I got this achievement recently. I was using the M5 Stuart which is a Tier 4 Light Tank. I managed to get this against a random player who was using a Grillie Tier 5 Artillery.
Here is a clip showing that I did it.
I managed to get this by shooting the enemy just before I rammed him. I didn't even realise this was an achievement until I got it. Started playing this game again recently.
Light tanks with high top speed are a good option such as USA or Russia. Artillery are good targets to try and ram.