Lead 12 Bismuth 27 steel 200 on the hardness scale.
Steel can not be flattened with a pair of pliers like Bis or lead.
Oh yea, that Tungsten stuff with iron, tin & moly to hold everything together...........on the hardness scale it is rated at 260 !!
Put a 3 1/2" load of "TTT's" through a full choke and see what happens
if they are so safe for old guns.
Apparently you are NOT familar with TungstenMatrix from Kent Cartridge Co. It is NOT the same as say TungstenIron from Federal and like products. Per the box:
"TungstenMatrix may be used in any nitro-proofed shotgun without fear of barrel or choke damage. Traditional lead choke constrictions and shot size recommendations apply."
I use TungstenMatrix in a 60+ year old, full choke, 16ga. Remington M31. It shoots and kills like lead.
I am NOT personally attacking you, Sagebrush, but you seem to be running TungstenMatrix together with steel and other much harder tungsten alloy products. From my understanding, Kent makes their product from a tungsten dust and polymar-type mix. Like Bismuth and lead, TungstenMarix is the only product SAFE to use in older guns.