I highly recommend watching the
Precision Handloading - What REALLY Matters? video series on Little Crow Gunworks's YouTube channel. Playlist link here:
https://youtube.com/playlist?list=PLoeioEp8focRcyTvAqt5m_-9shU0xcH44&si=BZxzBqjFwM10-myX
It is the most thorough step-by-step presentation out there on handloading for accuracy. I think Adam does a really good job of prioritizing what things matter the most, versus things that might also improve accuracy, versus minutia that only matter if you're already consistently shooting 1/3 MOA groups. He discusses some important principals had identified on my own and I've not heard, seen, or read elsewhere.
It would be best to watch all 17 episodes in order. But if you feel like you need to jump straight to the question you/OP (BillingsKeith) raised, then the following episodes focus on powder selection, screening, and systematic load workup:
- Part 4: Powder Selection;
- Part 5: Use Optimal Powders;
- Part 12: Pick "The Best" Powder for Your Application;
- Parts 13 - 16: (load workup once powder is selected)
IMO (unless you handload at the same location as your 100yd or longer shooting range), you will save yourself quite a bit of time and components if you plan to workup your loads systematically with steps designed to eliminate inconsistent components, charge weights, and seating depths, rather than jumping straight loads that others say have shot well for them. (You can find at least one thread here on Rokslide where I did take somebody's suggested load, loaded up a batch, and had a winner--but that was only because I had previously shot all the components enough to have a logbook of data where I could check the recommendation, confirm I had already checked for excess pressure at the recommend levels, and could plug all the "recipe" variables into GRT and confirm it looked safe and likely to shoot at least okay.) I suggest planning for at least the following stages of assembling loads and then going to the range to shoot each set before moving on the the next stage:
- 1st Prep/Range Trip -- at least 10 shots per powder: Identify one and (only one) bullet you are going to hunt with, then identify the powders that best fit the parameters of your cartridge and barrel with that bullet, then load/shoot a pressure screening ladder for each of those powders with that bullet (See Parts 1, 4-6, and 12). During this test, do not vary any components or variables except the powder and powder-specific charge weights used for each group.
- 2nd Prep/Range Trip -- 30 shots: Using the results of that first range trip, examine each of the 10+shot groups you now have for each of the potential powders. Identify which of those potential powders was most consistent each powder's range of charge weights. Put aside all the other powders for now. Now load and shoot a round-robin OCW test at intervals of (in the 30-06) at least 0.2 grains and not more than 0.4 grains, shooting 3 shots per charge weight. Make sure your intervals span a range from your max charge to at least 2 grains below max. Shoot all three shots in each group even if the first two shots make "too large" a group--you're not yet trying to pick the smallest group size, but identify a series of charge weights where the average POI for each group stays close together for a sequence of at least 2, but hopefully 3 or 4 charge weights. At this stage, do not change any component or variable whatsoever from what you used the in Stage 1 (except for the weight of powder used in each group/interval; everything else should be the same as what you used in Stage 1). (See Parts 12-13.)
- Third Prep/Range Trip - First Option / 30 shots: Use the results of that second range trip to identify a charge weight in where the groups on either side of it have the same (or closest) average POI. If the groups around and near that charge weight are not as small as you are looking for, then you can use your selected charge weight to load and shoot a 30-shot/10-interval seating depth test. At this stage, do not change any components or variables at all (except for the seating depth used for each group/interval; everything else should be the same as what you used in Stage 2). (See Parts 14-15.)
- Third or Fourth Prep/Range Trip -- 20 shots: If the groups near that charge weight are already as small as you are looking for (or you have finished the seating depth test), then are ready to load at least 20 rounds at your chose charge weight and seating depot, then shoot a 20+ shot group (or if the bullets are stacking on top of each other, shoot 2 groups of 10 shots or 4 groups of 5 shots, then aggregate all 10 shots as one composite group). That will let you know if your recipe is going to be good enough even when you account for "outliers", and you can use that composite group to zero your scope. At this stage, do not change any components or variables at all--every cartridge should have the same components, same specs, the one charge weight identified in Stage 2, and the one seating depth identified in Stage 4) (See Parts 15-16.)
If there are multiple powders you think are good candidates shoot a 10+ shot pressure screen for each of those powders at Stage 1. If you only screen one powder at State 1, then do Stages 2-4 to develop that powder, you will be expending 50 to 80 shots to develop that one powder without knowing if that powder *on target* is the most promising and easy to work up. Then you have to go back and shoot another 60-90 shots to work up another powder and find out if it is a better option. Shoot the extra 10 to 40 shots at Stage 1 so you know that, during Stages 2-4, you are working with best powder for that bullet in your rifle. If you try and avoid an extra 10 or 30 shots at Stage 1, you are likely to waste 50-80 shots and LOT of time using an inferior powder in Stages 2-4. (The same principal applies to doing the entire systematic test at each of Stages 2-4.) So you definitely need at least 100 of your chosen bullet before you start; 150 would be better. (If you clean your barrel between range sessions, then you also need to add 3-5 fouling shots at the beginning of each stage (so an additional 9-20 bullets).
Some high-performance cartridges (such as 7 PRC, 22 Creedmoor, maybe 22-250, many Weatherbys, etc.) may have a barrel life of only 1200 or even 750 shots, so it may be important to streamline so that load development can be accomplished in 60 or 75 shots. But a 30-06 has ample barrel life for a systematic approach that will save you headaches, repeated stages, and second-guessing afterward.
Have fun and enjoy the loading and shooting!
