Are the PSA 3.5lb curved bow trigger springs upgradable?

[robholland1911]

I have been using the PSA Custom Series 3.5 curved bow trigger in my two KS-47s, one is a factory 10.5" pistol and the other is a 16" rifle I assembled out of various parts. Both use PSA KS-47 lowers and enhanced firing pins, in addition to the PSA Custom triggers. I only recently installed the trigger in the 16" and have fired, maybe, two magazines through it (without issue), and just installed the trigger in the 10.5", with no rounds fired until today. And then the issues started.

So, I take both out today to run some rounds. After just a few rounds out of each I start getting light primer strikes on the steel cased ammo I was using. I know the primers are harder, which is why I run the enhanced firing pins, but I have not had an issue with this using the older original triggers. I was lucky enough to have a friend give me some brass cased S&B to try and every round of that fired perfectly.

My guess is that the hammer spring is not strong enough to ignite the primers. I have heard that the springs in these Custom Series triggers are replaceable but was hoping to ask if anyone on the forum knows for sure. It’s my understanding that replacing the hammer spring should not increase the trigger weight, am I right here? One last point, the hammer spring loop (the part that contacts the back of the hammer) has a 45 deg kick to it, is this common and are there replacements (heavier weight, of course) that I could purchase and replace it with.

I appreciate any help, as I love these triggers and really hope I can find a way to use them.

[GuitarGuy]

While i have not run into your issues, i do know folks that use Wolff extra power hammer springs because they mostly shoot steel. You might want to try that. They are available at most major gun part retailers.

[Xterra9171]

Replying to see what the outcome is.

I know wolf offers extra power springs like mentioned above. Hiperfire does too.

[robholland1911]

Well, the trigger definitely comes apart, but my concern is that because of the shape of the back of the hammer, the spring has to have a slight bend to it. I suppose I can simple buy a heavy power spring, but I was hoping someone might know of a manufacturer that makes one already bent. This is what it looks like.

[daveg1184]

Now I see what your talking about I’ve been looking and haven’t seen any replacement springs with that bend in them. Has anyone asked psa what they recommend I’ve tried getting in touch with a actual person over there with no luck

[LoneGunMan]

Bend the current spring you have or use another in a vise. You want to bend the forks outward so you get more tension on the hammer. I have already done it and works great.