[en] An approach to overcoming the problem of dynamic conversion in high-mobility bubble garnets is described based on large gyromagnetic ratios (high-g factors). In a film of Eu₁.₄₅Y₀.₄₅Ca₁.₁Fe₃.₉Si₀.₆Ge₀.₅O₁₂, a g factor greater than 30 has been obtained, which increases the usable domain wall velocity before onset of dynamic conversion by more than an order of magnitude over comparable bubble garnet films with g approximately 2. The temperature dependence of the important bubble parameters has been measured and a simple bias magnet constructed which matches the steeper than usual variation of the bubble collapse field with temperature. Two different methods of hard bubble suppression are described, one involving short oxygen anneals at approximately 1050⁰C, and the other ion implantation