Più che il tungsteno, che è troppo duro, direi il bismuto (con stagno ad almeno il 5%). Si, in usa ci sono già le borre:
Maurizio.

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pbTPS 28ga non-toxic shot wad preslit (100/bag) /b/p
pThe TPS 28ga is a full-length shot column wad design specifically for the rigors of modern non-toxic shot, like steel, ITX, and Hevi-Shot. Finally, a wad that will allow you to load almost any type of non-toxic shot for your modern 28ga shotgun. Designed for magnum field loads, the TPS 28 is the grand result of over two years of development. p
Maximum capacities of smaller shot sizes are 1 oz. ITX E-13 shot, 7/8 oz. ITX Original-10 shot, and 3/4 oz. steel shot. Capacity will vary greatly according to pellet size and these maximum weights will not necessarily yield the best loads; only testing results will render that decision.
p
Length = 1.770br
Depth = 1.632 br
Gas seal diam. = 0.546br
Gas seal depth = 0.085br
Wall thick. = 0.025 to 0.055 br
Slits = Four slits, 1.354 in length. pbody
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bProduct Type:/b Wad, Multi-Metal capability.br /
strongSize/strongb:/b 28-gaugebr /
bLoad data: /bSee load brochures. bbr /
Typical Loads: /bspan class=style1 /b28ga non-toxic and high-capacity field loads./spanbr /
bMaximum Payload:/bspan class=style1
/b1 oz. ITX E-13, 7/8 oz. ITX Original-10 shot, and 3/4 oz. steel shot. /spanbr /
bWARNING: i/bNo wad can protect every gun from every type of pellet risk or abrasion. Pellets harder than your gun's barrel can still cause damage. However, the TPS 28ga wad is molded in tough high density material and will provide maximum protection. bbr /
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Maurizio.
però vi posso dire che ci sono Aziende Italiane che stanno sperimentando con buoni risultati pallini in lega di ottone che sembrano assai validi e che non dovrebbero avere costi assurdi.
In bocca al Lupo
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