diff --git a/convert_hf_to_gguf.py b/convert_hf_to_gguf.py
index 916686838..0bf9b0fbc 100755
--- a/convert_hf_to_gguf.py
+++ b/convert_hf_to_gguf.py
@@ -3154,11 +3154,11 @@ class BambaModel(Mamba2Model):
         self.gguf_writer.add_ssm_conv_kernel(self.find_hparam(["conv_kernel", "d_conv"]))
         self.gguf_writer.add_ssm_state_size(self.find_hparam(["state_size", "d_state"]))
         self.gguf_writer.add_ssm_group_count(self.n_group)
-        self.gguf_writer.add_ssm_time_step_rank(self.find_hparam(["time_step_rank", "dt_rank"]))
         self.gguf_writer.add_ssm_inner_size(self.d_inner)
-        self.gguf_writer.add_ssm_head_count(self.find_hparam(["n_heads"]))
         self.gguf_writer.add_ssm_head_dim(d_head := self.find_hparam(["d_head"]))
-        self.gguf_writer.add_ssm_chunk_size(self.find_hparam(["chunk_size"]))
+        # NOTE: The mamba_dt_rank is _not_ the right field for how this is used
+        #   in llama.cpp
+        self.gguf_writer.add_ssm_time_step_rank(self.find_hparam(["n_heads"]))
 
         ## Attention params ##
         self.gguf_writer.add_attn_layer_indices(self._attn_layers)
@@ -3175,11 +3175,12 @@ class BambaModel(Mamba2Model):
         assert self.hparams.get("hidden_act") in [None, "silu"], "Only SILU activation supported"
         assert self.d_inner % d_head == 0, f"SSM inner size {self.d_inner} not a multiple of head dim {d_head}"
 
-        ## UNUSED?? ##
+        ## UNUSED ##
         #   "tie_word_embeddings" <-- Implied by presence of output weights
         #   "num_logits_to_keep"  <-- Always only keep final token logits
         #   "use_cache"           <-- KV Cache always enabled
         #   "use_mamba_kernels"   <-- I think this will always be true if available?
+        #   "chunk_size"          <-- This is used in the mixer implementation in transformers, but not here
 
     def modify_tensors(
         self, data_torch: Tensor, name: str, bid: int | None
diff --git a/gguf-py/gguf/constants.py b/gguf-py/gguf/constants.py
index 1db6e5a4d..166694a1f 100644
--- a/gguf-py/gguf/constants.py
+++ b/gguf-py/gguf/constants.py
@@ -151,9 +151,7 @@ class Keys:
         TIME_STEP_RANK = "{arch}.ssm.time_step_rank"
         GROUP_COUNT    = "{arch}.ssm.group_count"
         DT_B_C_RMS     = "{arch}.ssm.dt_b_c_rms"
-        HEAD_COUNT     = "{arch}.ssm.head_count"
         HEAD_DIM       = "{arch}.ssm.head_dim"
-        CHUNK_SIZE     = "{arch}.ssm.chunk_size"
 
     class HybridMamba:
         ATTN_LAYER_INDICES = "{arch}.attention.layer_indices"
diff --git a/gguf-py/gguf/gguf_writer.py b/gguf-py/gguf/gguf_writer.py
index 6e9c61d9d..d2cd1d531 100644
--- a/gguf-py/gguf/gguf_writer.py
+++ b/gguf-py/gguf/gguf_writer.py
@@ -790,15 +790,9 @@ class GGUFWriter:
     def add_ssm_dt_b_c_rms(self, value: bool) -> None:
         self.add_bool(Keys.SSM.DT_B_C_RMS.format(arch=self.arch), value)
 
-    def add_ssm_head_count(self, value: int) -> None:
-        self.add_uint32(Keys.SSM.HEAD_COUNT.format(arch=self.arch), value)
-
     def add_ssm_head_dim(self, value: int) -> None:
         self.add_uint32(Keys.SSM.HEAD_DIM.format(arch=self.arch), value)
 
-    def add_ssm_chunk_size(self, value: int) -> None:
-        self.add_uint32(Keys.SSM.CHUNK_SIZE.format(arch=self.arch), value)
-
     def add_attn_layer_indices(self, values: list[int]) -> None:
         self.add_array(Keys.HybridMamba.ATTN_LAYER_INDICES.format(arch=self.arch), values)