splitting the difference cold/warm barrel question..

[victorpolyakov33]

Kind of a long question but I feel the backstorry is important to understand it... My gun is zeroed at 100yrds. When my gun is cold bore/first shot it hits above the bullseye, and then all consecutive shots hit bullseye..(half inch difference from cold bore to warm bore) so I adjusted my zero to split the difference that way my cold bore shot hits top edge of bullseye and all consecutive/ warm bore shots hit bottom edge of bullseye, at 100yrd. This adjustment was 0.50 moa down. Whenever I'm shooting long range to confirm my dope I'm always shooting a "warm barrel" because I'll check my zero first, then I'll shoot 3 shot groups at different ranges (100-700yards). Never shooting a true cold bore at long range. Well my gun is primarily for hunting so the cold bore shot is what really counts.
That's why I think in theory bringing the zero down to split the bullseye would make sense that way at long range the the cold bore shot isn't too high but instead both cold bore and consecutive warm bore shots would be close to where you want to be hitting your target... The question is.. since I've never truly checked my dope with a cold barrel but only warm... by splitting the difference from cold bore and warm bore in theory my dope should stay the same? Bringing my cold bore long range shots just above to where my tested warm bore long range shots were? (yes I know the warm bore shots will now be a bit lower as well, but I'm trying to get best of both worlds in the event I need to take a follow up shot on an animal..)
Shooting a 147gr 6.5 creedmoor hornady eldm

Look what I'm looking for isn't an investigation on what could be the culprit on the high POI cold bore shot. Its the gun I've tested it. Im looking for input on whether or not my theory is correct on splitting the difference of warm barrel vs cold barrel shot POI that way I am getting "best of both worlds" in the event that I shoot at an animal 2 or more times... And how this could relate to my Pre established "warm barrel" 700yard long range DOPE. Is the gap in POI shit going to grow at longer distances? or is it going to stay constant 1/2 inch high? I'm not too worried as there is a difference in Acceptable accuracy for real world hunting scenarios vs match grade completion accuracy
I know there is no way to truly know without actually shooting and testing.

 

[Reburn]

Cold bore zero versus (very) Hot bore zero “test”

Discussions around “cold bore shifts” and “cold bore zeroes” versus “warm or hot barrel zeroes” are constant. So is the belief that barrels “walk” when they heat up or that groups open when they heat up. After having multiple discussions, @Ryan Avery and Jake @Unknown Munitions and I set up a...

rokslide.com

 

[mxgsfmdpx]

So the rifle is shooting 1/2” high on the very first shot and then drops down to proper “sight in” every shot after that? What does your 10 shot group look like at sight in yardage?

What rifle and barrel is this? This is quite rare in my experience with good quality rifles and barrels.

 

[victorpolyakov33]

So the rifle is shooting 1/2” high on the very first shot and then drops down to proper “sight in” every shot after that? What does your 10 shot group look like at sight in yardage?

What rifle and barrel is this? This is quite rare in my experience with good quality rifles and barrels.

Ruger american predator in a mdt chassis, vortex strike eagle scope. These guns have thin barrels because its a hunting gun which probably explains the shift as it warms up. Gun shoots consistent 3/4 moa or smaller groups once its warm. For a budget gun with some nice upgrades it kicks ass!

 

[Sandstrom]

Could be cold shooter, try “warming up” with a different rifle first. Also what size are your 10 shot groups?
Ryan

 

[victorpolyakov33]

Could be cold shooter, try “warming up” with a different rifle first. Also what size are your 10 shot groups?
Ryan

I warm up with dry firing to get a feel for gun. Its the gun I've tested the cold bore at 100yards multiple times. I dont have a 10round group size for you. Most ill do is 5 rounds. sub 3/4 moa gun.

 

[victorpolyakov33]

Look what I'm looking for isn't an investigation on what could be the culprit on the high POI cold bore shot. Its the gun I've tested it. Im looking for input on whether or not my theory is correct on splitting the difference of warm barrel vs cold barrel shot POI that way I am getting "best of both worlds" in the event that I shoot at an animal 2 or more times... And how this could relate to my Pre established "warm barrel" 700yard long range DOPE. Is the gap in POI shit going to grow at longer distances? or is it going to stay constant 1/2 in high? I'm not too worried as there is a difference in Acceptable accuracy for real world hunting scenarios vs match grade competition accuracy
I know there is no way to truly know without actually shooting and testing.

 

[Formidilosus]

Look what I'm looking for isn't an investigation on what could be the culprit on the high POI cold bore shot. Its the gun I've tested it. Im looking for input on whether or not my theory is correct on splitting the difference of warm barrel vs cold barrel shot POI that way I am getting "best of both worlds" in the event that I shoot at an animal 2 or more times... And how this could relate to my Pre established "warm barrel" 700yard long range DOPE. Is the gap in POI shit going to grow at longer distances? or is it going to stay constant 1/2 in high? I'm not too worried as there is a difference in Acceptable accuracy for real world hunting scenarios vs match grade completion accuracy
I know there is no way to truly know without actually shooting and testing.

The reason you are getting the responses you are, is because what describing doesn’t exist. They are asking for more information, because I side their questions are the actual answers you need.
Rifles do not put the first shot exactly and every time 1/2 MOA high, then magically drop 1/2 MOA and stay there. If you have a shift from “cold bore” to “hot bore”, it doesn’t just magically jump and stay- it gradually moves as the barrel heats up and it mean that you have a mechanical problem with the rifle.

I warm up with dry firing to get a feel for gun. Its the gun I've tested the cold bore at 100yards multiple times. I dont have a 10round group size for you. Most ill do is 5 rounds. sub 3/4 moa gun.

