Alex, I would recommend starting your foray into bullet pointing simply by sorting to OAL, or base to point as it has also been referred to here. Sort some bullets from a single Lot # into length groups of 1.5 to 2.0 thousandths. Practice setting and using your pointing die with as many bullets as it takes to get a feel for the process. I would suggest starting with bullets from the shortest or longest length groups first, as you're likely to get far fewer numbers at either extreme (outliers). That way, you can use the bulk of your sorted bullets, which generally fall into the middle length groups, loading for matches. I follow this practice loading for matches, that is, I want all the bullets for a single string of fire to have come out of the same length group. But I typically load the first 3-5 rounds with the length group outliers for use as my foulers before the first string of fire. I always have at least two sighters with the same length group as the rounds for record that I will use prior to shooting for score.
The idea of pointing is to close up the meplat significantly (although not completely), but not to close it up so much you create a "bulge" behind the point as the die pushes down on it. I usually point length-sorted (but untrimmed) bullets to where the meplat is closed up by about 50-70%, as compared to unpointed. This is enough to benefit from the process, but not so much as to overprint and create a bulge. When you believe you have the pointing die micrometer set appropriately for a given length group, record the micrometer setting. To point the remaining length groups, all you need to do is to adjust the micrometer setting by the length difference between groups. For example, let's say you sort into 7 length groups that differ by 1.5 thousandths. You practice pointing with the longest length group, then start to point the middle length group of the 7, which is Group 4. That is 3 groups away from #7, so you tighten down the pointing die micrometer by 3 x .0015", or 4.5 thousandths and start pointing. It makes it easy to set the pointing die consistently for different length groups within a single Lot# of bullets for every use.
There are a number of reasons why people use the particular methods they use for pointing. Each has its advantages and each has its caveats. No matter how you sort your bullets, the ballistic effect of length variance in some region of the bullet is going to be a potential concern, regardless of the pointing process you use. For example, bullets that are sorted only by OAL as I described above may differ in length in the bearing surface/boattail region such that they're all the same OAL, but might have slightly more or less bearing surface and base down in the neck when seated to a uniform seating depth. This could theoretically change the effective case volume and/or bearing surface-to-neck contact area. I don't view that as an issue because I can change seating depth for jumped bullets up to .009" in either direction without changing velocity enough that my chronograph can reliably measure it. Length-sorted and pointed bullets from within a single length group have nowhere near that much variance. The other question I would ask is, how much sorting do you really want to do? If you really wanted to, I'm sure you could sort by enough different parameters that you would get 100 different bullets groups from every box of 100 bullets. Obviously that is a ridiculously extreme example, but in general I prefer not to spend any more time sorting than I absolutely have to.
One purpose for trimming first is to obtain a more flat and uniform meplat prior to trimming. However, bullets of different length can end up with wider or narrower diameter meplats before they are actually pointed, depending on how much they are actually trimmed. This can also affect the pointing process. For that reason, I have never been fully satisfied with the points I generated starting with trimmed bullets. For the same reason, if you want to trim first, you really should sort by ogive after the bullets are pointed using a tool such as Bob Green's Comparator, but that is another sorting step.
The argument against pointing untrimmed bullets is that bullet meplats straight out of the box often have one side slightly higher than the other (i.e they're not perfectly "flat"). This unevenness is perceived to potentially caused imbalance. However, the closer in to the center axis of rotation the tip is closed, the less any unevenness actually affects balance as the bullet spins. In addition, the last few Lots of Bergers I have purchased have had much better meplats than in years past. They seem to have noticeably improved their QC.
The reason I'm going to this length here is simply to convince you to try the simplest and most expedient pointing approach first. That approach is simply to sort bullets by OAL and point them without trimming. If you do that, I can guarantee you will see a very slight improvement in elevation required at a given distance, but more importantly, a noticeable difference in consistency and group spread. If you wish to add meplat trimming and/or other sorting steps to the process at some time in the future, you can do so easily. I would also recommend that you determine at that time whether any of the added steps actually provide a measurable improvement before processing large numbers of bullets. If you can't shoot the difference, it really isn't worth the extra effort. Either way, starting out with the very simplest approach will help you get a good feel for the process without being too tricky. Further, it will only make it easier for you if you want to add more detailed steps at some point in the future.
