Zero Shift? Tikka/SWFA/UM Rings

[mxgsfmdpx]

As a follow up: I overlaid groups 2-6 (post adjustment) onto a single sheet once I got home. Right at 2 3/16" for 28 shots.

Not as pretty as some peoples groups, but for myself shooting <1k rounds per year I think this is probably reasonable and reflects my level of competency more than a failure of the rifle system?

Open to other thoughts though if anyone still suspects an equipment issue?

I'll do another zero check before my next hunt and then I am switching to factory ammo as I'm not setup to reload at the new house yet. Will shoot a 20 rd group building the position each time prone across my backpack, then do a few drops to check everything again too.

Sorry if I missed it. What was the shooting position for these overlaid groups? All shot at 100 yards and from the same position?

 

[TX_Diver]

Sorry if I missed it. What was the shooting position for these overlaid groups? All shot at 100 yards and from the same position?

Prone over my pack with bino harness rear support. The first few posts shows the individual groups and if I rebuilt the position or not

 

[eamyrick]

We call this sniper rifle voodoo for a reason. I’m pretty ocd and have seen what you are dealing with enough to get burnt out on long range shooting. How the sun hits the target, how the sun hits your objective, how tight your shoulder is from doing a heavy workout, plate carrier strap pushing the buttstock, etc.

 

[Formidilosus]

Prone over my pack with bino harness rear support. The first few posts shows the individual groups and if I rebuilt the position or not

This is almost certainly the issue. Very few shooters could do 2 MOA from a pack for 30 rounds.

Start at the start- use a stable rest front and back. A cinder block, real front rest, and real rear bag is cheap and easy to setup, and will show what the gun is doing baseline. Without that, you have no idea if it is you or the rifle.

 

[mxgsfmdpx]

Prone over my pack with bino harness rear support. The first few posts shows the individual groups and if I rebuilt the position or not

Well then that’s better shooting than most despite what the internet will tell you. Everyone on the internet shoots “sub moa all day” even though they don’t ever actually shoot much in real life, let alone from anything other than a bench at a “gun range”. If you really want to chase gnats ass you need a better “position” for the true 100 yard zero.

Zero shifts can still happen even with proven setups like yours. There are no “guarantees” we are simply eliminating as many variables as possible per the Form method as you’ve done.

I finally had an impact shift on one of my .243 Tikkas using UM mounts and scope was SWFA fixed 6. There was no “known” hard drop or knock or anything out of the ordinary. Just used in the field for several thousand rounds and bouncing around in vehicles.

I adjusted the 100 yard zero and the shift has not happened since. I beat on the stock, beat on the scope, it’s been back in the same shooting/riding conditions since and still no shift in over 6 months.

This one was installed with blue loctite instead of paint pen, so maybe that’s the culprit but, again, it hasn’t shifted again since so if it does I’ll pull it apart and see how the loctite held up.

 

[TX_Diver]

This is almost certainly the issue. Very few shooters could do 2 MOA from a pack for 30 rounds.

Start at the start- use a stable rest front and back. A cinder block, real front rest, and real rear bag is cheap and easy to setup, and will show what the gun is doing baseline. Without that, you have no idea if it is you or the rifle.

10-4.

So that’s kind of my question I guess. I can probably shoot a “better group” by staying prone and shooting from a bipod or cinder block with a pint size game changer lite up front and a rear bag, and minimizing how many times I build the position. But if I’m not using that stuff in the field am I not better off getting a zero based on how I’m going to shoot, even if it’s a bit bigger group?

Or do I need (or should I want) that baseline rifle info even if it’s not how I’m shooting in the field?

 

[HighUintas]

10-4.

So that’s kind of my question I guess. I can probably shoot a “better group” by staying prone and shooting from a bipod or cinder block with a pint size game changer lite up front and a rear bag, and minimizing how many times I build the position. But if I’m not using that stuff in the field am I not better off getting a zero based on how I’m going to shoot, even if it’s a bit bigger group?

Or do I need (or should I want) that baseline rifle info even if it’s not how I’m shooting in the field?

I think for determining what load is the best or for identifying a weak link, I would go with sandbags for rest to eliminate variables and figure that out with as few rounds as possible.

But for determining zero for field shooting purposes, I would do it off of what u use in the field and build position every time.

Going even further, maybe find zero by including multiple field positions if you find poi is a bit different for say sitting using sticks vs prone. I haven't done this, but I do find field zero using my pack and rebuilding position. It works well.

