300 WSM with 215 Berger Hybrids

[kadillackountry]

I'm in the midst of building my new 300 WSM, long range hunting rifle. We have built everything thus far around a dummy round that will seat the 215 Berger out a little bit further. (Thus the action is a long action instead of the short action you typically see for the 300 WSM).

I've seen some conflicting messages, but was wondering what everyone's thoughts are on reaming for this particular round that we have developed. Should the throat be lengthened from a typical WSM round? Or will a standard 300 WSM reamer work?

I'm already sold on the WSM...just want to see if I need to get a custom reamer purchased for this build.

 

[4xforfun]

You will be better served with a longer than normal throat. I just had a tube chambered up with a new reamer. The reamer (334 neck) was SUPPOSED to be throated so that the psi ring (base of the boat tail) was to be ABOVE the neck shoulder juncture. It isn't. I am going to check a bunch of things before I give the reamer maker a call...just in case. If you have a long action I see no reason why you would want the bullet in a space better used for gun powder!!

 

[TK50]

Was the reamer manufacture pacific tool and gauge?

 

[4xforfun]

Was the reamer manufacture pacific tool and gauge?

Yes....but.. Like I said...it could be something on our end not right. Also....the reamer was discussed over the phone only with me telling him what I was "looking for". No dummy round was sent. No throat numbers were discussed. Only that I wanted a .334 neck with the base of a 215 hybrid above the neck shoulder juncture. I am NOT QUALIFIED, and don't know the "language". It very well could have been a misunderstanding due to my inability to properly explain.

I don't even have the reamer or print....it is still at the gun smiths.

 

[azgutpile]

Saamii shows a .1884" free bore.

Last I spoke to PTG they recommended a .233" free bore for the 215 hybrid, which should place the start of the boattail sitting at the neck/ shoulder junction.

 

[awe2]

I just had one put together with .225 free bore. Sent my smith 2 dummy rounds and he cut it to match. I'm pretty sure he used a zero freebore reamer and a long throater to finish it out but I could be wrong about that. 2.410 ogive to case head. 2866 fps average with a sd of 6 out of a 28" Bartlien HV with 68gr H4831sc and CCI 200 primer. Don't know if any of this helps.