30 Cal 260's

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Jon A, Feb 12, 2011.

  1. Jon A

    Jon A Well-Known Member

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    Here are three bullets elkaholic made for me to test. I figured you guys might like a pic:

    [​IMG]

    From left: 208 A-Max, 240 SMK, 260 with a bronze tip, 260 with an aluminum tip, and one that's bonded, also with an aluminum tip (black marker on the tip just so I don't get them mixed up).

    I plan to shoot them tomorrow to see if they make it to the target in one piece out of my 1-8. Wish me luck!
     
  2. Camshaft

    Camshaft Well-Known Member

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    good god thats a lot of bearing surface.
     

  3. Jon A

    Jon A Well-Known Member

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    Only a bit longer than the 240's and this rifle has always loved those (all three of its barrels).
     
  4. Camshaft

    Camshaft Well-Known Member

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    What kind of BC are you thinking with say a 2750 launch speed. I'm getting ready to order 2 barrels and if these look promising I will go ahead and order one in an 8 twist. Please keep me posted
     
  5. elkaholic

    elkaholic Well-Known Member

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    Jon....This is going be interesting! The jury is out as to if even the bonded one will hold up? If it doesn't, I have an idea that I think will work but it may only be a 250 grainer (dinky)! The calculated B.C. is .840. Make sure no one is standing off to the side in case you don't have a tight enough CHOKE:D....Rich
     
  6. elkaholic

    elkaholic Well-Known Member

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    Jon....This is going be interesting! The jury is out as to if even the bonded one will hold up? If it doesn't, I have an idea that I think will work but it may only be a 250 grainer (dinky)! Make sure no one is standing off to the side in case you don't have a tight enough CHOKE:D....Rich
     
  7. Jon A

    Jon A Well-Known Member

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    Success! All three made it to the target (100 yds) and made round holes! And even though they were different types they formed a group only a bit over 1" which shows there may be some good accuracy potential there if I shoot three of the same type. In any case they weren't "all over the target" which has happened to me before with bullets less than stable.

    Of course I started with a conservative 94 grains of US 869 which is probably a good 100 fps under max at least. I'll have to see what happens when I start adding powder....
     
  8. groper

    groper Well-Known Member

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    Nice... Id hazard a guess and say the AL tipped ones would stabilize from a 1:9twist thanks to the reduced transverse moment of inertia. The increased fineness ratio of the nose also moves the center of pressure aft aswell...

    The bronze tips, would probably need the full 1:8 or maybe 8.5twist...

    I was looking at making some high BC bullets in 30cal, but noone seemed to have the barrels to shoot them... maybe this will catch on and a few more people will order some faster twist barrels for the big 30`s...?
     
  9. elkaholic

    elkaholic Well-Known Member

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    CONGRATS! and you didn't kill any bystanders. I didn't take a whole lot of care in making those samples, as I previously told you, so I am encouraged that they shot that well! The weights weren't very consistent and in fact the ballistic tips are seven grains difference. Lets make a consistent lot now and give it another go. I had already made one with a heavier jacket in case these failed but it sounds like we won't need it. The ones I sent would be "one devastating" long range bullet because they will expand at low velocity...Rich
     
  10. jmden

    jmden Well-Known Member

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    Wow, Jon and Rich--great news and good work! Keep us informed.
     
  11. jwp475

    jwp475 Well-Known Member

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    The non tipped 265 grain bullets that Richard made when he owned Wildcat bullet needed an 8 twist to stabilize and that is why I built my 300 RUM with an 8 twist

    Very high BC bullets need more twist
     
  12. elkaholic

    elkaholic Well-Known Member

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    These bullets are nearly 1.9" long and at the velocities that they can be fired at, I am pretty sure an 8 twist is necessary, especially at the extreme ranges for which they are intended......Rich
     
  13. Camshaft

    Camshaft Well-Known Member

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    So is ordering an 8twist barrel a must or is a 9twist ok?
     
  14. pitbull320

    pitbull320 Well-Known Member

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    I have some of the 265 wild cat,s and I have a 300 rum with a 1-10 and they shoot just fine they are 1.750 in length I also shoot the 220 hat,s and they are 1.786 both these bullets shoot outstanding especially the 265 wild cat,s in fact my dad shot his deer with a 265 wild cat at 556yrds and it flat out dropped him you will be surprised on what a 1-10 will shot