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JPK:

THANKS for the cites!

Yes, that expounds on the issue and hits on the issue I was referring to. Good stuff. Obviously somebody needs to do a Stem-to-Stern Research Report on it and I need to do some reading!

In sum, I guess it makes sense for a fellow to avoid extremes in the choice of an elephant rifle/cartridge combination, to be sure. An example would be extra heavy monoloithic solids in a rifle with minimal twist. Those details of weight and twist to be determined. I do not know what the original twist rate of the Win African .458 was, but I've always wondered if the accusations of veering penetration could have had something to do with squibb loads{low velocity, low rotational velocity} AND minimal stabilization to begin with. {??}

And for fun...

This quote by Ganyana: "All bullets yaw (helix) - shott a tracer into the night sky and watch".

Here's one launched from my front yard. And before anyone squeals, it is literally 185 miles of dense forest and mountains utterly devoid of buildings, sheds, camps or human habitation in that direction, and there was heavy snow on the ground and mist in the air when the shots were fired.

If a guy can't see the yaw, he ain't lookin'!!

As you know, but some may not, MERELY selecting a bullet based on its heavy weight and extreme length and assuming it to be a deep penetrator can be a mistake. Mere high sectional density does not guarantee deep penetration, bullet construction does. Bob Hagel and Elmer Keith's criticism of the Kynoch 300 grain .333 bullet and my own use and tests of 6.5 cal 160 Hornady's come to mind.

The reason all bullets need more twist in cold air is due to the air presenting a denser medium to the bullet than does warm air. Shooting in deep cold is also very interesting as the shooter can sometimes hear the bullets travel.

Finally...it would be very interesting to add a sticky where we could measure and post actual twists of actual guns instead of relying on catalogs and recurring hearsay. We started one on the gunboards Swede forum and it is a very interesting source of supporting information. I think you stated something about slow twist rates in .416's somewhere.

Standardized twists in military and other rifles normally are tighter than actually necessary for the bullets intended, in order to provide protection against barrel wear; corrosion, erosion, throat erosion, etc. I am REALLY curious as to the actual accuracy of some of the old NE guns that might be used. Testing at say, 50 meters like might occur might not be sufficient to expose bullets that are on the cusp of gyrostatic instability. Assuming there are those shooters who are a bit afraid of the old cannon and only shoot it at 50 meters and don't hit so well anyhow, they may never know until Tembo steps off the blocks!

Now, I wonder what the great collection of NE guns possessed here would expose as to actual twist rates {and bore condition}. I've attempted to measure twists on guns that would not spin the jag due to being shot out...

Thanks for a great discussion and for giving me all the links, etc.

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What are the Rosary, the Cross or the Crucifix other than tools to help maintain the fortress of our faith in Jesus Christ, the Son of God?

Edited by 9ThreeXFifty7 (31/12/08 01:29 AM)

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