My first 6mmAI is on the way .....

[Aussie]

Re: MSU- here is what I worked up...

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it is not with the bullet weight that you menitoned, but run the ballistics on the computer...very impressive

26" shilen SM barrel

Win brass-FIRE FORMING LOADS
Fed 210 or 9 1/2
70g Ballistic tip
50.5g of Win 760
4050 fps with single digit SD and .385 groups

Formed loads
51.5g of 760
70g Nosler BT
4150 fps
bug hole groups

Work up to these loads in your rifle.

It is amazing how this much speed will cut down on wind drift and bullet drop to 550, after that the heavier bullet will take over on wind drift, but bullet drop is horendous.

For the heavier bullets, I wouild start off with R#19 and close to max pressures you will find an accuracy load.

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Keith ,
Those velocities are a good 300 FPS beyond maximum quoted in reloading manuals for the larger .240 Weatherby using 760 and 70gn projectiles although your powder charge is about 1gn lower .
6mmAI is usually good for about 100 FPS over .243 AI . My 26 inch .243AI topped out just under 3700 FPS with 760 and the 70gn Nosler .
Might be a good idea to check your chronograph because unless the 6mmAI defies the laws of physics then those numbers just don't seem to stack up .

 

[coyotekiller]

Re: MSU- here is what I worked up...

I just got brass formed and a load shooting yesterday in my new 6mm ack. I have not had time to chrono it yet but 43.5gr of varget behind a 87gr vmax shoots little holes out of my 24" shilen 10 twist.
To form the brass I shoot 39.0gr of varget with the 87gr hornady hollow point. It is not a fast load but it forms the brass very well.

 

[CatShooter]

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Twist rate can effect your loads? Thats news to me. The twist will be a 1-9.

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Yes twist rate does effect your loads, for example if you have a 1-10" to 1-12" twist you could load w760 and shoot 70gr BT's at close to 4000fps (keithcandlers estimates of 4150fps are a bit optomistic and closer to the second coming of Chernobyl rather than reality). since you later stated that you have a 1-9" twist your best bet would be to try H4831,RL22 or VVN165 and use a Berger 95gr VLD. with a B.C. of .514 acombo that would be hard to beat

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That's NEWS to me too.

If he has a 9" twist, and wants to shoot 87 V-Maxs and 90 Bergers, the rate of twist does NOT effect the powder choice or the loading data.

He can use whatever powder he wants... and if he had a 10" twist, or an 8" twist, the loading data for his choice of bullets would not change.

.

 

[Aussie]

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Twist rate can effect your loads? Thats new's to me. The twist will be a 1-9.

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Yes twist rate does effect your loads, for example if you have a 1-10" to 1-12" twist you could load w760 and shoot 70gr BT's at close to 4000fps (keithcandlers estimates of 4150fps are a bit optomistic and closer to the second coming of Chernobyl rather than reality). since you later stated that you have a 1-9" twist your best bet would be to try H4831,RL22 or VVN165 and use a Berger 95gr VLD. with a B.C. of .514 acombo that would be hard to beat

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Just be aware that the 95gn Berger doesn't seem to like velocities above about 3150 FPS . Doesn't disintegrate but accuracy goes off .