That would depend on who made the barrel.
If you get up to 1/2 the weight of the ball I'd recommend you start over. Review the groups you've shot, pick the best and look at ball size and/or patch thickness. My loads are based on historic loads used for the same rifle. As was said previously, every gun is different and even two factory made guns with consecutive serial numbers may be different. Everything said here is just a starting point.
This whole process also gives you a chance to get thoroughly familiar with your rifle and gives you the confidence to know that if after you finish and you miss your target it is you not the rifle or load.