zero question

sniperman

well folks,mate of mine went out today to check hi 243 zero,marlin,using 80 grain soft point,anyway to his amazement he found it was off by about 5 inches to the right,height was ok ,inch at 100 yrds,it was bang on about 15 shots ago,9 foxs could vouch to that,after missing a few he said ill check zero,and off it was,he is wondering as i am,how come it was off so much,bang on 15 or so shots ago,scope ,rings all tight,got no bangs or drops,a new hawke scope etc,so any ideas how it got off so much,?thanks

Vizzy

Assuming as you say that everything on the rifle is 100%, then there are probably only a few variables;

Different ammo from when it was last zeroed ?

Different batch of the same ammo ( unlikely to be that different, but you never know) ?

The wind today ( I was helping a lad zero a 6.5 today and wind was a factor)

The human element

sniperman

https://www.boards.ie/discussion/comment/118660045#Comment_118660045

hi,same ammo,same batch,as for wind was in a sand quarry so was not to bad,as for human error,he has and is a good shot,cant understand why it went off so much after a dozen or so shots,

Cass

Was the shot his first? Did he fire a few more shots to verify the results?

sniperman

https://www.boards.ie/discussion/comment/118660723#Comment_118660723

hi,ya he fired 3.all were off,so he re zeroed,he is within an inch now at 100 yrds,

Cass

If they all hit the same spot as the first shot (in other words grouped) then as was said above it was wind. A 35mph wind can blow a 243 rounds of by up to 4 inches, or more with gusts) at 100yds and it hasn't been the calmest of weeks.

Failing that someone intereferred with his scope, or he adjusted it but forgot.

Lastly he zeroed in poor conditions and with a change in conditions the zero, while fine for elevation, was not set for windage. Example being he zeroed on a windy day with a right to left wind. He dialed on an MOA or two for wind. Got his height, dialed in the wind and was hitting bulls. Now he shoots but the wind is left to right, blowing much straonger than when he zeroed, and his scope already has a couple of MOA in the direction the wind is blowing so it "amplifies" the windage discrepency.

If everything is checked and tight, and no damage to the rifle/scope then its a setting or environmental factors. Simple as. Not being short with you at all, but its one or the other, equipment (including human) or conditions.

Check again, at regular intervals, taking note of the wind speed and direction. If the elevation is not affected then its almost guaranteed to be enviornmental, but don't dismiss the human factor. Different eye relief, cheek weld, etc. will cause issues.

Its just odd that the rifle grouped. Had there been a problem with ammo or scope or rifle it should have been worse and/or random. All signs point to the above (conditions).

Cass

Meant to add last night that if you try the rifle again, when the weather conditions settle, I'd be pretty sure the zero will be off again as it was zeroed in the conditions from the day your friend done it.

Always bets to zero a rifle in as calm/perfect conditions as possible.

sniperman

thanks all for help.ill tell him to check zero again on a calm day,ill be there as well

gapjnr

By any chance did he clean the barrell between tines of going off zero. I've a tkkka t3x and notice after cleaning it might be slightly off zero for a few rounds but not to the extent of the 4"..

JP22

All things being equal and if rifle/scope/ammo/user were good, then it’s probably down to wind. It can be very calm at shooter position but blowing a gale at 100/150 etc. Even in a quarry, strong winds can be worse when blowing over the sides/banks.

Most users forget the turret markings when zeroed and likewise if someone else (little fingers perhaps) moved the turret most wouldn’t notice.

If your scope had adjustable turrets, once you are zeroed, unlock and reset them to zero. Now if you adjust later on or someone else moves them it’s easy to see, you just dial back to zero mark and you’ll be on or damn close.

Cass

While the weather has not been great did your friend get a chance to recheck zero?

sniperman

https://www.boards.ie/discussion/comment/118677701#Comment_118677701

hi,yes he has is set now again,hitting an inch high at 100 yrds,will be going after deer the weekend,thanks to all for the help

Paddyviking

Hi

What scope mounts are you using

I had similar issues and it turned out to be the mounts

Got myself a set of Teir One mounts and haven't looked backed

Pv

sniperman

https://www.boards.ie/discussion/comment/118695834#Comment_118695834

hi he is using a set of hawke mounts,they seem ok,

Cass

Any update, progress or continued problems?

sniperman

https://www.boards.ie/discussion/comment/118770492#Comment_118770492

hi no more issues to date,he is putting down the problem to maybe an unnoticed bang off something,cant figure out anything else,he got 5 foxs in 2 nights,so he is happy,thanks to you all for reply's