TargetTalk

Does somewhat with more experience than me with the Hammerli 280 in .22LR know if the the most usual reason for light strike misfires is: (1) needs cleaning, (2) needs lubrication, (3) needs different ammo (4) needs new firing pin, (5) needs new firing pin spring, (6) something else?

1/ Clean and brush chamber.
2/ Remove, inspect and clean firing pin and firing pin channel. lube
3/ Consider a new Hammer spring.

Friend of mine had to change the barrel (in his case).

In my experience with my 280 it's because it needs cleaning. Somewhere between 500 and 1000 rounds I will start to get light strikes because powder builds up on and around the firing pin.... a toothbrush with some cleaner will solve that issue on the firing line.. and then a proper cleaning at home.

For Ammo I have used CCI Std Velocity and have had no issues with reliability other than the above mentioned dirty firing pin.

When I am diagnosing a .22 problem, the first thing I do is verify that a new round will fall into the chamber and seat against the rim. If a round stops short of fully seating against the rim, that can be a cause of light firing pin hits, as the energy of the firing pin strike is used to push the cartridge into the chamber the rest of the way rather than denting the rim.

Although I shoot a sp20 and not a 280 I had light strikes with Eley ammo.
After contacting the factory they mentioned their rim thicknes is 2.5 thou thinner than some other ammo.
If you dont use Eley ammo, disregard my remark.

David M wrote: ↑Wed Oct 16, 2019 12:26 am 1/ Clean and brush chamber.
2/ Remove, inspect and clean firing pin and firing pin channel. lube
3/ Consider a new Hammer spring.

As I said, do the above, and because the pistol is between 20 & 30 years old, fit a new Hammer spring.
Can easily be made from Wolf Spring blanks (use same OD and wire dia.) Remember old springs compress.
Use the maximum length possible without coil bind (when cocked).
The firing pin spring should be OK as all it does is pull the firing pin back after firing.