stretching 375 H@H cases

[canuck4570]

just bought a brand new Sako Kodiak in 375 H@H
if I measure factory ammo with a calliper and stoney point attachment before firing and after firing the stretch some .020
is this normal
the measurement is taken from the base of the bullet and end of shoulder

 

[Stimpylu32]

just bought a brand new Sako Kodiak in 375 H@H
if I measure factory ammo with a calliper and stoney point attachment before firing and after firing the stretch some .020
is this normal
the measurement is taken from the base of the bullet and end of shoulder

If you mean from the base of the case then .020 is not out of the question , you may have a rifle that has had its chamber cut with a new reamer and is a tad on the high side of the spec. also factory ammo is made to function in many , many different sized chambers .

You could also have a sight head space issue were the barrel may need to be set back a fuzz . ( worst case senareo )

stimpy

 

[BoydAllen]

Actually, that is pretty typical of belted cases, just make sure that you set your die for shoulder bump, just like you were shooting a rimless case. Because the headspace is at the belt, and there is not standard head to shoulder dimension for belted cases, case and die makers locate shoulders far enough back to work with all the different versions of a particular caliber. This is only a problem if you set the die to touch the shell holder, repeatedly pushing the shoulder back and then stretching it every time it is fired. If this only happens the first time that the case is fired, there is no problem.

 

[canuck4570]

the shoulder is stretch out by .015 to .020
made some research and yes this is normal
has mentioned by BoydAallen you have to make certain that you adjust your die in a way than you bump back the shoulder about .002 on a fired case
this way further stretching will be kept to a minimum