I usually have a bullet in mind when I start thinking about load development.Recently,I pretty much built a rifle around one bullet,and was thrilled when the rifle actually liked that bullet.In these crazy times,I was even more thrilled when I found out that it likes just about every 7MM bullet I've tried in it.
What kind of gun it is,what I want to do with it and what is available for it are a few things that influence how I go about working up a load.In most cases,I do some research if it's a round that I've never worked with before.I read any load data I can find,I check out what guys on this site and a few others have done and then I start to choose components.
I usually try a few of the best powders with the best(on paper)bullet,shooting 3 shot groups at the starting load for each powder.I usually get enough from this to get a start on the next step,which is more 3 shot groups with a gradual increase in charge weight,and maybe I'll start to tinker with overall length a little bit,but I don't put near the emphasis on COAL that I used to most of the time.I like to use bullets that are as forgiving as possible as far as seating depth is concerned.Once I feel like I'm getting something roughed out,the chronograph comes into play.I use to check for abnormally high or low velocity as well as spread.I think it's worth the effort to use one,especially if I want the best accuracy,and I also use velocity readings to help me decide when I'm at the max for that load in that gun.No point in dumping more powder in when it doesn't gain anything more than a bigger muzzle flash.
At this point,I've found a powder type and charge weight that I'm happy with.I've given up on the idea that a tenth of a grain of powder in either direction will give fantastic results.If a load's walking on that razor's edge,I'll keep digging.A change in temperature or elevation can change it enough to make it no better than a more forgiving load.I like to use powders that are less sensitive to temperature change,and I've found some powders that aren't all that popular are very good in this respect,especially some of the Enduron powders from IMR.
Even after I've settled on a load,I'll still keep taking a few rounds of something different with me when I'm shooting just to make sure I haven't missed something.In these times of tight supply,I think it's good to have more than one combination to work with if at all possible.Experience is also very valuable.I have a few 308's,and when I'm starting out with of those,I already have a good idea what's going to work.I don't think there's anything more important than keeping some kind of log on every rifle I have,and some of my customers' rifles as well.I even go so far as to keep the targets themselves to go back and look at.
I can't say that I follow one set in stone regimen for load development,I guess it's more like I have some guidelines that I follow,and I change a little as I feel the need t
ne thing I do follow is I try to get the most velocity I can without giving up accuracy and/or safety.It would not be good to need a second shot and have a locked up action.