This paper studies debt-target reforms in a small open overlapping-generations economy with endogenous external spreads and productive public capital. We extend a tractable two-period benchmark to a finite horizon life cycle model with public debt and exact cohort welfare accounting. Lower debt targets can raise long-run growth while still imposing sizable welfare losses on cohorts alive at the reform date, and these effects operate mainly through human wealth and the consumption-scaling factor rather than financial revaluation. The open-economy margin is quantitatively important because reforms change the equilibrium path of net foreign liabilities and hence spreads and domestic interest rates, which materially shape both transition dynamics and cohort welfare.