AGAIN - Bullet to twist rate - Am I wrong ??

358Scout

358Scout

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Picked up a Shiloh Sharps 45-90 1:21 twist and have a question in regard to best bullet for accuracy.

Shouldn't a bullets flight be determined by length of bearing surface than its weight? It seams to me a longer bearing surface would stabilize quicker.
 
Bearing surface has little if anything to do with needed twist rate.
What IS important is the bullet's length in relation to it's diameter.
Heavier bullets are generally longer than light ones
But a lighter bullet with a sleeker profile may be longer than a "stubby" heavier offering.
Longer bullets require "quicker" twist rates, conversely, short bullets are stabilized with "slower" twist rates.
Regards, Eagleye.
 
Think of stability this way. How fast do you have to spin a pencil to get it to stand on end?

The longer the pencil the bigger the challenge.

If your bullets make round holes at 100 yards, the bullets are stable thereafter. Stability increases as the bullet goes down range, so the challenge is to get them to start off stable.
 
Hi,

Are you certain it's a 1:21 twist? The .45 cal Shiloh's have been 1:18 twist for a number of years now ( unless you custom order something different like a 1:16 which some prefer nowadays ).

Chris.
 
Ganderite said:
Think of stability this way. How fast do you have to spin a pencil to get it to stand on end?

The longer the pencil the bigger the challenge.

If your bullets make round holes at 100 yards, the bullets are stable thereafter. Stability increases as the bullet goes down range, so the challenge is to get them to start off stable.
Click to expand...

I think that the concept of stability increasing with range works for bullets that are supersonic, but from what I understand, BPCR bullets get more unstable with distance. Maybe something to do with being transonic for most of their flight. It doesn't seem to be too uncommon in the long range BPCR world to fight stability issues past 800 yards. I don't know this first hand as I've not yet had the opportunity to shoot my Sharps rifles on paper at that range, but it comes up pretty frequently on the Shiloh site.

Chris.
 
"Gunlaker" Watched youtube and did the same as Potterfeild from Midway explained. I guess I should try it several times to see if its consistant. Unless theres another way?
 
A cleaning rod with bearing in the handle and a tight patch seem to work, at least in the couple of times I've tried it. Does your Shilho have a B in the serial number? If so it's one of the later ones and I think Shiloh will have a record of the options on it including barrel twist ( assuming it wasn't rebarreled ).

Chris.
 
Ah, then your rifle was made before the current owner took over and might have a different twist. I'd try posting on the Shiloh site as there are some guys there with the older rifles and they can probably give you some decent advice on what sort of bullet to use. It'll depend on whether your rifle is one of the ones ith the long freebore or not.

Chris.
 
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