My Pre Lock L Frame has difficulty. Sometimes when pulling the trigger it lock ups. The trigger basically can't be pulled rearward. Then I release the tension, try again, and it's fine. It never locks up when pulling the hammer. What could be causing this?

C77

Depends where it locks. If it as the start of the trigger pull, it's probably the cylinder stop not releasing. If it is part way through, it might be a problem with the ratchets on the extractor star. Check to make sure the ejector rod is not working loose.

One thing to try is while pulling the trigger try pulling it to ones side or the other instead of straight back. Have you cleaned and oiled the internals?

The problem may be the trigger stop if your gun has one.
Look at the upper rear of the trigger to see if there is a small crescent shaped piece protruding from the trigger guard.
If so that is the trigger stop. It is adjustable by loosening the screw that holds it in place. This screw can loosen over time and allow the stop to move. You will be able to cock the hammer but the trigger stop will prevent you from releasing the sear and so locks the trigger. If that is what is happening take a small screwdriver and see if you can move the stop back towards the trigger guard. If that works you now have to get access to the inside of the frame and tighten the stop screw. If you have not done this then I would suggest you have a gunsmith do if for you as getting the side plate back on can be troublesome.
Zeke1

Does it happen more when you're shooting fast? I have noticed that if I don't let the trigger go all the way forward the same thing happens. It causes the cylinder stop to not release, as mentioned by bountyhunter above. The cure is training your finger to let the trigger go ALL the way forward. It's not like a Glock or a 1911 where you start squeezing again after the trigger clicks the first time. There are two clicks then a hair more.

Yep. That's the first thing to check: make sure you're releasing the trigger so it comes all the way forward. If you're not it will come to a place where the gun will be completely locked up when you try another pull. That's one reason Smith likes those awful full strength rebound slide springs on defense revolvers. Once you get used to the proper release it's no problem even in fast DA but it can sure slow you down when you're learning.

charles hit it right on the head...I didn't let the trigger go all the way forward (been shooting glocks too long) and the trigger locked 3/4 of the way back...

I cocked the hammer and it released...


initially, didn't know what the heck happened...but surmised it was me not letting the trigger go all the way back to reset.

glad to read here it was indeed shooter error and not my new beloved S&W