diff --git a/renderdoc/driver/d3d12/d3d12_device_wrap.cpp b/renderdoc/driver/d3d12/d3d12_device_wrap.cpp
index 3c6fda41f..20b1b7e9f 100644
--- a/renderdoc/driver/d3d12/d3d12_device_wrap.cpp
+++ b/renderdoc/driver/d3d12/d3d12_device_wrap.cpp
@@ -847,6 +847,40 @@ void WrappedID3D12Device::CopyDescriptors(
 
   RDCUNIMPLEMENTED("CopyDescriptors does not copy our internal descriptor data");
 
+  UINT srcRange = 0, dstRange = 0;
+  UINT srcIdx = 0, dstIdx = 0;
+
+  D3D12Descriptor *src = GetWrapped(pSrcDescriptorRangeStarts[0]);
+  D3D12Descriptor *dst = GetWrapped(pDestDescriptorRangeStarts[0]);
+
+  for(; srcRange < NumSrcDescriptorRanges && dstRange < NumDestDescriptorRanges;)
+  {
+    dst[dstIdx].CopyFrom(src[srcIdx]);
+
+    srcIdx++;
+    dstIdx++;
+
+    // move source onto the next range
+    if(srcIdx >= pSrcDescriptorRangeSizes[srcRange])
+    {
+      srcRange++;
+      srcIdx = 0;
+
+      // check srcRange is valid - we might be about to exit the loop from reading off the end
+      if(srcRange < NumSrcDescriptorRanges)
+        src = GetWrapped(pSrcDescriptorRangeStarts[srcRange]);
+    }
+
+    if(dstIdx >= pDestDescriptorRangeSizes[srcRange])
+    {
+      dstRange++;
+      dstIdx = 0;
+
+      if(dstRange < NumDestDescriptorRanges)
+        dst = GetWrapped(pDestDescriptorRangeStarts[srcRange]);
+    }
+  }
+
   SAFE_DELETE_ARRAY(dstStarts);
   SAFE_DELETE_ARRAY(srcStarts);
 }
@@ -863,16 +897,7 @@ void WrappedID3D12Device::CopyDescriptorsSimple(UINT NumDescriptors,
   D3D12Descriptor *dst = GetWrapped(DestDescriptorRangeStart);
 
   for(UINT i = 0; i < NumDescriptors; i++)
-  {
-    // save these so we can do a straight copy then restore them
-    WrappedID3D12DescriptorHeap *heap = dst[i].samp.heap;
-    uint32_t index = dst[i].samp.idx;
-
-    dst[i] = src[i];
-
-    dst[i].samp.heap = heap;
-    dst[i].samp.idx = index;
-  }
+    dst[i].CopyFrom(src[i]);
 }
 
 HRESULT WrappedID3D12Device::OpenSharedHandle(HANDLE NTHandle, REFIID riid, void **ppvObj)
diff --git a/renderdoc/driver/d3d12/d3d12_manager.cpp b/renderdoc/driver/d3d12/d3d12_manager.cpp
index 04dfa0ee9..e1f3d08d3 100644
--- a/renderdoc/driver/d3d12/d3d12_manager.cpp
+++ b/renderdoc/driver/d3d12/d3d12_manager.cpp
@@ -145,6 +145,18 @@ void D3D12Descriptor::Create(ID3D12Device *dev, D3D12_CPU_DESCRIPTOR_HANDLE hand
   }
 }
 
+void D3D12Descriptor::CopyFrom(const D3D12Descriptor &src)
+{
+  // save these so we can do a straight copy then restore them
+  WrappedID3D12DescriptorHeap *heap = samp.heap;
+  uint32_t index = samp.idx;
+
+  *this = src;
+
+  samp.heap = heap;
+  samp.idx = index;
+}
+
 D3D12_CPU_DESCRIPTOR_HANDLE Unwrap(D3D12_CPU_DESCRIPTOR_HANDLE handle)
 {
   if(handle.ptr == 0)
diff --git a/renderdoc/driver/d3d12/d3d12_manager.h b/renderdoc/driver/d3d12/d3d12_manager.h
index 18ba5a241..d33654eb6 100644
--- a/renderdoc/driver/d3d12/d3d12_manager.h
+++ b/renderdoc/driver/d3d12/d3d12_manager.h
@@ -149,6 +149,7 @@ struct D3D12Descriptor
   void Init(ID3D12Resource *pResource, const D3D12_DEPTH_STENCIL_VIEW_DESC *pDesc);
 
   void Create(ID3D12Device *dev, D3D12_CPU_DESCRIPTOR_HANDLE handle);
+  void CopyFrom(const D3D12Descriptor &src);
 
   union
   {