Review: Diamondback 357 Magnum 6-Shot Snub-Nosed Self-Defense Revolver
Florida's Diamondback Firearms has been marketing a little-known snub-nosed six-shot .357 for the past year. We have a review covering both the good and the bad on the new SDR.
Diamondback is best known for its compact 9mm semi-auto pistols, AR line, and interesting 5.7mm DBX platform. However, the company has been creeping into the world of wheel guns for a few years, starting with the double-action (that looks like a single-action) nine-shot Sidekick rimfire revolvers that debuted in 2021.
Breaking new ground as a company, Diamondback moved into the centerfire revolver market at SHOT '24 when it debuted the Self Defense Revolver, or SDR, in a bright stainless finish, soon followed up by models in a more subdued glass bead satin stainless and a tough-wearing black nitride. A six-shot .357 Magnum, it is a snub-nosed compact revolver with a 2-inch barrel.
The overall length of the Diamondback SDR is 6.53 inches, while its height is 4.44 inches. Weight is 21.2 ounces. Note the short underbarrel lug. (All photos: Chris Eger/Guns.com)
Comparing the SDR to other snubs on the market, it is about the same dimension as Smith & Wesson's J-frame .38 Special five-shooters, albeit a bit heavier, which is not a terrible thing for a pocket-sized .357 Magnum. Of note, the Kimber K6s, another six-shot .357 snub, is a couple of ounces heavier than the SDR.
The overall styling and push-button cylinder release evoke the Kimber K6 series and help keep the width down to 1.38 inches over the semi-fluted cylinder itself.
The SDR is compared to an S&W 642. Note how dimensionally close in size these two are, varying in fractions of an inch here or there. Of note, the SDR is a six-shot .357, while the 642 is a five-shot .38.
For full disclosure, Diamondback provided this SDR to Guns.com for review purposes. All testing was done on this one gun, which has been under evaluation since June.
The Specs
Overall length: 6.53 inches
Barrel length: 2 inches
Overall width: 1.38 inches at the widest point over the cylinder
Overall height: 4.44 inches
Capacity: 6-shot cylinder
Sights: Fixed, green low profile fiber optic rear, orange fiber optic front
With a beefy frame constructed of forged stainless steel with a matching barrel and cylinder of the same material, the SDR fills the palm and hits the scales at just over 21 ounces, unloaded. A half dozen rounds of 145-grain Winchester Silvertip jacketed hollow points bring that up to just 24.4 ounces.
The high-vis sights are much better than those found on most snubbies, especially those priced under $1K. Running dovetailed low-profile rear sights complete with a two-dot green fiber optic, the front post is a fixed orange FO rod and really pops.
The sight radius is 3.6 inches across a flat top strap with fenced sides. The trigger spur sits low enough to keep a full sight picture during the firing process.
Note the trigger guard is tapered towards the front, which may give some sausage-fingered gents wearing thick gloves a bit of heartburn. I've got big mitts and didn't have an issue.
An interesting facet of the SDR is the fact that the cylinder and crane link assembly can be easily removed in one contained package, via a push-button release on the right side of the frame. The cylinder will only be released when in the open position, so you don't have to worry about the revolver disassembling itself in the holster.
All the edges are melted, leaving virtually no sharp points and few snag points other than the exposed hammer spur. Is Diamondback going to run a double-action-only SDR with a shrouded hammer? Who knows – but I wouldn't be surprised.
The fit and finish of the SDR is excellent and gives the revolver a refined feel. Note the barrel has a 45-degree target crown.
The cylinder has a "melted" look to it showing nice fluting, which helps save an ounce or two in carry weight and keeps the overall width down to 1.38 inches across its widest point. The SDR is chambered in .357/.38 and is rated for +P rounds. It is a "left wheeler" in the respect that the cylinder rotates counterclockwise (leftward), a trait shared by almost every double-action revolver maker except for Colt, Enfield and Webley.
The cylinder chambers are polished, which cuts down on having to wrestle stuck cases during a reload. It accepts common K-frame pattern speed loaders.
This allows for easy use with existing prep blocks and loaders, which can make range time a lot more enjoyable than loading one round at a time from a box.
The forcing cone isn't just a plain cut barrel chamber and has been chamfered. It has a uniform cylinder gap.
