Pedersoli Cook Underhammer, a simple and accurate sporting gun – and suitable for left-handed people as well

The trigger assembly is simple but highly effective, with the hammer spring also acting as the trigger guard. 

Muzzle-loading pistols with the hammer below the barrel, or underhammers, were among the first to use copper percussion caps, which were invented around 1820. In this type of gun, the nipple and hammer are located below the barrel; therefore, when firing, sparks and any splinter from the cap are prevented from striking the shooter's face. In addition, the hammer does not interfere with the line of sight. This is a type of pistol that is improperly referred to as a "saloon gun" whereas in fact was very popular for defensive use, especially in America in the first half of the 19th century. The peculiar hammer position, in fact, made carrying and drawing easier. We envisage a more peaceful use for this pistol with its essential but not charmless lines, dominated by the saw-handle grip and the two-order barrel: it starts with an octagonal profile at the breech and then becomes circular two-thirds of the way down.

Video: Pedersoli Cook Underhammer muzzle loading pistol in .36 caliber

Pedersoli Cook Underhammer muzzle loading percussion pistol

The pin that secures the barrel to the grip is easy to remove and makes it very easy to maintain the Cook Underhammer.

The Pedersoli Cook Underhammer is a .36 caliber muzzleloading pistol with rifled barrel and a percussion lock. It is an ergonomic and easy-to-maintain firearm, thanks to the barrel locking system consisting in a conical pin that locks together the barrel assembly and frame. The lock is very simple, at least in appearance, with a small hammer operated by a leaf spring that also forms the trigger guard. It is an elegant and very functional solution, enhanced by the adjustable trigger travel.

The Cook Underhammer's rear sight is easily adjustable and replaceable. Also note the functional grip spur.

The front sight is dovetail-mounted on the barrel and is easily windage-adjustable, while the rear sight is screwed onto the tang and can be easily adjusted in elevation or replaced. The grip is walnut, and in its simplicity is one of the secrets of the Cook Underhammer. The saw handle allows a very firm and natural grip, and the large checkered areas allow excellent control when firing. In addition, the completely symmetrical design and central hammer position make this gun fully ambidextrous, much to the delight of left-handed shooters. Aesthetically, the oil-polished wood makes the Underhammer very pleasing to the eye, which never hurts.

The PMG (Pedersoli Match Grade) barrel measures 205 millimeters (8 1/16") and is broach-rifled with seven grooves and a 450-mm twist. Since it is an absolutely identical replica of an original, the Cook Underhammer can be used in shooting competitions of the MLAIC circuit. Until now, Pedersoli's Cook could compete in the Kuchenreuter division, but it is news these days that from the next edition of the muzzle-loading championship there will be a specific category for underhammer guns.

The front sight is dovetail-mounted on the barrel and is easily windage-adjustable.
The oval-shaped grip is definitely one of the most successful details of the Cook Underhammer.

Our shooting impressions with the Cook Underhammer

The Pedersoli Underhammer is fitted with an excellent adjustable trigger, featuring a very crisp break. One must be used to sporting guns of a certain level, as such a light trigger is not suitable for "green" shooters – but it is possible to adjust it according to one's experience and ability. The feeling is like pulling the trigger of a good free pistol, or a bench rest rifle. For shooting with such light pull weights, a secure and ergonomic grip on the handle is absolutely essential. In this, the Underhammer surprises, despite its seemingly archaic and simple "pear" shape: with its finely checkered walnut upper handle spur, the grip is very secure and allows excellent mobility and independence of the index finger to operate the trigger. Release is perfectly smooth, with virtually no perceptible overtravel and a very short travel, all of which allow for the gun's accuracy to be expressed at its best. The Underhammer behaves nicely when fired, with a perceptible but extremely controllable delay before discharging, and exceptional stability. As a semi-automatic pistol shooter, an enthusiast of dynamic and informal shooting, I am very surprised to see the level of accuracy that a simple round ball wrapped in a patch achieves in a in a rifled barrel.

Thanks to the central hammer position and the perfectly symmetrical grip design the Pedersoli Cook Underhammer is fully ambidextrous.

The necessity of having to reload each shot, brushing the barrel from time to time to remove the bulk of black powder residues, pouring the powder and inserting the ball wrapped in the greased rag from the muzzle, then literally hammering it down on the charge at the bottom of the barrel, allows for great reflection when firing, with almost Zen-like concentration.

Wrapping up

The Pedersoli Cook Underhammer carries a retail price of 1,042 euros. Certainly this is a good choice for those who are approaching sport shooting with muzzle-loading guns and want to skip over cheap firearms that will soon begin to show their limitations. The Cook Underhammer is easy to use, very accurate, has a superb trigger and is perfectly ambidextrous, so it is also attractive to left-handers. The possibility of using it in MLAIC competitions in a dedicated category makes it further attractive to the sport shooter. 

Pedersoli Cook Underhammer specs and price

Cook Underhammer
Percussion gun
Single stage, adjustable
Adjustable front and rear
Barrel Length:
205 mm
920 g 
1,042 euro

For more information on the Cook Underhammer gun please visit the Pedersoli website.

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