Gunsmithing Barrel Issue?

[Getagrip_customs]

So I recently had a Hawkhill barrel spun up for my dasher. I run a pretty light load of 30.6gr of varget pushing atips right at 2800fps. This is a load I’ve ran in my last 3 barrels and all have seemed to love it.

I threaded this new barrel on and put about 200 rounds of copper creek dasher ammo through it for break in before the NRL barrelburner match so I wouldn’t hit a speed up in the middle of the match.
I tested a little with my old load to make sure it still liked it and it shot ragged hole groups at the 2797 with 3 sd. Needless too say I was satisfied.

well I get too The match and day one, stage one I start having issues. I begin missing targets that’s I shouldn’t be missing and and would hit for the first half of the stages. Most of day one was positional and 12 round stages so I was in a pinch for time but I was missing a lot more than I normally do. I made sure I was making clean breaks but just figured it was me not having a good day. Day one was hot with tricky winds that weren’t necessary high winds, just switchy. The mirage was on the next level so seeing exactly where I was hitting on the targets were tough and getting true miss measurements were a bit of a struggle.
Day one finishes and I had shot so poorly and couldn’t really put a finger on what was wrong so I shrugged it off and tried to clear my head for day two. The only thing that I could gather from day one was all of my misses came in the last half of each stage.

day two starts and I’m the first up on my first stage. We had 3 fresh big unshot targets At 600 yards and it was prone so I was hoping to get a clean stage or atleast an idea of what’s going on. The stage starts and Icenter punched the first 5 -6 rounds and the last 4-5 rounds I start missing high. I was trying to make corrections but it seemed like I couldn’t correct enough. Round 6 would be .2 high, round 7-8 would be .3-.4 high and rounds 9,10 would be minimum of .5+ high.

At this point I knew that the issue wasn’t me making fundamental errors and there was an issue with my rifle. For the remaining stages I would have too take out elevation from my dope half way through out each stage to get more impacts. It’s like once my barrel heats up on every stage it starts too climb way high But when it cools down my actual dope is dead on...

Has anyone had this issue before or know what might be causing it if it’s not the barrel?

 

[aljones_315]

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[myronman3]

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hey look here, stretchnutz..... what’s the big idea of trying to commender my profile picture???

 

[kindabitey]

Lots of missing info. Did you check all of the obvious stuff like scope rail, rings/ mount, chassis/ stock screws, etc. No mention of action type/ brand.

 

[Getagrip_customs]

Lots of missing info. Did you check all of the obvious stuff like scope rail, rings/ mount, chassis/ stock screws, etc. No mention of action type/ brand.

Yes my bad. Everything has been torqued too spec and double checked.

Impact action, xlr envypro chassis, ZCO scope, mpa unimount.

 

[morganlamprecht]

can you replicate the shift at 100 yds?

shoot it at 100, not getting it hot...bang the barrel fairly hard up/down/left/right...the POI shouldnt ever move...if it does, theres a rifle problem...if it doesnt, get it hot like you would on a stage and look for the same shift

 

[whatsupdoc]

What bullet ? Check the barrel twist.

 

[FisherT&C]

Barrel mirage compounded with actual mirage could make the target appear higher for sure, creating high misses. Try to replicate the problem on a cooler day.

 

[Getagrip_customs]

What bullet ? Check the barrel twist.

Hornady 6mm 110 Atips in a 26” 7.5 twist. I haven’t had this issue in any of my 7.5 twist barrels.

 

[Getagrip_customs]

Barrel mirage compounded with actual mirage could make the target appear higher for sure, creating high misses. Try to replicate the problem on a cooler day.

That actually makes more sense than the barrel just gaining elevation as the temp goes up. This is my first match with the ZCO and i did notice that it doesn’t cut through the mirage aswell as my tangent does. I may test that aswell.

 

[Getagrip_customs]

can you replicate the shift at 100 yds?

shoot it at 100, not getting it hot...bang the barrel fairly hard up/down/left/right...the POI shouldnt ever move...if it does, theres a rifle problem...if it doesnt, get it hot like you would on a stage and look for the same shift

I haven’t been out since the match but I’ll test it that way aswell next time i go out.

 

[Raufoss]

Carbon ring . Have you looked for one?

 

[Livetoohunt]

Just put a zero comp scope on my 7 mag with spur mount and having some of the same issues.Rifle normally shoots great and have spent the last couple of days looking at all the obvious issues.I’m sure not going to say it’s the scope but after reading this I’m going to put another scope on my rifle just to make sure.

 

[308pirate]

What bullet ? Check the barrel twist.

Wtf

Completely off base

 

[Greg Langelius *]

Roll a sheet of dark (black?) construction paper into a tube that fits onto the objective bell and extends to just above the muzzle.

If the problem disappears, it's barrel mirage. To resolve, try a mirage band.

Greg

 

[whatsupdoc]

Wtf

Completely off base

Not really, if the twist is too slow it will do stupid stuff like the OP is seeing.

 

[308pirate]

Not really, if the twist is too slow it will do stupid stuff like the OP is seeing.

The OP is seeing a repeatable pattern to POI rise.

When bullets are not stabilized in flight, their behavior is anything but repeatable.

 

[whatsupdoc]

The OP is seeing a repeatable pattern to POI rise.

When bullets are not stabilized in flight, their behavior is anything but repeatable.

Looks like you are correct, seems I did not read the entire post.

 

[Getagrip_customs]

Just put a zero comp scope on my 7 mag with spur mount and having some of the same issues.Rifle normally shoots great and have spent the last couple of days looking at all the obvious issues.I’m sure not going to say it’s the scope but after reading this I’m going to put another scope on my rifle just to make sure.

I’m headed out tomorrow too test everything. There was a minor carbon ring built up but nothing bad enough to really raise concern. I put my tangent back on to see if the issue still occurs. I’ll report back with what I find.

 

[Kadams1563]

We’re the other barrels all Hawk hill? You wouldn’t be the first person to have issues with them.

any pressure signs on brass and what is the barrel profile? (May have missed that part)

 

[Getagrip_customs]

We’re the other barrels all Hawk hill? You wouldn’t be the first person to have issues with them.

any pressure signs on brass and what is the barrel profile? (May have missed that part)

No the other barrels were benchmark vcc barrels and proof CC barrels. This is the first Hawkhill I’ve had.