I have read ever post on this forum as to 9.3/72R carts. and have learned a lot of valuable info, however, I have become more confused. I have discovered there are 3 different chamber diments. I have not been able to find any info. as to their description. I also cannot get a good chamb. cast to determine case length, could this be due to lead fouling. I have spent 8hrs with every listed cleaner and still do not have what I consider a clean chamber. Pilgrim