A buddy of mine recently bought himself a Model 66, 4 inch. Its a gorgeous gun in perfect shape.. almost LNIB.. turnline is very very faint. I'd guess less than 100 rds thru it. Its a prelock so I guess its pre mid 90s? He knows that these revolvers are marked as .357 Magnum... he also knows unlike the 686 or the GP100 that they are know to wear hard if fed a lot of full power .357 Mag Ammo and that training is supposed to be in 38SPC with these Kframes. He has some 38SPC in 130 gr +P on hand but not a lot.. So his question to me as his usual gun-guy is (which I cant answer on my own). what kind of 357 Magnum ammo is safe not just for carry, but also if he wants to train hard and put 200-300 rds thru it in an afternoon. ...most of his Ammo stock is this 142 gr Fiocchi Ammo which claims 1420 fps and 636 ftlbs of energy (not sure reference barrel length ..probably long) He has plenty of it. https://www.midwayusa.com/product/100024278 But I know this ammo.. It may not be the hottest factory load you can buy but its definitely up there and pretty hot. Question he has is this Ammo safe to shoot in volume out of his Model 66? Not for carry but just for training... Or should he spend money for 38 SPC and/or a milder training 357 Mag (if so which ones? perhaps a 158gr thats slower and the longer bullet will reduce the flame hitting the FC? ) What do you guys think?