28 nosler, vapor trailing?

HARPERC

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Jan 28, 2011
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Spokane, WA
....Very interesting! I wouldnt have thought of that.....
There is a video here of Kirby Allen shooting a whitetail with an excellent trail.

Steve reports it was an oil they used early on, and have since switched. Trails still present at range, but not as dramatic.

The video is unique in that it's a 100 yards. Most video of trails are at long range. Setting the target lower in the view gives you opportunity pick up the bullet earlier as it's drops into the FOV. As has been said slightly out of focus helps.

The appearance of curving is interesting, something in the photography??? Didn't key hole, how were groups?
 
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May 5, 2020
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Indiana
There is a video here of Kirby Allen shooting a whitetail with an excellent trail.

Steve reports it was an oil they used early on, and have since switched. Trails still present at range, but not as dramatic.

The video is unique in that it's a 100 yards. Most video of trails are at long range. Setting the target lower in the view gives you opportunity pick up the bullet earlier as it's drops into the FOV. As has been said slightly out of focus helps.

The appearance of curving is interesting, something in the photography??? Didn't key hole, how were groups?
these were my first rounds out of the gun for barrel break in and was only shooting 2 bullets of each powder load but 2 of them were right at 3/8 and rest of them between .75-1.25.
 

David Emerson

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Jan 1, 2020
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Drayton,ND
I’ve had a hankering for a long time for a 28 nosler so I finally made a dream come true and went out and bought a seekins havak (it does have the seekins brake). I finally got her all dressed up with a leupold lrp and loaded up some adg brass from 78-81.5 h1000 shooting 169 hammer hunters looking for pressures and breaking in the barrel (the hammers do require a 1-8.5 and the Havak is a 1-8.6 but there was no key holing?)
While shooting my father noticed you could literally see a spiraled trail all the way too 100 yards but it was at the blink of an eye. I shot two of each loadings at .5 grain increments and managed to get this still frame picture of what im talking about in a video that is attached.
So what is causing this?
Sorry bout the ignorance just never had this happen before with any other Rifle before.
Thanks!
Humidity and temp and pressure were just right.
 

hoffbill

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Dec 21, 2013
Messages
23
Regarding twist rate the often overlooked variable is velocity. Twist rate combined with velocity determine the RPM of the bullet leaving the barrel. Every bullet has a minimum needed to be stable as well as an optimum for maximum stability. Excessive RPM's can result in bullet deforming or disintegrating. The reason heavier bullets may require faster twist rate than a lighter bullet of the same caliber and design is that the heavier bullet will generally have less velocity, thus requiring faster twist to achieve the same RPM. If you play with the math of twist rate, velocity and convert to RPM you will see that most bullets are in the 190,000 to 200,000 RPM range.

or
How to Calculate RPM - Calculating the RPM of a Moving Bullet

  • Determine the muzzle velocity of the bullet.
  • Determine the twist rate imparted by the barrel.
  • Convert the muzzle velocity into the same unit per second as the unit of the twist rate.
  • Divide by the result by the length of the twist rate.
  • Multiply by 60.
 
Last edited:

yorke-1

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Jul 5, 2008
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Location
Clearwood, WA
Like others have said, it’s the cutting oil. I’ve had old batches of Hammers show some pretty spectacular vapor trails; I thought it was kind of cool. The newer batches of bullets don’t have nearly the same trail.
 

Ingwe

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Jul 3, 2011
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948
You’ll hear from someone in the hammer camp that shoots 4000 FPS 300wsms or 3600 FPS 280 ai soon.


The oil residue in the hollow point cavity seems most likely to me. I highly doubt a 1:8.6 at 28 Nosler speeds is shredding them.



That is unless you’re shooting that 169 Hammer at 4000 FPS? Honestly wouldn’t surprise me given the Hammer camps most recent “data”



Best of luck, sweet rifle, awesome t shirt
Wonderful informative response for a kid asking a valid question

Way to go, hope you feel better
 

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