Howdy
This is a well known problem. The pin can jump forward under heavy recoil and then the transfer bar can catch on the firing pin as the hammer is cocked.
There are three solutions.
1. Replace the latch spring with a heavier one.
2. Replace the pin with one from Belt Mountain.
3. Fit the pin better to the latch.
I generally go for a combination of 2&3. I have not put stronger springs in any of my Rugers. They all have Belt Mountain pins in them, my 2nd Gen Colts do too. And I usually do a little bit of fitting so the latch fits the slot in the pin properly.
By the way, I do not recommend the Belt Mountain pins with the little set screw. You need to keep the tiny allen wrench handy if you ever want to remove the pin, and if you tighten it too much you can bend the pin slightly, which causes the cylinder to bind. Ask me how I know this.
I just use the standard Belt Mountain pins without the set screw and do a little bit of hand fitting.
Try this test. Remove the cylinder and cylinder pin. Push the latch all the way in then let it go. It should snap all the way home.
Then reinstall the cylinder and pin and repeat the test. Did the latch snap all the way home? Did it hang up a bit? Did it stop partway?
If it does not snap all the way home, replacing the spring is a band aide approach. The pin needs to be properly fitted to the latch. With the pin properly fitted, a stronger spring is not needed.
Rugers are mass production guns and a lot of times the latch does not fit the pin properly.
That's why I use Belt Mountain pins. The retaining slot is a horizontal cut across the pin, not an annular ring like most Rugers. A horizontal slot presents more surface area to the latch, and a horizontal slot can be fitted because the pin always has the same orientation every time it is popped in place.