Different places with Different Ammo??

[miles71]

Why does different ammo shoot differently? I have found I can get good groups with different brands but often times the groups are in different places on the target by brand.

Whattsa up wiff dat??

TD

 

[Erich]

You know, you slightly change the friction in the bore from one round to another (due to slight differences in the hardness or diameter of different bullets) and you slightly change the velocity through different powders and bullet weights used and different crimps applied, then you slightly change the way different bullets fly due to their slight differences in profile and sectional density . . . and you get different results.

The answer to your question is that different loadings are different in many different ways, and those differences lead to different results between them.

 

[Dragon88]

Every load is different, whether it's loaded by you or the factory. When you find one that your pistol likes, it may be that the bullet is a little different, or the brass is sized differently, or the velocity and pressure curve is different, the list goes on of possibilities.

Generally, lighter bullets will hit lower on target compared to heavier bullets in pistols. This is due to the recoil and an effect called barrel dwell time. As for lateral drift, this one is hard to pin down. I don't see it much in pistols but occasionally a load will tend to print slightly left or right. It's seen more in rifles, because when a bullet goes down a long rifle barrel, the barrel whips. This is called barrel harmonics, not unlike the harmonics of a musical instrument. One load may release the bullet in "mid whip", while another will release the bullet at the top or bottom of a whip. Thus you will get a slight change in point of impact.

 

[PDL]

well if you're talking about factory ammo, every gun has it's likes and dislikes as it were. Factory ammo is one size fits all. Your gun might not be part of all for a particular round.
That's why you need to get into reloading. Then you have some control over what's happening.
So, if you can't reload find the factory stuff your gun likes, and stick with it.
They have different bullet, powder, brass components no reason to think they'd all perform the same.

 

[moxie]

I've found the Midway stainless "Mid-Whip Gauge" an essential resource in resolving differences in different ammunition in different firearms. The digital model in particular allows the shooter to factor in differences in temperature, pressure, and FO2 of ambient air, thus producing a difference prime absolutely essential for choosing that perfect round for that particular gun. Check it out.