Re: 22-250AI with 1 in 8 Barrel
I think that it depends more on the barrel and land profile than the twist rate. Kreigers at typicaly 4 groove barrel and they are cut rifled , some folks say that cut rifled barrels are harder on bullets than buttoned one and the 3 groove barrel have shown to be hard on bullet jackets.
This being said , the only real way would be to try it but give Kreiger a call first, I'm sure that somebody their will have an answer.
Or you could give one of the 5R barrel makers a try , either RockCreek , Broughton , Schnieder , Borden all make these type barrels and its said that they don't cause as much harm to bullets as do the other conventionaly grooved barrels and its been proven that they foul less and shoot a bit faster.
As for the twist , I think that the 1-9 would work fine up to 75gr bullet but it is probably on the edge where a 1-8 would be a little more than needed but plenty if you wanted to shoot some 80gr pills.
Now I have seen a 243 with a 1-8 twist shoot 55gr Ballistic tips out at over 4100fps and have no problems with the bullet comming apart and this was from a 6 groove Hart barrel.
SO all in all , I don't think that you should have any trouble with the 22-250Ai blowing them up in a 1-8 twist barrel so long as its a good lapped barrel.
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