New Ammo New Zero?

[RiskyBusiness]

I dont know much as i've only just started shooting and currently trying various brands of 223/556. I've seen YT vids of gun owners taking all kinds of boxes of ammo with variances in grain, manufacturer, etc. With all different outcomes, my question is if you zero your gun with a specific gr and caliber lets say 55gr 223 from brand x, if i were to now use brand y 556 55gr will there be a significant difference in groups/accuracy that would need warrant a new zero?

have any of you noticed certain ammo favors another area of the target where you normally dont see your groups land?

[baih777]

Yes

[kcheung2]

Different zero? Yes. Significantly different? Too many variables and subjective terms to answer.

[jeremyro]

The real answer is it depends on how good you need your zero to be. I alternate between different 55gr and 62 grain loads with about 2moa shift max. That being said sometimes you get a real outside ammo type that needs a real re-zero.

I was working on loads for my 338 lapua recently and the 250 gr and 300 grain loads were landing perfectly in the same group. You never know.

[RiskyBusiness]

Different zero? Yes. Significantly different? Too many variables and subjective terms to answer.

thanks its good enough, i'll just stick to the ammo i have most of to practice with then when i can be more consistent ill try out the other brands i have where i can record the results.

[steelheadmike]

For cheap, 2MOAllDayLong ammo? No (significant) difference. For precision shooting, maybe/yes.

[Donk310]

Usually yes. But I've in the past used .223 and 5.56 (both 55 grn) interchangeably and they have been dead on. The only way to truly find out is to go bust a few rounds and see where they hit.

[MudCamper]

Yes. What I do is zero with my favorite ammo. Then when I shoot something else for the first time (and in the same rifle), I start the day with some careful shots on paper. Then I note the average difference of the groups of new ammo. Then I write down the hold over/under/left/right difference I need for that ammo. I keep a growing list. Sometimes it works...

[navyrifleshooter]

Yes, there can even be differences between lots of the same manufacture....i.e. Brand X 55 gr 5.56 lot number 123456 can be different then Brand X 55 gr 5.56 lot number 234567.

Only way to be sure is go and shoot some.

[Mitch]

With centerfire rifles the answer is "Maybe."

With rimfire, the answer is "Yes."

[thegamettt]

for plinker ammo no, but if you have a precision rig, maybe. I usually find what it likes the best and use only that. That's just my case though.

[Rhyyke]

I always check the zero when I start a rifle session, and usually some small adjustments need to be made. Usually it's back on point after 1 mag or so.

[GM4spd]

Usually yes. But I've in the past used .223 and 5.56 (both 55 grn) interchangeably and they have been dead on. The only way to truly find out is to go bust a few rounds and see where they hit.

Can you specify the distance you were shooting at---that both 55 grain bullets
in 556 and 223 were dead on? Not to doubt,just wondering.

[Maximus924]

not only different ammo, but different quantities of powder in a hand load can change the point of impact as well

[glockman19]

YES, unless you are handloading stick with the ammo that shoots best out of your firearm. If you change ammo it is likely your zero will move and require adjustment.