POI shifts at longer distance?

[earshot]

CZ scorpion evo3 is zeroed at 25m but has a significant shift to the left (out of the A-zone) at longer range (> 50m). My optic is an aimpoint pro.

Bulletweight doesn’t seem to matter. Gun holds 2-3 moa @ 100m.

Any ideas on what causes this drift of POI?

[HoMiE]

Parallax has the been the culprit for me at longer ranges with red dots. 

[Hi-Power Jack]

Sight it in at 50 yards, and see where it hits at 25 - just might solve your problem.     

 

How far does it hit to the left at 50 yards ?

[OdinIII]

Parallax has the been the culprit for me at longer ranges with red dots. 

This almost certainly the problem.

[chevrofreak]

I had this issue with my 9mm PDW that had a 1/9 twist shooting 147gr subsonic bullets.  I wondered if the bullets were being over spun and causing spin drift?

[earshot]

19 hours ago, Hi-Power Jack said:

Sight it in at 50 yards, and see where it hits at 25 - just might solve your problem.     

 

How far does it hit to the left at 50 yards ?

About 3-4 inches.

[earshot]

BTW: I asked Aimpoint the same question.

 

[Salsantini]

Borrow a different optic and see where the rifle shoots.  Maybe have someone else shoot the rifle to see if it also happens to them.

[AHI]

zero in at 50 yards then see were it hits at closer range as suggested above.

8 out of 10 times this fixes windage issues.

[Old3GNR]

I would suggest trigger control.  Do some dry fire and concentrate on any sight movement.

[earshot]

I’ve been shooting rifles for 35 years....I know about trigger control  so I would very much rule that one out. I will zero at 100m tomorrow and see what it will do at 20-25m next week.

[Chillywig]

If shooting inside 7 yards is your POI to the right? 

[earshot]

I zeroed on 100m last thursday.It took 5 clicks (aimpoint states 1 click is 16mm @100mm). Now I have to wait and see what the impact is (pun) on POI @ < 25m. I will know in a week or so.

Other than that: Roundcount with the Scorpion is at 6500 and only one malfunction, which was cartridge related.Mine has a shortened barrel and a magpul stock.Wear and tear are still the same as roundcount 1000.Being a lefty, the ergonomics are spot on.Accuracy is 2-3 moa if I do my part. The only negative is the lousy trigger....Oh, and check the tightness of the screws that hold the frame together as they tend to loosen up after 5000 rounds.

If I was righthanded I would probably opt for one of those nice JP’s but ergonomics are poor at best with those AR frames for a lefty.

Big thumbs up for CZ on this one! (Now go and improve those triggers)

[Ocrrhbow]

For a quick and cheap trigger improvement on the Scorpion buy and install an HBI reduced tension trigger spring for it.  This will provide you with a surprisingly large improvement in the trigger weight.  For a really first rate trigger job (but much more expensive) you could send your trigger group  to CZ custom.  I love my scorpion but am switching to a JP for the reduced recoil and dot movement.

 

[AHI]

Been over a week   report?  Other than real high where does it hit now?

Edited October 16, 2019 by AHI

[StealthyBlagga]

1) Parallax: The Aimpoint is designed to be parallax-free at 200 yards, so at 25-50 yards the dot needs to be centered as best you can. For this reason, my USPSA PCC wears a Trijicon MRO (designed to be parallax-free at only 50M).

2)Wind drift: 9mm bullets are surprisingly prone to wind. Any significant cross wind could be causing part of your issue.

3) Accuracy: Most 9mm PCCs shoot mediocre groups at 50 yards. If you are only shooting 3- or 5-shot groups, that variability alone may mislead you into thinking you have a problem. When I zero my PCC at 50 yards, I shoot 10-shot groups to dial it in exactly.

[Fasthenk65]

On 10/17/2019 at 10:34 PM, StealthyBlagga said:

1) Parallax: The Aimpoint is designed to be parallax-free at 200 yards, so at 25-50 yards the dot needs to be centered as best you can. For this reason, my USPSA PCC wears a Trijicon MRO (designed to be parallax-free at only 50M).

2)Wind drift: 9mm bullets are surprisingly prone to wind. Any significant cross wind could be causing part of your issue.

3) Accuracy: Most 9mm PCCs shoot mediocre groups at 50 yards. If you are only shooting 3- or 5-shot groups, that variability alone may mislead you into thinking you have a problem. When I zero my PCC at 50 yards, I shoot 10-shot groups to dial it in exactly.

Try to understand.... so for pcc a MRO is better then an aimpoint?

[StealthyBlagga]

17 hours ago, Fasthenk65 said:

Try to understand.... so for pcc a MRO is better then an aimpoint?

 

IMHO for USPSA handgun matches (max range 50 yards), the MRO is a better choice based on parallax and FOV. The difference is small, but may be noticeable at 50 yards under the right circumstances. I would not rush out to replace an Aimpoint I already had, but if buying a new optic I’d favor the MRO. 

[Fasthenk65]

5 hours ago, StealthyBlagga said:

 

IMHO for USPSA handgun matches (max range 50 yards), the MRO is a better choice based on parallax and FOV. The difference is small, but may be noticeable at 50 yards under the right circumstances. I would not rush out to replace an Aimpoint I already had, but if buying a new optic I’d favor the MRO. 

tnx

 

[earshot]

Update: after zeroing @ 100m (indoor) I finally had time to try it at shorter distances yesterday.From 25m it now shoots still ok with the ammo that you used for the 100m zero (4.5 N340, 125 HN HP). My practice load for PCC shot about 2-3cm to the right....not really a problem. So all is ok. Shot a 7cm 5-shot group @ 100m prone yesterday which I find pretty good for my shorttened s3.