diff --git a/crates/ml/src/cuda_pipeline/gpu_dqn_trainer.rs b/crates/ml/src/cuda_pipeline/gpu_dqn_trainer.rs
index b72566d07..94bad02de 100644
--- a/crates/ml/src/cuda_pipeline/gpu_dqn_trainer.rs
+++ b/crates/ml/src/cuda_pipeline/gpu_dqn_trainer.rs
@@ -3256,20 +3256,20 @@ impl GpuDqnTrainer {
         // Extract raw pointers for online branch logits (contiguous [B, (B0+B1+B2)*NA])
         let on_b_base = self.on_b_logits_buf.raw_ptr();
         let on_b0_ptr = on_b_base;
-        let on_b1_ptr = on_b_base + (b * b0 * na * 4) as u64;
-        let on_b2_ptr = on_b1_ptr + (b * b1 * na * 4) as u64;
+        let on_b1_ptr = on_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let on_b2_ptr = on_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // Target branch logits
         let tg_b_base = self.tg_b_logits_buf.raw_ptr();
         let tg_b0_ptr = tg_b_base;
-        let tg_b1_ptr = tg_b_base + (b * b0 * na * 4) as u64;
-        let tg_b2_ptr = tg_b1_ptr + (b * b1 * na * 4) as u64;
+        let tg_b1_ptr = tg_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let tg_b2_ptr = tg_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // Online-next branch logits (Double DQN action selector)
         let on_next_b_base = self.on_next_b_logits_buf.raw_ptr();
         let on_next_b0_ptr = on_next_b_base;
-        let on_next_b1_ptr = on_next_b_base + (b * b0 * na * 4) as u64;
-        let on_next_b2_ptr = on_next_b1_ptr + (b * b1 * na * 4) as u64;
+        let on_next_b1_ptr = on_next_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let on_next_b2_ptr = on_next_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // N-step returns: use gamma^n for the Bellman projection.
         // The experience collector pre-computes R_n = sum(gamma^i * r_i).
@@ -3402,20 +3402,20 @@ impl GpuDqnTrainer {
         // Extract raw pointers for online branch logits (contiguous [B, (B0+B1+B2)*NA])
         let on_b_base = self.on_b_logits_buf.raw_ptr();
         let on_b0_ptr = on_b_base;
-        let on_b1_ptr = on_b_base + (b * b0 * na * 4) as u64;
-        let on_b2_ptr = on_b1_ptr + (b * b1 * na * 4) as u64;
+        let on_b1_ptr = on_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let on_b2_ptr = on_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // Target branch logits
         let tg_b_base = self.tg_b_logits_buf.raw_ptr();
         let tg_b0_ptr = tg_b_base;
-        let tg_b1_ptr = tg_b_base + (b * b0 * na * 4) as u64;
-        let tg_b2_ptr = tg_b1_ptr + (b * b1 * na * 4) as u64;
+        let tg_b1_ptr = tg_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let tg_b2_ptr = tg_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // Online-next branch logits (Double DQN action selector)
         let on_next_b_base = self.on_next_b_logits_buf.raw_ptr();
         let on_next_b0_ptr = on_next_b_base;
-        let on_next_b1_ptr = on_next_b_base + (b * b0 * na * 4) as u64;
-        let on_next_b2_ptr = on_next_b1_ptr + (b * b1 * na * 4) as u64;
+        let on_next_b1_ptr = on_next_b_base + (b * b0 * na * std::mem::size_of::<half::bf16>()) as u64;
+        let on_next_b2_ptr = on_next_b1_ptr + (b * b1 * na * std::mem::size_of::<half::bf16>()) as u64;
 
         // N-step returns: use gamma^n for the Bellman projection.
         let gamma = self.config.gamma.powi(self.config.n_steps as i32);