Just a quick question for anyone in the know: While using factory ammo/CCI in my Ruger Mk IV, I had 5 squib/low power discharges within 5 magazine loads. One even stayed in the barrel. My question is: Can a mechanical problem with the pistol, such as light strike, cause insufficient primer/powder burn in 22 LR. Note: After about 40 rounds and a good cleaning, everything has ran fine.

Any info would be appreciated.

I can’t answer the question definitively, but I do believe it’s within the realm of possibility.

I say that because long ago when revolvers were the kings of handguns, it was common to reduce mainspring power (especially in S&W models) to lighten the double action trigger pull weight. It was necessary to be careful to not lighten it too much and end up with light strike misfires, but it was easily possible to lighten the pull and still get reliable ignition. At one point, though, I ran across a study that looked into whether a lighter, but still reliable, firing pin strike could affect accuracy (or “precision” as it’s called today).

The study found that was what happened. As I recall, the study used the very accurate revolvers that fired light loads in common competitions of the day. It was found that lighter firing pin strikes resulted in velocity variations that were enough to degrade accuracy at the longer distances.

I don’t recall seeing anything further on the question ever since, but long range competitions with handguns that demand a high degree of accuracy have largely fallen out of favor, and with the handguns commonly used today it’s not possible to reduce the trigger pull weight by adjusting a screw as it is with S&W revolvers. Nevertheless, I believe the study demonstrated that firing pin impact force can affect how well the primers ignite the powder charge. One would think that it would be an all or nothing situation; i.e., either the charge goes off completely or it doesn’t go off at all, but maybe not.

Interested to read and learn more on this topic. Thanks OP for sharing what happened and the post cleaning results.

Thanks for the feedback and insight.

quote:

Originally posted by sigarmsp226:
Interested to read and learn more on this topic. Thanks OP for sharing what happened and the post cleaning results.

Your welcome. I ran another 40 rounds through it this morning and with zero malfunctions. So I am thinking the pistol just needed a good cleaning and some break in time.