BuckMark sear spring flip fail.

[Fat Old Mopdog]

['ol shooter]

Sometimes it works, sometimes it doesn't.
My 1985 with the original spring flipped comes in at a reliable 2 1/4 lbs. It has not failed after many hundreds of rounds. Many newer owners report the same results as you did.
The best way is the new spring from Tandem Kross, which is a drop in unit encased in a plastic box, reports are very good.

https://www.tandemkross.com/

Rim Fire Central is the go to for all things rimfire.

http://www.rimfirecentral.com/forums/

[Fat Old Mopdog]

Copy that sir. The TK box is $30. Thought I might luck out on the cheap.

[Strafer]

+1 for the Tandem Kross unit. I put it in my Buckmark. Easy, and it works quite well. I also put on a Vortex Venom 3moa. It is a very accurate and fun squeak dispatcher.

[broadside]

I have the TK Gearbox in my Buckmark and its nice. Install is super simple. I did not change the trigger feel too much though for me, but my gun was a pre-93 model with a lot of use so the factory spring could be weaker already

[Packy14]

Personally the buckmark was just too fragile, between self stripping take down screws to barrel cant problems... ultimately I had to buy a real .22 (ruger MKIII).

[newbie1234]

I had the Regis flips on my two Buckmarks and they both below #3 trigger pull, very happy with that. Then one day did the experiment of: SLIGHTLY stoned the sears and hammers and polish all the moving parts + interface surfaces of sears and hammer, removed the magazine disconnetor, flip back the sear spring to the way it was and got #2.5 trigger pull and they are in that configuration until now.
During the time I had the Regis flip sears springs on my two Buckmarks I shot about 3K-4K each , no problem at all.

Notes: I just remembered that for reassembly the pistol, I installed first the sears spring, then the sears, last is the hammer or something liked that. The things for sure is to install the sears spring FIRST.