The K38 I recently purchased fires great on single action, but when I attempt double action it does not fire. The firing pin does not even put a dent in the primer. I have never had a S&W revolver with this problem, the main spring screw all the way. Does any one have a clue what the problem could be?

The screw could have been shortened to lighten the pull or the spring could be weak. I've heard that you can put a fired primer cup over the tip of the screw to increase tension on the spring, but I've never tried it.

I move this to S&W-Smithing forum, where you should get more experienced replies.

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"I also cook."

It may have had the strain screw shortened. It could also have a different or altered main spring. Is the double action pull light? Lighter than other similar guns?
There's always the rare chance that some kitchen wizard altered the timing of the hammer drop in double action which would require replacement of the double action sear. If that was done I'd send it back to S&W.

Good luck & welcome to the forum.

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Lynnie, Professional Pest

It could be a S/A only gun.

Can you ascertain if the main spring screw has been filed down? Have you had the side-plate off for a thorough cleaning? It could be just a lot of old congealed oil & dirt. Does the action cycle through but just not enough force to set the primer off?

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H Richard
SWCA1967 SWHF244

I will take the screw our of the Model 19 and see if there is any difference in the length. I guess I could take the main spring out and switch them as well.

It is possible that either the strain screw has been shortened or the mainspring is weak.

Open the cylinder, hold the cylinder release to the rear, put the end of a finger over the firing pin bushing, and squeeze the trigger double action. If it doesn't sting, the spring isn't strong enough.

If you don't want the sting, you can put a penny over the bushing and try and dent Lincoln's head.

If you have another square butt K frame, you can pull the strain screws and compare the length.

All K, L, and N frame mainsprings are the same, if you want to swap in a different one to try.

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John 3:16
WAR EAGLE!

Well it looks like the main spring was the problem as I swapped out the one from the model 19 corrected the issue. The Screw as the same length as the one in the Model 19. The 60 year old spring needs replaced. Is the Wolff springs a good replacement or should I get an original S&W replacement?

Either should work well.

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Lynnie, Professional Pest

You could just hammer the original back flat & you'll be fixed up..
Alot of people tweak these springs trying to lighten the trigger pull..
Good Luck!!
Gary/Hk