Take a scientific approach to reloading! Control variables and work up loads it the most organized, constant manner. Below is my process for working up a new load.
1
. Find max Jam. Take a sized, unprimed pieced of brass prepped exactly how you will for a loaded round and seat a bullet on the EMPTY case. Seat the bullet much longer than what will actually chamber in your rifle. Take this dummy round and place it in your rifle and close the bolt. This may take some firm pressure. What you are doing is forcing the bullet into the lands and pushing the bullet back into the case. Remove the dummy round and measure it from base to ogive if you have an OAL comparator, or base to meplat if you don’t have a comparator. Pull the bullet and re-do this step several times. You are trying to get a repeatable measurement on what your maximum cartridge length is.
2.
Optimum charge. Starting with a safe load, load 3-5 rounds of each charge working up in .3 grain increments per group. I usually do 8-10 loads in this charge weight work up. ALL of these loaded rounds should be seated to the same OAL as what you measured in the step above. You are only varying the charge weight. Go to the range and shoot all of these rounds at 100yds, each group at its own target/ aiming point. I use a bunch of 1” orange dots on the same piece of poster board. Watch for pressure signs on the case as you move up in charges, and stop if pressure gets hot (flat or pierced primers, ejector swipe on the brass, heavy bolt lift). Try to be ultra consistent in how you handle the gun. Again you are trying to limit variables. When you analyze this set of loads after you have shot them, you are not necessarily looking for the single best group. You are looking for 3 charges in a row that show the most consistent accuracy across all three, and the most consistent point of impact vs point of aim. You will probably see that as you work up in charge accuracy will progressively get better then worse then better, in a nodal pattern. One of these accuracy nodes will usually be significantly better than the rest. I usually re-test the three loads that I think cover the node shooting another 5 shots of each to make sure I have found a good node. I then select the middle charge of the three in the node.
Image one below shows the nodal pattern of optimum charge weight. Because 23.6 gr and 24.3 gr in the groups above were very good but 23.9 was not, I retested these three groups to see if I pulled a shot on the 23.9 group. In this retest, I found that all three shot 3 shot groups touching. So I will take the charge in the middle of the 3 charge weights and use that. This give a large window on either side of the selected charge.
3. Next I work on seating depth by loading every round with the charge weight selected in the previous step. The variable here is OAL. I start at the max length that was found in step one and used in step two, and I seat each group of 3-5 rounds .003” shorter than the last. So if my max OAL is 2.350, I would load 3-5 rounds at 2.350, 3-5 at 2.347, 3-5 at 2.344 etc. I usually cover .030 to .040 of total change in OAL. Shoot these rounds the same way you did the rounds in step 2 and analyze them the same way also. Looking for a node of 3 groups in a row of consistent accuracy.
Image two below shows the nodal pattern of optimum OAL.
4. Now you have optimal charge weight and optimal seating depth. From here I usually load 25-30 rounds of this load. I will shoot a 5 shot group or two at 100yds, a 5 shot group or two at 200yds, and a 10 shot group at 100 or 200dys, just to make sure that everything looks good. Then to make extra sure I've found a good load, I will shoot at longer ranges. I have yet to find a load in this manner that shot well at 100/200 yards but did not shoot well at long range.
After charge and OAL are worked out, you can test different primers, or change neck tension. But remember, one variable at a time, control all other variables that you can.
