Take care with the trigger!!

[DavidS]

Today I was shooting one of my 2289's and the sear stopped engaging the hammer.   first I checked that the spring was still in place, and it was, then I checked that the sear would still engage the hammer and it would.   The problem ended up being my weakened trigger spring, it was not pushing the sear far enough to engage anymore.

So if you tune your trigger on the 13xx platform be careful to have extra springs .   That could have been dangerous.

[D14Jeff]

i compressed my stock hammer spring till it wouldn't hold the hammer when cocked ..... then (a little at a time) i stretched it back out till with the safety off and cocked i could beat the grip on a carpeted floor without it firing . much lighter and still safe polishing the trigger and sear contact with some toothpaste on a Q-tip with a drill helped make it smoother too .

[rangerfredbob]

I've tuned the trigger spring on all of my 13XX and 22XX guns (all 7 of them) by just compressing the spring, it doesn't take much... just squish it til there is about 1/8" preload on the spring. Since it's a fairly soft spring steel it's easy to bend, I'm not sure why everyone insists on cutting them...

[DavidS]

i compressed my stock hammer spring till it wouldn't hold the hammer when cocked ..... then (a little at a time) i stretched it back out till with the safety off and cocked i could beat the grip on a carpeted floor without it firing . much lighter and still safe polishing the trigger and sear contact with some toothpaste on a Q-tip with a drill helped make it smoother too .

same thing I did 6 months ago, the spring finaly weakened enough to be a problem yesterday.

[BigTinBoat]

I'm not sure why everyone insists on cutting them...

I'm no engineer, but have been told that cutting the spring is better then "over compressing". Once you over compress it you weaken it and change the dynamics. A cut spring will just be shorter with the same compression/rebound rate. Best to get the spring length you need with more/less coils and different diameter wire to change the rate.

[breakfastchef]

Always 'bump test' your airgun after making changes to the sear spring and trigger group. This helps you ferret out potential problems with misfires or inadequate sear engagement. Unfortunately, sometimes it take several rounds down range before the problem surfaces, so always shoot safe.

[vigilandy]

Always 'bump test' your airgun after making changes to the sear spring and trigger group. This helps you ferret out potential problems with misfires or inadequate sear engagement. Unfortunately, sometimes it take several rounds down range before the problem surfaces, so always shoot safe.

Yeah,  and don't be stupid and do the bump test under your covered patio.  Had a brain dart,  and was lucky the stock AR2079 waa only pushing 500fps. Made a nice dent in the vinyl roof panel,  but no hole!

[rangerfredbob]

I'm no engineer, but have been told that cutting the spring is better then "over compressing". Once you over compress it you weaken it and change the dynamics. A cut spring will just be shorter with the same compression/rebound rate. Best to get the spring length you need with more/less coils and different diameter wire to change the rate.

I am an engineer... when you shorten a spring by cutting it you effectively stiffen the spring rate a little bit. The sear spring on these things is pretty cheesy, I doubt it's very heat treated as it doesn't require much force to compress it, and you aren't changing it very much anyway. It might weaken the spring a little by compressing it, but it probably takes the life down to 10,000 cycles from 20,000 cycles or something silly...

[BigTinBoat]

I am an engineer... when you shorten a spring by cutting it you effectively stiffen the spring rate a little bit. The sear spring on these things is pretty cheesy, I doubt it's very heat treated as it doesn't require much force to compress it, and you aren't changing it very much anyway. It might weaken the spring a little by compressing it, but it probably takes the life down to 10,000 cycles from 20,000 cycles or something silly...

But you don't "actually" stiffen the spring rate, right? I know the "Effect" would be a perceived increase (stiffening) as it is traveling a shorter distance, but the actually spring "stiffness" itself is unchanged.

Wouldn't you, as an engineer, say that the "best" way to "lighten" the trigger pull would be to get a spring with a "weaker" force?

I think David has shown that he did "weaken" the spring to an unusable one within 6 months.....can it be repaired? likely the answer is yes , by stretching,  but then the same problem will also likely occur, right?

[D14Jeff]

if my compressed hammer spring weakens a few times a year i'll just take it out , stretch it a bit to get the tension i want again and i'll be good to go . so far mine is still fine though . but i like tinkering and i love cheap/free

i'd be concerned about the engineering stuff mentioned here on the power spring on a springer airgun ....... but not the springs on my pumper because it's so dang easy (and fun) to take apart and tinker with . i am a novice at this though .

[rangerfredbob]

Yeah, I'd have to look back in my books to get into full detail as I don't remember everything...

Yes, you are right, the effective spring rate is greater, but the preload is lower so the perceived spring force is less when you cut the spring... two reasonable ways to get the same result.

For a springer gun things get more complicated as the forces on the spring wire are much greater and near the yield point of the metal, the sear spring on these pistols is ~1.5" long and the sear travels ~1/8" with 1/8" of preload, that's a lot different than on a spring gun where the free length is say 12", 2" of preload and say 5" of compression when cocked.

To sum it up, the sear spring isn't stressed much and shouldn't really fatigue, but do a bump test on all trigger mods, and keep note if the trigger pull starts getting easier no matter what method you use, which is what the OP was going for