DX11 vertices not drawn over a certain number - c++

Question

I'm trying to render a fullscreen tessellated mesh. It works as expected for up to around 250x250 vertices, but past that, it cuts off after the top half or so (depending on how tessellated I set the mesh).
I have a vertex and index vector, which I populate programmatically as a trianglelist. I suspect it might be related to the buffer size of the vertex buffer, since the number of vertices/indices seems right, but when I try to increase the bytewidth allocation, I get a memory access violation.
The vertex data struct defined as such:
struct SimpleVertex
{
XMFLOAT3 Pos;
XMFLOAT2 Tex;
};
To initialize the buffers, I use:
D3D11_BUFFER_DESC bd;
bd.Usage = D3D11_USAGE_DEFAULT;
bd.BindFlags = D3D11_BIND_VERTEX_BUFFER;
bd.CPUAccessFlags = 0;
...
D3D11_SUBRESOURCE_DATA InitData;
InitData.pSysMem = &(meshVertices[0]);
...
D3D11_INPUT_ELEMENT_DESC meshLayout[] =
{
{ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 },
};
Vertex buffer:
...
bd.ByteWidth = sizeof(SimpleVertex) * (UINT)(meshVertices.size());
...
hr = g_pd3dDevice->CreateBuffer(&bd, &InitData, &g_pMeshVertexBuffer);
Index buffer:
...
bd.ByteWidth = sizeof(WORD) * (UINT)(meshIndices.size());
...
hr = g_pd3dDevice->CreateBuffer(&bd, &InitData, &g_pMeshIndexBuffer);
Draw call:
void RenderMesh(){
g_pImmediateContext->OMSetRenderTargets(1, &g_pRenderTargetView, g_pDepthStencilView);
UINT stride = sizeof(SimpleVertex);
UINT offset = 0;
g_pImmediateContext->IASetVertexBuffers(0, 1, &g_pMeshVertexBuffer, &stride, &offset);
g_pImmediateContext->IASetInputLayout(g_pMeshVertexLayout);
g_pImmediateContext->IASetIndexBuffer(g_pMeshIndexBuffer, DXGI_FORMAT_R16_UINT, 0);
g_pImmediateContext->VSSetShader(g_pMeshVertexShader, nullptr, 0);
g_pImmediateContext->PSSetShader(g_pMeshPixelShader, nullptr, 0);
g_pImmediateContext->PSSetSamplers(0, 1, &g_pSamplerLinear);
g_pImmediateContext->DrawIndexed(numMeshIndices, 0, 0);
}
Any help would be greatly appreciated.