The question constantly comes up about truing your dope to your ballistic software. The problem is, people go out to the range with software in hand and then can't quite understand why it is not matching up or they have troubling "truing" it after the fact. Not all, some find it pretty easy, but the forum is full of people commenting about the ballistic software errors.
There are several reasons why software may not line up properly, but part of the problem is using the software first and not doping the rifle prior to exploring the ballistic solvers. When using software prior to shooting I call anything the computer spits out as "Try Dope", because you are just trying to hit the target, not much more. It's not 1 MOA accurate. Remember manufacturers drop data was designed to get you on an NRA 6x6 target board, it was up to the shooter to fine tune that drop to hit the center. We never questioned it, we just knew we needed to put in the effort.
My personal argument has always centered around the human factor. That regardless of what Doppler says, what the computer model says, the human factor has a much bigger say as to where the shot actually hits. I have heard several times that what they saw in a fixture was not what happened when they put a shooter behind the rifle. It comes down to recoil management. This is why one shooter will hit using Solution A an the next shooter needs Solution B or C. How they manage the recoil and exactly where that barrel is upon release of the bullet. It's why your zero and your friend's zero are inches apart. No software out there considers you, it only considers an empty, near perfect world.
The next problem is the promotion of "drifts", we have a lot of new data that points to a series of drifts that can effect the placement of the shot. The promotion of these is a relatively new phenomenon. When I went to Sniper School back in 1986 we didn't worry about Spin Drift, (wasn't even mentioned) we didn't worry about Coriolis, Cross Wind Jump, or any of the other examples we see today. Baron Roland von Eötvös, who the heck is that guy ? In all we have about 4 Drift factors that are discussed and some people start employing a correction for them as close as 400 yards. Am I saying they don't exist, no, but I am saying they are being blown out of proportion. I think much of it is used to take the blame away from the shooter. Here is why:
If we gather our dope by walking our shots out, actually shooting each yard line distance and recording the data we include everything. Including the drifts. There is really no such thing as a No Wind day, if you experience one consider yourself lucky, but practically speaking, no wind doesn't exist. So under normal circumstances, we zero and dope our rifles with everything already included. Then when we go to our "Data on Previous Engagement" it's taking into account these factors. If today I am shooting to 1000 yards and used 7.4 Mils to hit center along with .75 Mils of wind for 5 MPH breeze, that assumes all the drifts and drop data. If conditions change because of the location or atmosphere, a computer will help account for it rather than the old, outdated rules of thumb, but still, hitting the target usually happens. We see this every week in tactical rifle matches around the country. Guys travel from their home location to ranges 500 miles away and hit. Why do they hit, they practiced and recorded their dope. Talking to several high scoring PRS Shooters, they strive to nail down their data so elevation is a given and the only question becomes wind. In known distance courses they consider this information their zero data. They essentially re-zero the rifle for each yard line.
Wind is the biggest drift factor we have and actually will offset some of the other drifts. It depends on the direction, and speed, but it will cancel out or increase several of the other factors. So it's important it to understand the wind. No dispute, you need to know what is going here as it can control so much of how we hit the target. That includes elevation changes. To expand, it's not unheard of to have a terrain feature in or around a specific yard line that causes an elevation issue, so even if everything with the computer lines up, your 700 yard dope is off because the wind changed the flight path to hit that one target. It often has people scratching their heads. Every yard line is on target with your software by that 700 yard line. Odds are it's wind, though it could be an error in your scope if you never calibrated it.
Still, if we recorded our data, we know what the wind was doing, so if we doped the rifle in a 5 MPH wind, going to an 8 MPH is not like starting from zero. So while they might say an 8 MPH wind will move the impact .1 Mils up or down, it's really only 3 MPH we are dealing with. We already accounted for 5 MPH so why add 8 MPH on top of the 5 ?
If you're modeling the shot on a computer, I can see the importance of all this. But it's not the same as shooting it. Not to mention we miss out of adding our own spin to the bullet. Poor fundamentals will NOT line you up with the model. If you are adding .2 Mils of trigger hook to your shot and you want to call it Spin Drift, well okay, I suppose you can, but are we really talking about the same thing. Why did I not use any, and you are using .2 ? Why is my wind call 1.5 Mils to hit the target and you are using 2 Mils to hit the same target ? Happens every week. Maybe it's rifle cant ?
The point is, while all these effects exist, they are not equally distributed among the shooters. We all release the shot in our own way. So before you go adding all the drifts to your ballistic solver, try doping your rifle first without any software. Develop YOUR dope to distance and record everything, then True the software to what you shot rather than worry about what the computer said before your first round went downrange. It only takes an hour, and I did for this video in 50 shots. Now I can go back and line the computer up at my leisure. I think you will find the variations are much smaller than you realize. Solid Dope is hard to argue with as we all know the bullet has the last word.
The process we used was,
1. Mounting the scope. I used a Level Rifle - Level Scope set up, with a deck of cards to line up the flat of the scope to the rail of the rifle.
2. I checked level on the range in position with a 4ft Level at the target. Ran a shot-less tall target test with the level.
3. Zeroed the Rifle at 100 yards and reset my turrets.
4. Gathered dope on steel from 200 to 1000 yards recording both Wind & Elevation used. I wanted POA to equal my POI.
5. I Chronographed 47 shots throughout the process using the Labradar.
6. Upon return I began working with my ballistic software to match my recorded drops.
There is no disputing what is being said, there is disputing how much it actually effects us on the range. All I am saying is, "it's already in there" especially if you dope it first.