Pressure. Lead is softer and “gives” under pressure.
Possible barrel scoring. Wads for TSS are normally much thicker and/or use a tyvex wrap.
Volume. Lots of TSS loads require some filler to occupy space as TSS is denser than lead.
Possible choke issues. TSS normally requires open chokes.
Patterns. May be better. May be worse. Crapshoot.
For starters ...
That said, I know guys who will replace 1/8 or 1/4 oz in heavy lead or heavy steel loads.
I will load tss/steel duplex from scratch but the limited pattern testing I have done has lead me to no firm conclusions.
You’d be amazed what TSS has done to the smaller gauges.
"What we obtain too cheap, we esteem too lightly: it is dearness only that gives every thing its value. Heaven knows how to put a proper price upon its goods; and it would be strange indeed if so celestial an article as freedom should not be highly rated." Thomas Paine
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