Anyone have a 358 Norma with CIP chamber dimensions? How does it shoot? Does the throat seem short? I am having one built and we are currently discussing the reamer options.

The CIP chamber has a throat that is shaped like a cone. Starts out at .3598” then tapers to bore diameter over .240”. It seems like it would be short and .3598” seems like quite a “loose” start for the bullet, but curious if anyone out there has any experience with it. Here is a link to the CIP dimensions: http://www.cip-bobp.org/homolo...iiical-en-page26.pdf

Seems like most modern chambers have parallel sided freebore and then a cone shaped throat.

Thoughts or recommendations?

I do not have a drawing to share with you but I have owned several 358 Normas and I have friends that have or have had 358 Normas. I don't believe 2 of them had the same throat. The shortest I've seen is in a Husqvarna 1600 that I own right now. Had one built on a P-14 action with a long throat and the max load in that rifle was 3 grs more than the 1600. I also had a M98 that had a throat somewhere in the middle. Not sure if that helps.

SAAMI specs are too short for me on my 358 Norma build. Measuring some different rounds right now and then will lengthen throat based on this.

I did the same on my 35 Whelen. SAAMI specs were short. Optimized for a 225 gr TSX at 3.320" at .030" off the lands.

quote:

Originally posted by Austin Hunter:
SAAMI specs are too short for me on my 358 Norma build. Measuring some different rounds right now and then will lengthen throat based on this.

I did the same on my 35 Whelen. SAAMI specs were short. Optimized for a 225 gr TSX at 3.320" at .030" off the lands.

Well, I finally made my OAL gauge tonight and measured the following bullets:

225 gr TSX
250 gr Northfork
250 gr Partition
250 gr Oryx
275 gr Woodleigh
275 gr Northfork

The SAAMI specs work for all the bullets except the Northforks. I would have to length the throat .015-.020" depending on the gr to be .010" off the lands at the very top of the pressure bands.

The other bullets have plenty off room off the lands. I target .010" for standard bullets, .030" for solids/Barnes. I'd have to seat the TSX deeper than I normally do, but it would work.

So, going to start my load development now and try to get a good 250 gr Oryx load.

Starting with RL16.

Excellent info, that helps me out. I’m wondering how a 280gr A-frame would measure up?

I’ll be interested to know your velocities and accuracy you get during load development if you don’t mind sharing.

quote:

Originally posted by +Templar+:
Excellent info, that helps me out. I’m wondering how a 280gr A-frame would measure up?

I’ll be interested to know your velocities and accuracy you get during load development if you don’t mind sharing.

will do. I have a 26" Barrel.