 

[Marbles]

I established my zero off a pack with a rear bag (I carry the bag in the field).

The only value I see in shooting from a more stable rest is if you are questioning the rifles capability.

I'm just another nut behind the trigger though, so take what I do with a grain of salt.

 

[Formidilosus]

But if I’m not using that stuff in the field am I not better off getting a zero based on how I’m going to shoot, even if it’s a bit bigger group?

No. The zero is the zero. Zero from the most stable and consistent rest possible, then practice from the pack. Hiding an error by zeroing of the pack if you have a POI shift between the pack and rest, is just stacking errors on errors.

Or do I need (or should I want) that baseline rifle info even if it’s not how I’m shooting in the field?

Yes you want it. If there is a difference in your POI from rest to pack, you need to know that and figure out how to eliminate it. Rifles should not be having a shifting zero between positions.

 

[mxgsfmdpx]

I established my zero off a pack with a rear bag (I carry the bag in the field).

The only value I see in shooting from a more stable rest is if you are questioning the rifles capability.

I'm just another nut behind the trigger though, so take what I do with a grain of salt.

For "checking" a known zero in the field before a hunt this is acceptable. You shouldn't then be correcting out MINOR deviations to a known good 100 yard zero though.

For establishing the baseline/known/solidified 100 yard zero, shooting off of your pack with a rear bag is not ideal.

 

[Marbles]

Yes you want it. If there is a difference in your POI from rest to pack, you need to know that and figure out how to eliminate it. Rifles should not be having a shifting zero between positions.

Other than barrel channel pressure issues, I have always considered a POI change between positions to be shooter error and an indicator of a shooter problem that needs to be fixed. Is that a correct view?

 

[Formidilosus]

Other than barrel channel pressure issues, I have always considered a POA change between positions to be shooter error and an indicator of a shooter problem that needs to be fixed. Is that a correct view?

Yes sir. But, that’s why you don’t zero off of a pack. Zero off of the most stable, most shooter eliminating rest/position possible, then check zero from the pack.

 

[TX_Diver]

Yes sir. But, that’s why you don’t zero off of a pack. Zero off of the most stable, most shooter eliminating rest/position possible, then check zero from the pack.

10-4. This is a significant improvement over my 3-5 round zeros of a few years ago (with a scope from a brand that was beloved to the local Wisconsin community lol)

Would you do 20 rds from each? Or 30 from the stable position then 10 build/break off a pack? Or just burn 60 and do 30 from each position?

Would you build/break position each time for the more stable position or just for the shooting from a pack to see if there is a difference?

 

[HighUintas]

Good God apparently I suck and I've been doing it wrong for the last few years

 

[Formidilosus]

10-4. This is a significant improvement over my 3-5 round zeros of a few years ago (with a scope from a brand that was beloved to the local Wisconsin community lol)

Would you do 20 rds from each? Or 30 from the stable position then 10 build/break off a pack? Or just burn 60 and do 30 from each position?

Would you build/break position each time for the more stable position or just for the shooting from a pack to see if there is a difference?

1). Lay down in the stable rest and shoot 3x ten round groups. Let the barrel cool between groups (for barrel mirage reasons). Zero off of that.

2). Take the cone of the 30 shot groups and use that as the target. Then, break and build the position practicing until you are keeping all shots inside the cone- think bullseye shooting. You could use a NRA B8 bull, but legitimately the S2H target was made for this. You’re looking for a 100pt-10x score for ten rounds if using a B8, and everything inside the 2 MOA circle with the S2H target.

3). Do the exact same above, start standing then go to prone and make it 30 seconds for 5 rounds per string- do this twice for a 10 round group. Again, once you are consistently doing 10 rounds all in the 2 MOA ring, then-

4). Ten single shots, 10 seconds per shot. Start standing, go to prone on the start of time, shoot one shot in 10 seconds, then stand back up and start over. Goal is 10sgits consistently under time for each shot, and all inside the 2 MOA circle.


After you have got those consistently, then:


5). Start over at #1 and do it off of a pack using your field equipment.





You have to start at the beginning and then go from there adding one task in at a time. Get control of each task before moving on.

 

[TX_Diver]

1). Lay down in the stable rest and shoot 3x ten round groups. Let the barrel cool between groups (for barrel mirage reasons). Zero off of that.

2). Take the cone of the 30 shot groups and use that as the target. Then, break and build the position practicing until you are keeping all shots inside the cone- think bullseye shooting. You could use a NRA B8 bull, but legitimately the S2H target was made for this. You’re looking for a 100pt-10x score for ten rounds if using a B8, and everything inside the 2 MOA circle with the S2H target.

