Field stripping the MK IV takes mere seconds, thanks to the rear take down button.

The elegant lines, modest price, and tack driving accuracy made it an instant hit with shooters and it became the most popular plinking and target rimfire pistol in the country. It stayed in production until 1981. In 1982, the Ruger MK II replaced it; offering the modest price and similar features but in a more diverse line of models to better suit the needs of competitive shooters. In 2005, it was replaced by the MK III series. The changes in the MK III were the addition of a magazine safety; moving the magazine release from the heel of the butt to the preferred American-style ‘behind the trigger guard’ position; and the top of the receiver was now drilled and tapped to allow the easy mounting of the increasingly-popular optical sights.

None of these model changes altered the accuracy and handling of the original Standard Pistol. They merely provided more options for shooters. Unfortunately, they also failed to address the biggest drawback to the original design—field stripping for cleaning.

To be ‘extremely charitable’, field stripping the MK I, II, and III series guns was not quite as simple as many would have liked. A shooting buddy of mine summed it up well when he said “You need a degree in mechanical engineering, and it doesn’t hurt to have a Voodoo Priest standing by to assist.”

I certainly concur. My experience with the MK I, and my current MK II, goes back over 30 years and I never truly mastered the take down. In fact, the last time my MK II was field stripped was a decade ago. That resulted in my arriving at my local gunsmith with the proverbial ‘paper bag full of parts’, a sheepish grin, and my wallet in hand.

That won’t happen with the new MK IV.

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