall frame. The "premature unlock" and "primer wipe" problems that have plagued many new-cartridge adaptations of existing tilt-lock pistol platforms (like early .40 S&W pistols built on 9mm platform designs) would never have occurred in a well-executed rotating-barrel system.