Badlands Precision Bullets thread - From BC to terminal ballistics

akmtnhnt

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Nov 21, 2021
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53
Location
Anchorage, AK
I have 125s and 135s but have not have a chance to try them yet. At my altitude of 3300', I'll need 3300 FPS to get SG of 1.5 with 1:8." At sea level, you'll need a ridiculous velocity, i.e., 4900 FPS for an SG of 1.5. I was using Berger's twist calculator.

Have you considered 122 Cayuga? https://patriotvalleyarms.com/flm-6-5mm-122gr-cayuga-hunting-bullets-50ct/. It is meant for 1:8" twist. Good luck!
Ya, I run all my stability at SL, standard, just to be sure, as I do hunt in even denser air than that condition.
 

FEENIX

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Dec 20, 2008
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Great Falls, MT
I was talking to George about the 135s and we think I can get away with a 1:7.5”. That’s going off the jbm calculator.
I think he is right ...

135 BD2 1 75.jpg
 
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phorwath

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Apr 4, 2005
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Alaska
Aluminum and plastic tips allow a lesser tip length than their actual lengths when determining stability. Courtney and Miller conducted tests, and came up with a modified model for tipped bullets, for tip material much lighter than copper/lead.

Patagonia Ballistics ColdBore 1.0 software includes that model in their ballistics software, for tipped bullets.

The Courtney & Miller model only considered stable flight for precision in flight. It didn't address higher stability that might be needed to improve terminal performance in game animals.
 
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Monkeygoat

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Dec 19, 2019
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50
Location
SFBay area, CA
I've got 50 of the 135's and going to try them in my 7.5 twist, 28", 6.5 Max.

Looks like COAL to the lands is 3.1500 - will start with seating depth test .010-.100, considering 55.5 gr 8133 for the seating depth test, since my load for 145 Matchburners is 63 gr.

Welcome any input though - loading them up tomorrow and shooting Sun. Also have N570.
 
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