I was asked to look at a S&W 18-3 with a misfire problem and so far have come up empty.
The gun is in excellent condition, showing little use. When shooting double action, it will typically misfire 2 or 3 out of six chambers with .22 LR standard and HV ammo. Interestingly, all 6 chambers typically fire with the longer, CCI Stinger hyper-v ammo. All chambers typically fire single action, regardless of ammo.
Misfired cases show a noticable indentation, and may fire on a second hit if the DA trigger is worked very quickly. Staging the DA trigger slowly is almost certain to get misfires in most chambers.
A visual inspection turned up nothing. The gun was given a thorough cleaning, including the chambers. After cleaning, the chambers were lubed but then wiped as dry as possible.
The mainspring was replaced with a like-new factory S&W spring taken from a .357 mag K-frame. I am assuming the spring weight is the same on all K-frames, and that .22 revolvers don't come from the factory with a heavier spring.
After the above actions, the problem still persists.
Before I ship this out to S&W for service, I'd appreciate any advice.
The gun is in excellent condition, showing little use. When shooting double action, it will typically misfire 2 or 3 out of six chambers with .22 LR standard and HV ammo. Interestingly, all 6 chambers typically fire with the longer, CCI Stinger hyper-v ammo. All chambers typically fire single action, regardless of ammo.
Misfired cases show a noticable indentation, and may fire on a second hit if the DA trigger is worked very quickly. Staging the DA trigger slowly is almost certain to get misfires in most chambers.
A visual inspection turned up nothing. The gun was given a thorough cleaning, including the chambers. After cleaning, the chambers were lubed but then wiped as dry as possible.
The mainspring was replaced with a like-new factory S&W spring taken from a .357 mag K-frame. I am assuming the spring weight is the same on all K-frames, and that .22 revolvers don't come from the factory with a heavier spring.
After the above actions, the problem still persists.
Before I ship this out to S&W for service, I'd appreciate any advice.