I'm not completely understanding what you have lisetd so let me ask this;
1) Caps are not igniting all the time when struck by hammer. ... Right?
2) Caps are igniting when struck by hammer but main charge is not .... Right?
Sorry for phasing it this way but I just don't get what it is doing or not doing. Sounds to me like you have taken care of the practicals and perhaps you might have a bad nipple. Look at the cup of your hammer. That is the part that strikes the caps. What do the fresh marks look like; a horseshoe, C print or circle, O ?
This can be fixed. ... !!
Be Safe !!!