Originally Posted by
Les Pepperoni
^^ That's some good advice, right there.
My advice:
1.) Select a bullet weight and powder combination that you know will work.
124's? OK. Titegroup? OK. (personally, I've seen a bit too much smoke outta TG and SNS's old Gold coating... They had a bad batch a bit ago...)
2.) Select a decent OAL and stick with it, 1.110"-1.120" sounds alright.
3.) Start at .6 under the average powder charge and work up to just .2 over. 4.0Gr seems ok. 3.4, 3.6, 3.8, 4.0, 4.2.
Load ~20 of each. Shoot the first 12, in groups of 3, off of bags at a 15-20 yard target with a consistent aim point. (E.g. you want to evaluate the "group", not your accuracy.) The charge that gives you the tightest group for that bullet weight and OAL is probably what you want to load with.
Pull one pc every 5-6 loadings and check that the powder drop is giving you a consistent charge drop.
4.) Shoot the next 8 from each charge grouping in groups of 4, offhand and evaluate the feel, recoil, etc. It might be that the most accurate load is too much. If so, just compromise and take the next lowest bracket.
5.) If you're shooting IDPA or USPSA, get a chrono and check that you're pet load is making PF.
My experience:
I've found that some of the low-volume, quick burning powders have a sweet spot. Just bumping the charge up or down a notch for your bullet could make a big difference. Hence loading the "spread" of charges. It is nice too - you get in, get done, get data quickly.
Some known good loads:
HP38 and a 147.
WST and a 124 moly.
AA2 or AA5 and 124 or 147's
Anything Vihtavouri.
You'll find that some of the slower powders may produce better groups, but most of those are too "stout" where you begin to notice it.
I mean, 6.5gr Power Pistol in a 115gr 9mm is amazingly accurate, blasty as hell and is just barely making power factor for USPSA.