Cold emailing: 60% open rate and 20% response rate

Today was a very productive day and I started to test cold emailing on a small scale, I've sent only 10 emails so far, just to test things our before I start automating.
So far I got

• 2 responses
• 6 people opened their emails.

After the 2 responses:

• With one person we've exchanged a few messages, and he seems to be interested in our product.
• From the second person I got their Skype ID and I'm waiting for their response.

Other things I managed to do:

• I fixed some small bugs
• Made it faster by upgrading the server and running more threads.