.22 silencer with 1/2 x20tpi thread and now added 1/2 x28tpi

this is exactly the silencer I took from the source, and I just added a 1/2 x20TPI thread, it works I tested
I print this with black pla, 0.1 mm steps and 100% infill

now is a second model with 1/2 x28TPI I did not test it or print it myself