Smith & Wesson M&P340 J-Frame 1.875 in .357 Mag 5-Rd No Internal Lock
Video review
Expert review
About this product
What is the Smith & Wesson M&P340 J-Frame? It is a five-shot, lightweight scandium alloy J-frame revolver chambered in .357 Magnum and designed for concealed carry with a 1.875-inch barrel and a hammerless, snag-free profile. This model skips Smith & Wesson's internal lock safety mechanism, which is a common preference among shooters who prioritize maximum reliability and a cleaner internal mechanism. With its XS tritium front sight and double-action-only trigger, it's built for discreet, all-hours defensive use.
What is the M&P340 used for?
The M&P340 is used primarily for personal defense and concealed carry. Its 1.875-inch barrel and 13.3-ounce unloaded weight make it suitable for deep concealment in a pocket or on-body holster. The double-action-only trigger and shrouded hammer prevent snagging during a fast draw, and the .357 Magnum chambering provides significant terminal performance in a package smaller than most micro-compact pistols.
How does the M&P340 compare to a Ruger LCR?
The M&P340 trades the Ruger LCR's polymer frame for a scandium alloy frame, resulting in a heavier trigger pull but a more durable and precise-feeling action. Weighing 13.3 ounces versus the polymer LCR's 13.5 ounces, the M&P feels more substantial against recoil with full-power .357 Magnum loads, but its trigger requires consistent practice to master. The Ruger LCR is generally better for shooters prioritizing comfort, while the Smith & Wesson is better for those prioritizing material longevity and sight capability.
What does it weigh and what are the dimensions?
The M&P340 weighs 13.3 ounces (approximately 377 grams) unloaded, which is just under the weight of most modern smartphones. Its overall length is 6.31 inches, with a cylinder width of 1.31 inches and a height of 4.78 inches. This compact package easily fits in a standard-sized pocket holster measuring roughly 7 inches by 5 inches.
Who is this NOT for?
This revolver is not for first-time shooters or anyone primarily interested in range plinking. The 1.875-inch barrel and lightweight frame make shooting full-power .357 Magnum loads punishing; recoil is sharp and takes dedicated practice to manage effectively. It is also a poor choice for those who prefer a manual safety or the simplicity of a semi-automatic like our the Stevens 334 Rifle for a more straightforward shooting experience.
What's in the box?
The box contains the revolver, one five-round cylinder, a factory speedloader designed for J-frames, and an owner's manual. Unlike some competitors, Smith & Wesson does not include a soft case or extra grip panels with this model. Expect the total package weight to be about 21 ounces when shipped, including all factory paperwork.
Is the M&P340 worth it at $967.99?
At $967.99, the M&P340 is worth it for the shooter who demands a no-compromise, hammerless .357 Magnum carry revolver with premium materials. The scandium alloy frame and XS tritium sight justify its price premium over a standard Charter Arms revolver or Taurus polymer counterpart. For a similar price, you could purchase a more versatile compact semi-automatic pistol, but few offer this combination of material durability and concealment. For hunters seeking a different kind of dedicated tool, our Stevens 555 Sporting O/U Shotgun represents a more specialized long-arm investment.
Specs at a glance
Pros & cons
What works
- Weighs 13.3 oz unloaded — comparable to polymer frames but with alloy durability
- 1.875-in barrel keeps overall length to 6.31 in for deep concealment
- XS Sights 24/7 tritium front sight provides 10-12 year glow life in low light
Trade-offs
- No internal lock mechanism — a pro for some, but eliminates one safety option for storage
- Double-action-only trigger pull averages 12-14 lbs, requires significant training to master
- Sharp felt recoil with .357 Magnum loads — not ideal for extended range sessions
Key attributes
| upc | 022188030723 |
| manufacturer | Smith & Wesson / S&W |
| manufacturer part number | 103072 |
| action | Double Action Only |
| atf type | Revolver |
| barrel finish | MATTE BLACK |
| barrel length | 1.88" |
| caliber/gauge | .38 Special |
| capacity | 5 |
| color | Black |
| length | 10 |
| magazine included | Cylinder |
| model | 340 |
| package height | 2.4 |
| package width | 7.0 |
| product type | Revolver |
| safety | No Internal Lock |
| shipping weight | 1.5 |
| sights | XS Sights 24/7 Night Front, Integral U-Notch Rear |
| sights type | Night Sights |
| state restriction (guam) | NO SALE TO GUAM |
| state restriction (pr) | NO SALE TO PUERTO RICO |
| state restriction (vi) | NO SALE TO VIRGIN ISLANDS |
| units per box | 1 |
Frequently asked questions
- Is it compatible with standard J-frame holsters?
- Yes, the M&P340 is compatible with any standard J-frame holster cut for a 1.875-inch barrel and a shrouded hammer. Due to its XS tritium sight, some kydex holsters made for older models may require slight modification near the front sight channel. I recommend a molded holster from DeSantis or a custom maker for the best fit.
- Does this work with speedloaders?
- Yes, it works with standard five-round J-frame speedloaders from Safariland (Model Comp II) and HKS (Model 36A). The cylinder release is positioned for right-handed operation, and reloads typically take 3-5 seconds with practice. Avoid using .38 Special wadcutter rounds in speedloaders, as they can sometimes hang up on the shorter cylinder.
- How long does shipping take?
- For in-stock items, standard shipping through our partner Ironclad Armory takes 3-5 business days to the lower 48 states after FFL verification is complete. Expedited 2-day air service is available for an additional $35. All firearms ship within 1 business day of receiving a valid FFL copy from your chosen dealer.
- Can I return it if it doesn't fit?
- Returns are accepted only for unopened, unmodified firearms within 14 days of delivery, subject to a 15% restocking fee and return shipping costs. Once a firearm has been transferred through an FFL, it cannot be returned for fit or preference reasons. We recommend verifying grip dimensions at a local dealer if you are unsure about the ergonomics.