Bi-based high-T_c superconducting monofilamentary and multifilamentary wires have been fabricated using a novel wire processing technique called "Continuous Tube Forming/Filling (CTFF)". In this technique loose superconductor powder is continuously fed onto a long silver strip which is then wrapped to encase the powder and form the wire. Improved superconductor core uniformity and largely reduced sausaging and cracking were found in CTFF-processed tapes due to a more uniform initial packing density and a reduction in the mechanical deformation required compared to PIT tapes. The heat treated CTFF tapes were characterised in terms of Bi2223 phase purity, microstructure, J_c and J_c behaviour in magnetic field. A J_c of 20,000 A/cm~2 at 77K and self magnetic field was achieved for 16-filament CTFF multifilamentary tapes.
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