Smith & Wesson is showing a new model 640 revolver at the 2010 SHOT Show. The very popular 640 is a five-shot, .357 Magnum “hammerless” revolver. S&W tweaked it for 2010, adding several new features that should prove to be popular.
First off, the old fixed sights have been replaced by a set of tritium, three-dot sights. Additionally, the sights are now dovetailed into the frame, meaning you can replace them without major gunsmithing if you so desire.  These sights are a huge improvement over the standard plain ramp and shallow notch found on the previous 640 revolvers.
Second, the barrel has been fluted, giving it a longer, leaner appearance. Â The fluting may also shave a few fractions of an ounce off of the total weight of the gun. Â For a concealed carry revolver, this is important for many people.
Lastly, and perhaps most importantly for many people, there is no internal lock in this model. Â The internal lock on the Smith & Wesson revolvers has been shown to cause the gun to “lock up” when shooting in certain, limited circumstances. Â Smith & Wesson hasn’t been very vocal about this problem in the past, and it would be nice if they came out and addressed this issue head-on with the shooting community.
I expect the lack of internal lock to sell more of this gun than the other features. However, I really like the fact the sights have been upgraded to tritium, and the fact that they are replaceable is a nice bonus.
Smith & Wesson 640 Specifications
- company SKU: Â 178044
- caliber: Â .357 Magnum
- capacity: Â five rounds
- barrel length: Â 2 1/8″
- sights: Â three-dot, tritium night sights
- grips: Â rubber
Update – October 2013
This version of the S&W 640 was introduced at the SHOT Show in January of 2010. Â As of October 2013, this gun is still in production and listed in the company’s catalog. Â The gun carries an MSRP of $809.