The Colt Diamondback Revolver
By Chuck Hawks
Colt introduced the Diamondback double action revolver in 1966. The new gun was based on the Colt "D" frame, the same size frame used for the Police Positive Special and Detective Special models, but was a deluxe model with numerous special features. Like its Colt half-brothers, it was a 6-shot revolver with a swing out cylinder and a Positive Lock action that allowed safe carry with all 6 chambers loaded. Also like other Colt DA revolvers, the cylinder turns in a clockwise direction, into the frame, so lock-up is completely tight when the trigger is pulled back.
The Diamondback was introduced with a list price of $95 dollars, which was an expensive handgun in those days. The Smith & Wesson .38 Combat Masterpiece, the Diamondback's direct competition had a list price of $81 that year, and the Colt Government Model .45 Auto with a polished Colt Blue finish had a list price of $90. By 1986, the last year of production, the list price had risen to $461. The Diamondback's relatively high price limited its sales throughout its production life.
Diamondbacks are still available to shooters on the used market (the collectors haven't gotten them all, yet). According to the 23rd edition (Copyright 2002) of Fjestad's Blue Book of Gun Values, a shooter looking for a good used 4 inch or 6 inch Diamondback (95% condition) in .38 Special should expect to pay about $475. The same gun in mint (100%) condition will run about $650. Add 20% for .22 LR caliber, and 20% for nickel finish. The Diamondback is still an expensive revolver, but it is definitely worth the price. It is a better investment than any new revolver.
Calibers included .22 LR (also .22 Short and Long), .22 WMR, and .38 Special, but only a few .22 Magnum Diamondbacks were made. .22 LR and .38 Special were the common Diamondback calibers. .38 Special +P loads are safe for use in all Diamondback .38 Special revolvers.
Barrel lengths were initially 2.5 inches and 4 inches, and a 6 inch barrel option was soon added to the line. Diamondbacks with 2.5 inch barrels are least common (especially in .22 caliber), 4 inch barrels are the most common, and 6 inch barrels are most desired by shooters. The top of the barrel wears a ventilated rib, and there is a full length lug beneath, as per the Colt Python. The ventilated rib helps to dissipate barrel heat and reduce mirage effect, and allows a flat sighting plane. The full length underlug protects the ejector rod, minimizes bounce, and provides the weight forward balance preferred by target shooters.
The top strap of the Diamondback's frame is a flat top target type that is heavier than on the Police Positive Special and Detective Special models, strengthening the frame. The hammer has a wide, serrated, target spur and the trigger is a wide, grooved, target type. Diamondbacks came with a fully adjustable rear sight, usually mated with a ramp front sight. The grips provided on guns with 4 and 6 inch barrels are target type and made of checkered walnut with Colt medallions. Later on, black rubber Pachmayr grips with gold Colt medallions were made available as accessories to those who wanted them. Guns with 2.5 inch barrels came with checkered walnut service type grips.
The Diamondback is a target model service revolver and looks like the baby brother of the famous Python .357 Magnum. Its internal lockwork is of the same basic design, and uses the traditional Colt "V" shaped mainspring. Unlike the Python, the Diamondback did not come with a Custom Shop tuned action.
The all steel Diamondback came in bright nickel and polished Colt Blue finishes. The latter was the standard Colt blue, not the ultra-highly polished Royal Blue finish featured on the Python. The Diamondback remains, however, perhaps the finest .22 LR and .38 Special revolver of the modern era. Its grip is ideal for average size hands, easier for most shooters to control in double action shooting than the larger Python grip. Its action is generally superior to those of competing DA revolvers. The single action trigger pull is usually light and crisp and the double action trigger pull quite manageable.
The basic Diamondback numerical specifications are as follows. Weight: 25 ounces (.38 Spec., 2.5 inch barrel), 28.5 ounces (.38 Spec., 4 inch barrel); length: 9 inches (4 inch barrel). Caliber .22 Diamondbacks are about 3 ounces heavier than equivalent .38 Special models due to the smaller holes in the barrel and cylinder.
Due to its excellent sights, good trigger, fine balance, safe action, and moderate size a Diamondback makes a nearly ideal training revolver for a new shooter, male or female. Most persons unfamiliar with real guns are surprised by their weight. For this reason, beginners usually prefer the 4 inch barrel. Later they come to appreciate the advantages of the longer sighting radius and weight forward balance of the 6 inch barrel.
My favorite Diamondbacks have been blue guns with 6 inch barrels and Colt/Pachmayr target grips. I probably shoot my pair of 6 inch Diamondbacks (a .22 and a .38) more than any other handguns. The SA trigger pulls of both of these guns run about 3 pounds.
There is not much difference between the accuracy of a 4 inch barrel and a 6 inch barrel. There is, in fact, no difference in intrinsic accuracy, but the longer sight radius and greater weight of the 6 inch barrel gives it the edge in practical accuracy. And, of course, the longer barrel means superior ballistic performance.
My 6 inch .22 Diamondback will shoot 6-shot, 1.5 inch groups from a 25 yard bench rest all day, if the shooter is up to it. Sometimes that group size can be cut to 1 inch if I do my part particularly well.
This gun slightly prefers CCI Mini-Mag hollow point cartridges, but also shoots quite well with CCI Mini-Mag solid RN bullets. Unlike many .22 revolvers, it is not particular about ammunition, as long as it is the copper plated, high velocity, Long Rifle type. I have also had good results with Remington "Golden Bullet" and Winchester Super-X brands. This is my favorite plinking and small game hunting revolver, and it has proven a deadly squirrel gun with high velocity HP ammo.
My 4 inch nickel and 6 inch blue .38 Special Diamondbacks are usually fed inexpensive Winchester-USA "White Box" and Remington UMC ammunition with 130 grain FMJ bullets. Or my handloads with 140 grain Speer JHP bullets in front of enough W231 powder to give the same point of impact at 25 yards as the promotional factory loads. 25 yard 5-shot groups with these loads average about 2 inches from the 25 yard bench rest from either gun.
The latter is also an appropriate small game load. I like to think that it is somewhat more accurate than the economy factory loads, although it offer no particular advantage for small game hunting over the flatter shooting .22 LR high velocity HP cartridge.
My 6 inch .38 Diamondback gets the most use plinking at casual targets such as tin cans and clay pigeons propped against a dirt hillside. The 4 inch nickel Diamondback is my home defense gun of choice and is usually loaded with Glaser Blue Safety Slugs, as I live in a manufactured home. Its smaller grip gives me better control in DA shooting than my 4 inch Python.
I find the 2.5 inch .38 Special Diamondback too heavy for normal concealed carry, although after the whistle blows its heavy barrel, excellent sights, decent grip, and smooth action make it perhaps the most effective .38 snubby ever built. On the rare occasions that I have carried a concealed Diamondback, I have loaded it with Federal 125 grain Nyclad factory cartridges.
I am, unabashedly, a fan of the Diamondback revolver. I hope that at some point Colt sees their way clear to reintroducing this premium revolver to their line.
Copyright 2003, 2009 by Chuck Hawks. All rights reserved.