I never could get a decent knot tied although I was more than happy with the crimping method I used as Ranger described.

I did have a few early attempts pull thru but I found a "fix' for the problem that seems to work fine.

After you double the wire back thru the crimp sleeve. Use a pair of needle nose pliers sideways and  make the smallest 90 degree bend you can on tip of wire.

Make your loop and crimp. If you have some excess on tip above crimp ferrule, snip off flush as you can.
That little extra jamming against ferrule fixed the problem.