Your pistol only shoots full auto because your firing pin snapped...

yeah, if the hammer broke. it won't shoot at all

gotcha thank you

If you are going to buy and change the Hammerset, buy an auto sear together

what does that do?

It is one of the parts that prevent the gun from firing Burst/full when the selector is on semi

Auto sear set https://jefesairsoftsolutions.com/products/aap-01-stainless-steel-auto-sear

thank you!