thanks for the input...I just took it apart, and the piston seal did have a little chunk torn out of one edge. there was a burr in the compression tube slot. You'd think whoever puts these together could take 20 seconds to file/sand the slot before inserting the piston.
before this happened, I could also, if I did my part and the SD wind wasn't blowing, shoot dime sized groups out to 35 yds. hopefully I can, again.