cracking seeds that wont germinate

so i have these seeds i made myself and their the biggest seeds i have ever seen/had but they wont germinate after 4 days(paper towel method and socked for 12 hours). so i cracked one open and she looks beautiful nice and healthy nice and white. is it possible that the shell is to hard and they might need a little help getting out? what do you guys recommend i do in this situation?
thanks

My buddy cracks all of his,but i just soak em till they drop to the bottom of the Glass.

Now socked like punching them,LOL.Dont know.

Beech

Some crosses and strains will need curing time in order to crack .. If they are still fresh chances could be such but you described them as thick and hard so it may just be a case of scuffing them before the soak . I have some hard Indica beans that require this in order to grow .. Crack at your own risk . Seen too many beans ruined that way

thanks guys

I had problems with Cole Train (reserva privada). Found a site that said to use emory board and thin down the area where the tap root comes out. I accidently cracked a C99 (tiny crack visable only by magnification) after only 9 hours of soaking in water the inside swelled up and I put it directly in the dirt and it worked. Only problem is that cracking a bean on purpose with such a small crack would take some practice...so Im going to stock up on bag seeds if given the opportunity.