It ships with Diamondback-branded Hogue overmolded Monogrips, one of the most popular styles over the past couple of decades, especially when it comes to recoil mitigation. The grips are a standard J-frame pattern, meaning there are hundreds of aftermarket options already floating around.
The cylinder release is a push-button type like the one used on Kimber's K6 series. The manipulation, while a departure from the slide or pull style release seen on Colts and S&W revolvers over the years, is familiar to those who are used to dropping a magazine on a semi-auto.
Trigger
We found the SDR's double-action/single-action trigger smooth compared to other factory revolvers. Non-stacking, it broke clean at an average of 9.9 pounds in double action, dropping to 2.3 pounds in single action.
A video of the trigger at work on the range:
Reliability
The SDR right out of the box exhibited good lockup and timing. We fired a mix of over 500 rounds through it in three range sessions, and the cylinder kept time and exhibited no shaved lead or binding. The recoil was a bit stout with full-powered +P .38 loads and .357s but was still controllable, and the revolver was easy to get back on target for follow-up shots. The only problem we encountered was user-induced errors (short-stroking the trigger in DA mode). Also, after a few hundred rounds, we felt the need to run a bore rope through the barrel and cylinder to pull out the carbon buildup and reduce overall gumminess.
The ammo involved included 300 rounds of PMC Bronze 132-grain FMJ target rounds with an advertised velocity of 912 fps and another 100 of Federal's American Eagle 158-grain FMJs with a spicier 1,240 fps. Self-defense rounds were Federal's 120-grain Punch and 129-grain Hydra Shok .38SPL+P JHPs with a 1,000/950 fps velo, along with Winchester's 145-grain .357 Mag Silvertips, which pushed 1,290 fps.
While you could feel the difference between the low-recoil .38s and the more full-flavored .357s in terms of recoil, at no point was the SDR uncontrollable.
Accuracy
Small-framed snub-nosed revolvers are not renowned for their accuracy at distance, particularly when fired in double action. This is compounded by the narrow, round butt grips and fixed sights. However, the SDR proved more than capable of practical accuracy at 15 yards. Pushing back to 25, we were still able to hit an IPSC plate with some concentration, albeit with a lot more Charlies and Deltas than Alphas.
Rapid fire at the 15 unsupported.
Carry
Much like the SDR accepts widely available K-frame speed loaders, its doppelganger dimensions compared to the J frame means most holsters that fit the S&W snub-nosed line (or 2-inch K-frames and Security/Speed Sixes, et.al.) will likely work on Diamondback's .357. A little heavy for pocket carry at 1.5 pounds loaded, the SDR nonetheless fits our go-to pocket snub holster, the DeSantis Nemesis. It also fits the Bianchi No. 6 suede inside the waistband concealment holster and Galco's beautiful Combat Master professional-grade belt holster.
We found the SDR to fit many common holsters already on the market.
Pros & Cons
Pros
Excellent value when stacked against its competition
Accurate
Reliable
Compact
Has great sights
Uses common holsters, speed loaders, and grips
Has a quick-detach cylinder assembly
Cons
Diamondback's first centerfire revolver
Conclusion
Snub-nosed carry revolvers have arguably been around since 1849, when Colt hit the market with the "Wells Fargo" Pocket model. Now pushing into their 175th year, there is a reason they are still popular: a blend of simplicity, reliability, and concealability. A quick look shows Charter Arms, Colt, Kimber, Ruger, S&W, Taurus, and now Diamondback as making new DA .357 Magnum wheel guns for the carry market. Of those, the six-shot SDR, with an MSRP of between $777 and $853 depending on the model, typically falls less than a Kimber, Ruger, or Colt; about neck and neck with a five-shot S&W Model 60 with plainer sights, and a little more expensive than something like a Charter's five-shot .357 Mag Pug or the similarly five-shot Taurus 605.
We've been kicking an SDR around for several months and found it easily supportable, dependable in use and operation, and innovative with its removable cylinder assembly. Further, while not meant for long-range benchrest target shooting, it is accurate to fill the needs of your typical EDC snub gun.
Did Diamondback knock it out of the park their first time at bat when it came to a centerfire revolver? Looks like it.