Re: A Testing Process By Matthew Cameron
Finally, something in writing which outlines the process of load development! Thank you.
I have been working on my own process, and like was suggested, it is my own OPINION, so here it is:
First is the selection of components based on research, as has been suggested.
I also shoot 3-shot groups, but shoot 3 groups of 3 shots for each load. I find sometimes considerable variation in group size for a given load. I load 10 rounds for the same load. I shoot the 1st round as a "fouler", and then procede with 3 groups of 3 shots. I will then clean between each different load.
I increase my charge weight by 0.5gr each time. I inspect each case after firing to look for pressure signs. If these start to show before I reach the book max, then I stop. If not, then I procede WITH CAUTION. Some of my loads are quite a bit above book max, but still show no pressure signs for my rifle. I will usually load up 50 rounds at this initial stage, allowing for 5 different loads.
Next, I select the most accurate load (average group size from the 3 groups of 3 shots) and play with bullet seating depth. I usually start about 20 thou off the lands and load 5 rounds for each seating depth. I shoot these as a single 5-shot group. I guess you could argue that I'm not consistent in my practice here, but I don't think this will have as much variation as the powder loads will--again, just purely speculation here not based on any science or fact.
Once I've selected the most accurate seating depth, I then try to fine-tune my load. Again 3 groups of 3 shots, but this time loads are increased by 0.2gr. Again I load up 5 different loads (50 rounds) with the middle middle load the same as the most accurate load from the first test. These are now all seated to the most accurate seating depth as well.
I then select the most accurate load of this test and further refine the load to 0.1gr, now shooting 3 5-shot groups. This means loading up 15 rounds for each load. The middle load is centered on my most accurate load from the above test, going 0.1gr to each side. I then select the most accurate of these loads as my final load.
Some may feel this is too much shooting. This is something I've been wrestling with. It does use up a large chunk of useful barrel life, especially in some of the calibers that are "Barrel Burners". I don't have a good answer to this, but again, I've seen large variations in group size between the three groups of 3 shots. If I had gone with the one group that was 0,110" for one group as my most accurate load based on one group, I'd have missed the other group that was 0.710" that was shot 2 groups later (same loading). I think you get more accurate data this way--again, just my opinion based on my experience.
The other thing some may have noticed is that I have tried to keep the number of rounds I load up for a given charge, to multiples of 5. There is no other reason for this than convenience, as my ammo boxes are 50-round boxes. It just makes labeling easier to have the whole row of 5 rounds the same charge weight.
Last edited by johngfoster; 08-28-2008 at 12:17 PM.