I recently "inherited" my father's Security Six in .357 magnum with 6 inch barrel (ported by a local gunsmith). It's mostly had .38 specials fired through it. I was loading up some of Speer's 155 grain lead SWC bullets (.358 diameter) for it the other day and decided to try the Elmer Keith push through test for the cylinder throats. There was no way the bullets could pass through those tight throats. This got me thinking about my experience at the range the other day. I had loaded the 155 grain LSWC behind 4.7 grains of Unique for a low end +P 38 Special load. I was a little surprised by the amount of recoil inspite of the ported six inch barrel. I've fired a .45 Colt Vaquero as well as an M&P .45 ACP and the recoil of the .38 seemed to be quite a bit sharper than either of these. I began to wonder if the tight throats are generating higher than normal pressures. Does anyone have any knowledge of excessively tight cylinder throats in the Security Six?