I've been trying to run sslstrip and have followed tutorials step-by-step and come back with the same results - Dump files that are blank. I've tried taking out the mitm steps too, to simplify the attack against my own machine and still have the same problem.

This seems self-explanatory:
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A PREROUTING -p tcp --destination-port 80 -j REDIRECT --to-ports 10000
cd /pentest/spoofing/sslstrip
python sslstrip.py -w dumpfile
I've ran nmap to ensure that sslstrip was running on 10000
10000/tcp open  snet-sensor-mgmt
It even saves a dumpfile, but after logging in and out of sites I hit Ctrl+C to close sslstrip, open the dump file I saved with either cat or a text editor and there is absolutely nothing inside the file?