Projectile choice for 2000 yard with 27” 338

[sigstroker]

David Tubb takes it further. He clocks every shot in competition so that if a shot goes low he can see if it had weak velocity, or if he has to look at something else.

[ShaunBrady]

There is no further to take it. Every shot gets chronoed. Tubb came up with a work around for rules banning the Labradar in competition. He addressed the perception that mounting the magnetospeed on the barrel degraded accuracy with an off barrel mount. It definitely shifts the poi, but I didn't see a loss of accuracy.

This is an early NorCal URSA match.



That's Lynn to the right. The gun in front of him is using a Labradar, the next gun has a magnetospeed.

Those were early days, the Labradar had just become available. We hadn't figured out yet that the vertical wasn't just the result of velocity.

[focus]

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Cheers,

[LynnJr]

Shaun Brady,Focus
Dr Ken Oehler has been working on bullet bc variation for decades now. If you space out the screen spacing on a good chronographing 8 feet the accuracy of the unit goes up exponentially. No more +- 5 fps of variation from the chronograph.
What he found out many many years ago was two bullets leaving the barrel at the same initial velocity showed too much spread at 1000 yards so they added polymer, aluminium and bronze tips to those same bullets and reduced the vertical spread considerably.
Meplat trimming and bullet tipping dies quickly became popular to get more uniform BC values with less variation as long as you didn't bulge the bullets in the process.
Vertical spread is what gets tuned for on a benchrest rifle.

The price for the A-tip bullets is in the huge packaging and the sequential sorting.
A box of Sierras when sorted will show the number of dies it took in the 500 count box to make those 500 bullets generally 3 main groups.
Same goes with Berger bullets. I have seen 0.023 variation in a single box of 100 6mm bullets. Those same bullets when bought in sufficient quantity and sorted will shoot lights out. You won't see 23 different groups you will see 4-5 groups with a maximum spread of 0.023 inches. Which means 4-5 different dies where used in the making of those bullets.
Custom bullets from BIB JLK Hottenstein Cauterucio ClinchRiver Spencer Euber Vapor Trail Copperhead and dozens of other sources come off of one die so the ballistic variation is much better than a mass producer using 8 different dies.