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Balistic question for you guys

05 Nov 2015
@ 02:41 am (GMT)

john feyereisn

I am not sure how to come up with an answer to the following so i can satisfy my own curiosity.
My brother Zeroed his new 3006 with remington 150 corelokt ultra factory loads, then switched to hornady superformance 150 sst loads. At 200 yds the ssts are hitting 9 inches higher than the remingtons.
Sst bc is .415 at 2920 fps advertised
Corlokt ultra bc is .331 at 2910 advertised
Assuming the bcs are close to accurate and the velocity on the hornady ammo is accurate what would the muzzle velocity have to be to hit 9 inches low at 200 yds?
I was suprised to see that much difference, i am guessing the remintons are lower velocity than advertised and i may rin them over a chrono to verify, but if anyone has another explination i would be intersted to hear it.


05 Nov 2015
@ 04:20 am (GMT)

Chris Murphy

Re: Balistic question for you guys
couple of things John. the SF could be going (faster my mate got an extra 150fps than advertised in his 270, with completely flattened primers).
and the Rems could be going slower and with lower BC slowing down faster.
also the barrel harmonics could have them grouping a couple inch different at 100 as well especially if its a thin barrel and if all this happened together who knows.
05 Nov 2015
@ 01:28 pm (GMT)

john feyereisn

Re: Balistic question for you guys
mystery solved!
he bought the rifle from his father in law, who gave him the remnants of the last few boxes of ammo with it, at some point somehow, he or the father in law got the ammo in the wrong boxes. they were actually 180 gr not the 150s he thought.
05 Nov 2015
@ 01:56 pm (GMT)

Alvaro Piqueras Alonso-Lamberti

Re: Balistic question for you guys
Hi John;

Even if the ammo boxes were mixed, you can´t expect the heavy bullet to strike lower than the lighter.

For example, I had a 7x64 blaser sighted in for a friend the other day. We test 4 different factory ammo, all of them from RWS.

162 KS (cone point)
159 EVO Evolution (bonded premium bullet)
123 KS (cone point)
126 EVO Green (soft tipped bullet, frangible with tin core... seem to worth some tests for long range hunting...)

I don´t have my chrono data here, but speeds were more or less the same between the lighters and between the heaviers, and of course the lighters were faster than the others.

Both gruped quite well, and the lighters go to clese POI, as the heaviers do, but at a hundred meters, the heavies impact more than 6 inches OVER the others.

If you ask me the cause, the Barrel harmonics is what you have to look at.




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