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Discussion Starter #1
I am venturing into the world of heavy LGC bullets for my .454 Casull, and want to try 360 gr LGC bullets. Can I shoot them as SLOW as 1100 fps and still have the 1:24 twist stabilize them?


All of the data on Loadswap shows good accuracy, but is over 1400 fps.

The idea is to duplicate the Taylor KO factor for the factory 300 JFP at lower velocity and recoil. Can't imagine needing anything over 50 TKO with the .252 SD and diameter of this bullet. 1100 to 1150 fps will do the job.

Thanks
 

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The Hog Whisperer (Administrator)
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Hi Loader,

I shoot 340's in my Bisley Blackhawk, and I have gotten good accuracy at lower velocities than that, around 1,000fps.

Only catch is, I don't know what the standard Blackhawk twist rate is. Obviously my bullets were lighter, but close to what you wanted to use.

If the Blackhawk twist rate is the same as you are asking about, I'd say it will probably work. Hopefully someone knows off the top of their head.
 

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Generally speaking, slowing down a bullet will not affect stabilazation. If it shoots at 1400 it should shoot just as well at 1000. The reverse doesn't seem to hold true.
 

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I should qualify my last post, I have much more experance with jacketed bullets and small bore varmint rifles. I could very well be wrong about cast bullets. But I don't think that they can be all that different. I need to try some heavy cast in my F/A .454
 

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Discussion Starter #5
Mike -

If your Bisley is a 45 Long Colt, it could be as fast as 1:15.

Snake RR -

We can WAG requied twist rates from multiplying the square of the bore times 150. This gives the rate of optimal twist for a bullet 1 inch in length. At .452 caliber we get a twist rate of 1:30.6 inches to start out, knowing nothing of velocity effects. From there we can scale up or down based on the actual length. All of this is for a reference velocity based on bullet shape.

The more mass carried in the outer portion of the bullet diameter, the better. Hence, hollow points are better, because they carry less of the lead in the portions of the bullet that are less than full diameter. The same holds true for pistol bullets of FN design. The reference velocity for FNs appears to be around 2000 fps, from what I gather.

So, if we addditionally correct for velocity, we take the square root of the ratio of the reference velocity to the actual velocity. Here, we are talking the sq root of 1100/2000, or about 0.74.

So, 30.6 times 0.74 gives us a twist rate of 1:22.6 inches for a 1 inch long .452 FN bullet. The actual length of the 360 GCFN is not yet know, as I have not selected it, but I may be OK at 1100 fps and 1:24.

If you do shoot some of these @ 1100 fps, please let me know how they work out.
 
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