3). Do the exact same above, start standing then go to prone and make it 30 seconds for 5 rounds per string- do this twice for a 10 round group. Again, once you are consistently doing 10 rounds all in the 2 MOA ring, then-

4). Ten single shots, 10 seconds per shot. Start standing, go to prone on the start of time, shoot one shot in 10 seconds, then stand back up and start over. Goal is 10sgits consistently under time for each shot, and all inside the 2 MOA circle.


After you have got those consistently, then:


5). Start over at #1 and do it off of a pack using your field equipment.





You have to start at the beginning and then go from there adding one task in at a time. Get control of each task before moving on.

Thanks.

Do you recommend this whole string with each rifle? Or if I can get steps 1-5 done with the .223 would I be able to zero the 6.5cm via step 1 then jump to step 5 as some of the other steps seem to be skills based rather than equipment based and I assume there's some carry over?

 

[Formidilosus]

Thanks.

Do you recommend this whole string with each rifle? Or if I can get steps 1-5 done with the .223 would I be able to zero the 6.5cm via step 1 then jump to step 5 as some of the other steps seem to be skills based rather than equipment based and I assume there's some carry over?

You can do it with any rifle- the 223 just makes seeing your errors easier.

 

[TX_Diver]

1). Lay down in the stable rest and shoot 3x ten round groups. Let the barrel cool between groups (for barrel mirage reasons). Zero off of that.

2). Take the cone of the 30 shot groups and use that as the target. Then, break and build the position practicing until you are keeping all shots inside the cone- think bullseye shooting. You could use a NRA B8 bull, but legitimately the S2H target was made for this. You’re looking for a 100pt-10x score for ten rounds if using a B8, and everything inside the 2 MOA circle with the S2H target.

3). Do the exact same above, start standing then go to prone and make it 30 seconds for 5 rounds per string- do this twice for a 10 round group. Again, once you are consistently doing 10 rounds all in the 2 MOA ring, then-

4). Ten single shots, 10 seconds per shot. Start standing, go to prone on the start of time, shoot one shot in 10 seconds, then stand back up and start over. Goal is 10sgits consistently under time for each shot, and all inside the 2 MOA circle.


After you have got those consistently, then:


5). Start over at #1 and do it off of a pack using your field equipment.





You have to start at the beginning and then go from there adding one task in at a time. Get control of each task before moving on.

Started the first part of step 1 yesterday. Will keep updating this as I go along and see how it plays out. My hope is to do a lot of the practice with the .223 then verify with the 6.5cm that I can keep the same center of the cone from a stable rest at the range and in the field.

Initial impression is that from my more stable rest (pint size gamechanger taped to a full ammo box) I am .1 to .2 right of what I shoot off a pack, but will get to 30 rounds then see if it still looks that way. The handloads are being shot for comparison mainly to figure out the zero offset. Will also get to 30 rds of each and then see.

These groups were shot 3rds, 3rds, 2rds, 2rds, with shooting the .223 in between each target to keep the barrel/can cool. Mild mirage from the can on the last 2 shots of each, but no ground mirage.

 

[TX_Diver]

Shot another 10 rounds of each today. This time I shot 5 round groups 2x. I shot the hunter drill w/ the .223 in between each 5 round group to keep things cooler. By shot 5 of each though there was some level of mirage so for the next one I'll do 4/4/3.

I'm testing 2 things here.
1 - POI difference between my handloads (on right and factory ammo on left).
2 - POI difference between a solid rest at the range and shooting off my pack.

The 10/16 targets are in the previous post and were shot off an ammo box with a pint size game changer taped to it. The top 10/26 targets were shot the same way and the bottom one was shot off my pack with a molinator tied to it and my bino harness as a rear bag.

I'm down to 10 rounds of my handloads left and have a local hunt in a few weeks so I'm going to get through that then I'll shoot one more group with whatever's left to finish out Test 1.

Test 2 really just started today with my first group off the pack. So far it doesn't seem like there's a difference, but I'll get to 30 rounds of each and then compare (and adjust zero for the new ammo).

I'm uncertain if I'm going to adjust zero .2 mil left with my handloads until I finish 30 rounds of the factory ammo and compare the impact from pack vs solid rest.

 

[TX_Diver]

All overlaid on one sheet. I'll add the remaining groups to this same page when I shoot them too.