So it’s “sub 3/4 MOA gun” every single group? And those groups are always perfectly centered over your aiming point? Of course it isn’t, and they aren’t. If you shoot 10 plus rounds at a single aiming point on a single target, you will see two things- it isn’t a 3/4 MOA rifle, and your cold bore shot is randomly located somewhere inside the cone of all ten rounds.

 

[Wrench]

.....or, you have shot anticipation that causes some mild form change that you get over after the first bang.

Or both.

 

[Sandstrom]

I would highly recommend you check out the Hornaday pod cast #50, “your groups are too small”. It is very informative and helps explain what is more than likely going on for you. Or it is a flinch, or mechanical problem.
Ryan

 

[poboy2214]

I have the exact same problem with a different rifle only a little more exaggerated (1st shot at 2” at 100 yds, then back down to 3/4” MOA). This has happened exactly the same the past 6 times I’ve been to the range. I’ve shot this same rifle for seven years and it didn’t start until last year. Doing further research people have suggested it happens more significantly with a clean bore versus a fouled one which in my scenario makes a little more sense given that I don’t clean my rifle often but I give it a thorough cleaning last year. I am no expert so don’t take it from me, but I got on this thread looking for answers to the same question and that’s what’s made the most sense so far.

 

[Sandstrom]

I have the exact same problem with a different rifle only a little more exaggerated (1st shot at 2” at 100 yds, then back down to 3/4” MOA). This has happened exactly the same the past 6 times I’ve been to the range. I’ve shot this same rifle for seven years and it didn’t start until last year. Doing further research people have suggested it happens more significantly with a clean bore versus a fouled one which in my scenario makes a little more sense given that I don’t clean my rifle often but I give it a thorough cleaning last year. I am no expert so don’t take it from me, but I got on this thread looking for answers to the same question and that’s what’s made the most sense so far.

It sounds like you only cleaned your rifle once last year, it should get back into being “fouled” after a few shots. If your problem has continued after 6 range trips it is likely something else. Please give more details about your gun, including what scope and rings, brand of ammo(same lot?), rifle model and caliber. First thing I would check is that all action screws and scope mounting screws are degreased and torqued properly. Second, what is the size of your 10 shot no b.s. group.

Ryan

 

[Billy Goat]

I have the exact same problem with a different rifle only a little more exaggerated (1st shot at 2” at 100 yds, then back down to 3/4” MOA). This has happened exactly the same the past 6 times I’ve been to the range. I’ve shot this same rifle for seven years and it didn’t start until last year. Doing further research people have suggested it happens more significantly with a clean bore versus a fouled one which in my scenario makes a little more sense given that I don’t clean my rifle often but I give it a thorough cleaning last year. I am no expert so don’t take it from me, but I got on this thread looking for answers to the same question and that’s what’s made the most sense so far.

Scope wandering in transport, first shot sets the erector where it should be is my bet.


It's not terribly uncommon, and is frequently the blame of the "cold bore" shot being off.

If your cold bore shot is off, something is wrong. Shooter, scope, or rifle. Chances are likely in that order.

 

[SloppyJ]

He came for what he thought was an easy answer....

 

[Reburn]

He came for what he thought was an easy answer....

I know in my heart that I shouldn't engage in these threads as nobody ever listens.
They are just looking for validation.
but apparently I'm a sucker for punishment.

I like to remember what Form said. We miss due to these reasons in this order.
1) we suck
2) didnt have a zero at all
3a) scope lost zero
3b) rifle lost zero
4) zero wasnt optimal
5) wind call

 

[Billy Goat]

I know in my heart that I shouldn't engage in these threads as nobody ever listens.
They are just looking for validation.
but apparently I'm a sucker for punishment.

I like to remember what Form said. We miss due to these reasons in this order.
1) we suck
2) didnt have a zero at all
3a) scope lost zero
3b) rifle lost zero
4) zero wasnt optimal
5) wind call

#1 and #5 should just be combined with an @.

1) I suck @ wind call

 

[Reburn]

#1 and #5 should just be combined with an @.

1) I suck @ wind call

Agreed.

2-4 reasons should not exist.
There is so much data just here how to elimnate them.
Yet, people dont listen.

#1 and #5 get me frequently. I eliminated #2-4 from being variables.

 

[Marbles]

#1 and #5 should just be combined with an @.

1) I suck @ wind call

But, so many people blame just poor shooting in general an poor wind calls that combining the two risks avoiding correction of the actual problem.

#1 covers
-I flinch because my cartridge is too big and my gun too light
-I'm jerking the trigger
-I cannot build a stable shooting platform without a bench at the range
-Etc

Those basics are probably the problem more often than wind calls.

 

[poboy2214]

Scope wandering in transport, first shot sets the erector where it should be is my bet.


It's not terribly uncommon, and is frequently the blame of the "cold bore" shot being off.

If your cold bore shot is off, something is wrong. Shooter, scope, or rifle. Chances are likely in that order.

So the fix should be tightening the screws? I'm not a sniper by any means but for it to be consistently in the same place on the first shot every time makes me think it's not just me.

 

[poboy2214]

It sounds like you only cleaned your rifle once last year, it should get back into being “fouled” after a few shots. If your problem has continued after 6 range trips it is likely something else. Please give more details about your gun, including what scope and rings, brand of ammo(same lot?), rifle model and caliber. First thing I would check is that all action screws and scope mounting screws are degreased and torqued properly. Second, what is the size of your 10 shot no b.s. group.

Ryan

Savage model 111 30-06, shooting remington core lokt 180 grn. Nikon BDC scope with the factory rings (not sure what brand, bought this rifle/scope as a package). 1.5" group, usually pulling down to the left. TIA