Good to hear you survived joe
BUT people do get their faces blown off from time to time through a variety of reasons which is 99% of the time operator error
Anyway seeing your a machinist you would appreciate gauges & how essential they are, from day 1 of my reloading adventure some 15 years ago I researched all the gear I needed to make the most accurate ammo I could, even for hunting.
So things like headspace gauges, comparators & OAL gauges are a must for any serious handloader who wants to obtain small groups.
You need headspace gauges to be able to set up your dies correctly, OAL gauge to know how far off the lands you are (in conjunction with the comparators) & be able to change that during the LD stage, your CBTO plays a major roll in shrinking groups imo.
Where to start, well for me it depends on the spread of the powder charge, sometimes there can be 5gr from min yo max so then I go .5 increments, sometimes if there is 4gr or less(sometimes there is 3.5gr!) I will then go .3 increments.
This is my usual process from another thread-
I start all my LD regimes at 10 thou CBTO, find the node/s then change my CBTO to 5 thou & to 15 & 20 with the best performing charge, never had to go any further before finding the perfect depth, if I get very close to where I want to be at a set depth then I will also do small incremental powder charge changes of .1gr either side of that.
That's my method anyway, I usually have a result within 40 rounds, if I haven't I swap powders OR scrap that projectile which I rarely do but have only had to do that twice(more about the stability factor really) when loading for 7 different cartridges & up to 3 or more projectile types in a single rifle but I have never ventured more than 20 thou.
Also Joe, if you haven't already done so there is some great info in here in other existing threads, use the search button as it a great resource to have at your finger tips!
Here's some threads you might get something from-
https://www.longrangehunting.com/threads/what-is-your-reloading-process-from-start-to-bang.221646/
https://www.longrangehunting.com/threads/case-prep-question.222545/#post-1664035
https://www.longrangehunting.com/threads/seating-depth-limitations.219425/page-2#post-1625089
https://www.longrangehunting.com/threads/bullet-touching-the-lands-or-2000th-back.222901/page-2
https://www.longrangehunting.com/th...king-for-feed-back.219865/page-4#post-1631096
https://www.longrangehunting.com/threads/bullet-off-lands.218153/
Good luck in your quest
Edit: While I don't suggest or promote it I also go slightly over max book loads in my work up by up to 1gr, obviously keeping a close eye on the pressure signs & stopping if something does not look or feel right.
Quite often you can & do find more that 1 node & 1 can be in this higher range.
If you have decent brass you generally find that you get less or zero pressure signs even at 1gr over.*GENERALLY speaking most reloading data is slightly on the conservative side, for your safety & so I guess there are minimal law suits