Beginner issue with sight adjustment

[ummm]

Indoor range, got my pistol sighted in at 25 yards. In case I'm using incorrect terminology, by "sighted in" I mean I would shoot 5, approximate the center of that group, and make changes to my rear sight to bring that center to my POA. Lather, rinse, repeat. Got it to where I was shooting the best groups of my young career at 25 yards (for you guys it would probably be terrible groupings).

Then I shot at 10 yards, all my shots were pretty darn precisely 1.5" low (I was shooting at the 3x5 card part of a FAST target, and all 5 shots were inside the black outline of the 3x5 box...my POA was dead center of that 3x5 box :( )

So I'm stumped -- if I adjust my sights for the 10-yard, I'll screw up my 25-yard happiness, won't I?

Is it possible to have a rough (say, +/- 1") POA=POI for all targets in the, e.g., 10-25 yard range, or must significant adjustments in POA be made?

I've read that some guns shoot more "flat" than others, perhaps I just have a very non-flat shooting gun? It just seems like the ballistic path wouldn't be that markedly different over a mere 15 yard difference, but I'm a total n00b, so my perception is probably quite wrong.

It's a 9mm shooting 124 grain fmj, if that matters.

Thanks in advance for any hints

[JV_]

For many of my guns, I use a drive-the-dot sight picture at ranges <= 10Y, this means I'm putting the dot over where I want the hole (holding-high). I use a center hold at distances >= 15Y.

I don't consider a 1.5" POA/POI difference between 10Y and 25Y to be abnormal.

[ummm]

Thanks, JV -- if it's not abnormal to you, then I'm in good company.

[orionz06]

I have used Warren sets, Ameriglo sets, 10-8 sets, and a few others and almost all of them in a properly functioning pistol are shoot the dot to around 10y with the same average variance, save for drastic ammo differences.

[ummm]

I have used Warren sets, Ameriglo sets, 10-8 sets, and a few others and almost all of them in a properly functioning pistol are shoot the dot to around 10y with the same average variance, save for drastic ammo differences.

Thanks, orionz06. I guess a large part of my reaction is (perhaps incorrectly) reading ballistic tables, which have led me to expect a far flatter trajectory. The two or three I looked at all agree with each other, so maybe it's my inability to use them correctly, but for example, here's one that was generated for the 124 gr Speer Lawman I've been using:

http://www.shooterscalculator.com/images/trajectory/ballistic_trajectory_chart_151a8703.png

full info at:
http://www.shooterscalculator.com/ballistic-trajectory-chart.php?t=151a8703

It seems to tell me I should be very close (+/- half inch maybe?) out to 25+ yards, but that's just not been remotely close to my experience (and apparently JV's, as well).

The sight height I took from the Dawson Precision website (so I'm guessing it's pretty...precise!) and the Speer website gave me the data for the cartridge, so that should be spot on as well.

Are these ballistics charts wildly inaccurate? If so, can you point me to an accurate one, because I'd love to understand more about the ballistics of the cartridge I'm using -- I think it will help my development as a shooter.