suppressor

I have a suppressor that can handle .22lr and .17hmr. I have found that firing supersonic .22lr is almost as loud as firing un-suppressed due to the sonic boom. Sub sonic .22lr is very quiet, but has a terrible drop rate - I have to adjust my scope for even small distance changes I am...

I live in Texas and I am looking at purchasing a suppressor for my sig sauer p229 that is chambered in 40s&w. The problem I have is finding a threaded barrel for this model and caliber. Any suggestions on where to look?