what went wrong

[charlie cleveland]

i was shooting some 3 1/2 in 10 ga loads today.the gun i was using was a ithaca mag. ten auto. ishould have stated these were reloadsthat ihad reloaded myself.they were reloaded by the manul andall things done right to my knowledge. the shells shot ok but the brass at base of shellsplit on 6 rounds right were the outer edge of the rim.the last round that i shot the plastic of the shell stayed in the chamber. the brass had come off theshell completely. i then went and got 3 new shells ihad not noticed as of yet that the plastic was still in the barrel. i tryed to chamber a round but it would not chamber this is when i noticed the plastic hull still in barrel. took a while to get it out with a long rod.this was kind of a scarey thought if that plastic had ofwent up the barrel a little faruther and round had chambered.... has any one ever had this to happen to them. or any body got any ideas to what caused this. i haved decided to get me a 3 1/2 double barrel to shoot my reloads in anduse onlyfactory loads inthe automatics.... my reson for doing this is be cause you can see down the bore of a double a lot easyer than you can of the auto.. hope someone has got some answers... thanks charlie