right - a model 12 will take anything except steel to my understanding

as i said- i have a few purpose built waterfowlers that have handled Kent TM with no issue

and LGF - the loads i use are all published loads - from the Lyman book, the Bismuth book from Ballistic products or the hodgdon website for 12 ga

for 10 ga i use loads developed and tested, among others - ones Sherman Bell published in DGJ - 10 ga loads have been collected on the Parker collector's pages in the reloading forum