50-110win 1 in 15 twist barrel

There are probably more modern up-to-date formulae, but as an old guy the Greenhill Formula from 1879 still works for me.

Optimal twist rate = 150 X (calibre in inches squared) divided by bullet length in inches.
Optimal bullet length = 150 X (calibre in inches squared) divided by twist rate in inches.
So all you need is your bullet length, and likely .512 as calibre.

Just edited as I found a 440gr. cast bullet advertised as .865" in length at .512" diameter, which works out to needing an optimum 1 in 45.45" twist rate,
so 1 in 15 is too fast for that bullet.
 
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It is faster than is required but that does not mean it is too fast. I have had .45's with a 14 twist which shot best with 300 grain bullets. A thirty inch twist would have been adequate.
 
reason I asked the question is I can get a 50cal barrel for cheap but its 1 in 15 twist and I don't want to buy it if it wont work, So you think it will work ok?
 
I can't speak to the quality of the barrel but, if it doesn't work, it isn't likely to be because of the twist.
 
Mr Leeper is right.. better always to have a faster twist than a slower one..
Don't ever remember hearing of a bullet over stabilized but under is common enough..
As an example .Some 223's in 7 twist shoot 50 great bullets really nicely...
 
A fast twist wont overstabilize a bullet. The real concern is light, varmint weight bullets such as a 35gr or 40gr bullet in 223ish cals being spun so fast, that the jacket spins apart with massive centrifical force. Not an issue with any 50cal jacketed bullets I can imagine. You are good to go. I have 2 rifles in 444 marlin. One a first year with a 1:38" twist. The second is a later gun with a 1:20" twist. The faster twist barrel shoots every weight bullet better.
 
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