I was at the range shooting some S&B 9MM 115 gr ball ammo. The rounds were hitting my target a little low. Sights were fine, no issues with them. Afterwards I was talking with the Range Master and he said that 115gr fly lower than 124gr and 147gr. The guy is a longtime shooter and seems to know his stuff. Is this accurate info...He felt using 124gr the round would hit closer to a 6 o'clock hold where the 115gr hits like lower.
Do Different 9MM gr weights fly differently?
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Hell no. You are shooting a pistol you can't expect at gun fight distances 1 MOA. If you are shooting low from what I read you have a trigger control problem. You are either snatching the trigger or gripping the weapon just before you fire that is causing you to shoot low. 115,124,147gr does not have anything to do with that and it is also not the weapon. You are either sighting wrong or pulling the trigger incorrectly.
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The heavier bullets travel slower down the barrel; thus exiting the barrel later in the recoil cycle (higher); thus causing the bullet to strike the target higher. Remember it doesn't take much of a difference for a decent change in point of impact.
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Different bullet weights of any given cartridge will fly differently. For a more dramatic example shoot 150's then 180's from a 30-06 at 500 yards.
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Yes differing bullet weights in the same caliber through a particular gun will hit to different POA/POI. Even with all the CNC machining two Glock 19's for example might hit to completely different points with the same round. I'm curious. Whn you shoot ar you covering the area you want to hit with the front dot of the sight or a 6 o'clock hold? Most European guns are set up to covr th area you want to hit with the front sight. Not below as in a 6 o'clock hold that many target pistols have. Just FYI.
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Wrong. Even though this may be a variable, bullet weight most definitely does affect POI....
Correct Answer.
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Absolutely incorrect!! The POA/POI will vary with different bullet weights. Variations are also observable by changing powders, powder charge, OAL and even (though only to a lesser extent) crimp.
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At close range the difference is insignificient. If you see significient changes on the handgun target range its most likely secondary to firing method.:wavey:
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The range master needs more shooting time, just not true. You can have diff POI w/ identical bullet wts from diff manuf. It just depends the powder & bullet & your gun. There are few hard & fast rules when it comes to ammo, bullet wts & POI. What distance are we talking about & how much is " a little low"?
This is the barrel time theory, which I don't agree w/. Shoot a 115gr bullet @ 900fps & a 147gr @ 900fps, identical vel & bbl time, the heavier bullet almost always shoots higher. It's even more pronunced when shooting larger caliber rounds like 44 & 45.:dunno:
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I must respectfully disagree. It is not uncommon to see a 2" difference in POI on targets as close as 7yds when comparing 115gr vs 147gr bullets.
If all you are trying to do is shoot a full-sized target anywhere on the cardboard at 7 to 10 yds, this difference may be negligible but, if you are trying to accomplish a challenging shot such as an upper "A" zone hit on a USPSA at 35 yards, you better know your pistol's POI in reference to your POA. A variation of several inches on a 35 yd target is HUGE and, when making tight shots, said difference may cost you valuable points.
I do want to reiterate what I mentioned before: the bullet weight is not the only variable that affect the bullet's trajectory. We must also consider all the other variables of the reloading components (powder, powder charge, OAL, etc). Granted that the shooter's input will have a measurable effect due to their handling technique. Nonetheless, bullet weight alone, will affect how the bullet prints on paper.
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