Quick look at why I prefer the Ruger Mk II over the Mk III handgun.

I've been able to shoot a Ruger Mk I, Mk II and Mk III on and off for the past few years, It wasn't until I laid my hands on a Mk II that I realized how much more I preferred the Mk II over the I and III. Usually the most current versions of firearms are somehow improved upon on, I feel like this is not the case in recent years especially with the Ruger Automatic series of handguns.

The implementation of various safety features detract much of the ruggedness and value of the firearm, even if the devices have little or no effect on function. The Mk III was downgraded it seems when you start to look at exactly what was changed. Really quick the big difference between the I and II is the last shot bolt hold open lacking on the Mk I.

There are 5 main differences between the Mk II and Mk III, differences that I feel make a major impact in the guns value and usability. The following is what I recognize as the shortcomings of the Mk III over the previously produced Mk II.

-Loaded chamber indicator
-Lock out
-Magazine release (Button vs. European)
-Charging tab width
-Magazine safety (found on the MK III)

Here we see the Mk III, 3 things to see here #1 the magazine release right behind the trigger. #2 The loaded chamber indicator located on the receiver (long strip) and the lock out located just below the safety.

Here we see just how much "cleaner" the side of the Mk II is 

Mk III Tabs are narrower, could be a boon if you are worried about snagging.

Mk II tabs are noticeably wider allowing better grip to charge the firearm. 

Mk II on left - Mk III on right , tabs are just a little wider than the receiver. As an aside notice how much taller the adjustable sights are on the Mk III, I have a thing for sights that are low on the gun, they always seem more natural to shoot.

here we see the Mk III stock gun/magazine is most of the time not drop free.

Mk II magazine release, the author finds this easier to use with gloves than the Mk III.

The mark II magazine release is that of a European style. I much prefer this over the Mk III style stock release because if you'll notice your mags don't always drop free (stock gun mind you). Your hand goes down to the bottom of the grip to remove the magazine in both cases. With the Mk II gun your weak hand goes to the base of the grip to release the magazine as well remove it. The Mk II is also easier to load and unload while wearing gloves from my experience. 

The Mk II is lacking the mandated safety devices Ruger has applied to their Mk III models, a lock and loaded chamber indicator now adorn the Mk III making them marvelous dirt traps and extra parts to clean. I have not personally had any problems with my Mk III and the two installed safety devices, but I have "heard" of some people that have had problems with the loaded chamber indicator. These isolated cases should not be considered a major or even a minor problem (I would be interested in hearing specific issues with these features however if you have had them). The Mk III I own has performed exceedingly well for me.

I will admit this evaluation was done under the thought of a functional woods carry gun and not a range only gun. I will also add the fixed sights on the Mk II are very accurate for fixed sights, the front blade is  narrower than that on the adjustable sights which mean aim small miss small when your plinking game.

If you are considering a Ruger .22 Automatic handgun see if you can get your hands on a Mk II and a Mk III to compare side by side. I feel like the Mk II has much more to offer over the Mk III if you are looking for woods/pack gun.