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baker
02-17-2017, 12:06 PM
I have been shooting my Glock PDW suppressed at 100 yards for fun, and I noticed that HST 147 +p's are very flat shooting.

I zero at 15 yards, and the point of impact is about the same at 100y. Not sure why, but I'll take it. Really surprises me with this heavier round.

CaptBeach
02-17-2017, 12:38 PM
Have not looked at a ballistics chart for 9mm 147 but I suspect your seeing it cross the plane in its arc, at 15 and 100. It will drop like a stone thereafter.

DeltaCadet84
02-17-2017, 02:58 PM
Try it at 50, you should be hitting high by an inch or more (I think)

baker
02-17-2017, 03:24 PM
Try it at 50, you should be hitting high by an inch or more (I think)


Will do. I shot it at 50, but I don't remember where exactly it was hitting. Standard pressure Rem GS 147 gr shoots 4-5" low at 100, which is why I was surprised at this one

DeltaCadet84
02-17-2017, 03:25 PM
Will do. I shot it at 50, but I don't remember where exactly it was hitting. Standard pressure Rem GS 147 gr shoots 4-5" low at 100, which is why I was surprised at this one
That is interesting. I guess there is one way to find out 👍

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Scottman
02-17-2017, 03:55 PM
very nice!

ON THE other end of 9mm not subsonice the 9x25 dillon in the 9 inch barrels shoots pretty flat to 200 yards

Yondering
02-17-2017, 04:08 PM
Will do. I shot it at 50, but I don't remember where exactly it was hitting. Standard pressure Rem GS 147 gr shoots 4-5" low at 100, which is why I was surprised at this one

The difference is more likely a change in POI that you're not noticing at your near zero. Can you detect a 3/4" difference in POI at 15 yards? That's about the width of your trigger finger. Many shooters can't, and that 3/4" is enough to change it 5" @ 100 yards.

This is a classic example of why the far zero is much more important than the near zero (although more so with rifles and longer distances).

"Flat shooting" comes from higher velocity. You won't find that one subsonic 9mm load shoots magically flatter than another, but will find that point of impact varies.

DeltaCadet84
02-17-2017, 04:28 PM
https://youtu.be/tF_zv3TCT1U

^^ Mythbuster video showing which lands first, a bullet fired flat or a bullet dropped.

The amount of bullet drop is a function of velocity. The bullet isn't "dropping faster", it is slowing down faster.

baker
02-17-2017, 04:53 PM
The difference is more likely a change in POI that you're not noticing at your near zero. Can you detect a 3/4" difference in POI at 15 yards? That's about the width of your trigger finger. Many shooters can't, and that 3/4" is enough to change it 5" @ 100 yards.

This is a classic example of why the far zero is much more important than the near zero (although more so with rifles and longer distances).

"Flat shooting" comes from higher velocity. You won't find that one subsonic 9mm load shoots magically flatter than another, but will find that point of impact varies.

Well, I was shooting into the top half of a 1" box at 15, so it was probably less than 1/2" high.

Paper Shredder
02-17-2017, 05:30 PM
The difference is more likely a change in POI that you're not noticing at your near zero. Can you detect a 3/4" difference in POI at 15 yards? That's about the width of your trigger finger. Many shooters can't, and that 3/4" is enough to change it 5" @ 100 yards.

This is a classic example of why the far zero is much more important than the near zero (although more so with rifles and longer distances).

"Flat shooting" comes from higher velocity. You won't find that one subsonic 9mm load shoots magically flatter than another, but will find that point of impact varies.

I was going to respond with similar points that Yonderling posted only with more layman words and less technical gibberish.

Yeah the 15/100 is probably a natural point of zero as per your bore axis / optics etc.

Yondering
02-17-2017, 07:23 PM
What "technical gibberish"? If terms like POI, velocity, and zero seem like gibberish, that's pretty sad.

Jon Payne
02-17-2017, 07:30 PM
Play nice gentleman.


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Paper Shredder
02-18-2017, 11:52 AM
Yonderling,

I was bowing to you. I started to type a response to OP, then I scrolled down to see it addressed better than I could. Don't take it any other way than that... there's no question you're an expert. Words sometimes do not exude the tone of self deprication like a live conversation would.

Yondering
02-18-2017, 05:08 PM
I'm not concerned whether anyone thinks I'm an expert at anything, that's not why I'm here. However, when someone says what you've just posted is gibberish, that's not generally intended or received in a positive manner.

I guess I misunderstood your intent. Carry on.