Improved version reamer dimension

[300SALRH]

Gents, some guidance please with regards to improved version reamer dimension and especially the base to shoulder length.

When fire forming, some suggest creating a false shoulder, while others suggest jamming the bullet and some suggest using normal loads as long as chamber allows primer ignition. I assume a snuck fit is better.

Been comparing some reamer prints. With regards to the base to shoulder length, some clearly follow the minimum CIP or SAAMI length while a small amount uses a shorter length.

My question, do you use die SAAMI or CIP minimum length or can one go a little shorter? If yes, how much? I assume if you have custom dies made for the wild cat, you will be able to bump the shoulder back until you have snuck fit? Will this only be applicable for all shoulder angels? I’m aware that too much bump of the shoulder could potentially result in doughnuts. Am I missing something and any disadvantages of having a shorter base to shoulder length?

 

[Grimstod]

What cartridge?

 

[300SALRH]

300 NM

 

[Geno C]

I have all of my AI type chambers set .007" short of zero headspace of the parent round. Some virgin brass is tight going in but I have yet to stretch a case since I started doing this. Lube on the lugs and light oil on the bolt face keep the tight ones from galling anything. There are guys that go longer and ones that go shorter. This is just what works for me

 

[Shynloco]

Gents, some guidance please with regards to improved version reamer dimension and especially the base to shoulder length.

When fire forming, some suggest creating a false shoulder, while others suggest jamming the bullet and some suggest using normal loads as long as chamber allows primer ignition. I assume a snuck fit is better.

Been comparing some reamer prints. With regards to the base to shoulder length, some clearly follow the minimum CIP or SAAMI length while a small amount uses a shorter length.

My question, do you use die SAAMI or CIP minimum length or can one go a little shorter? If yes, how much? I assume if you have custom dies made for the wild cat, you will be able to bump the shoulder back until you have snuck fit? Will this only be applicable for all shoulder angels? I’m aware that too much bump of the shoulder could potentially result in doughnuts. Am I missing something and any disadvantages of having a shorter base to shoulder length?

After reading your question, if I were you, I would call Dave Kiff at Pacific Tool and Gauge and talk to him about the specifics of what you are trying to accomplish. Whenever I have a new rig built and I am going to use a specific bullet, Dave has been very helpful in suggesting and supplying the exact reamer I need to get me to where I want to go. And to be more specific, the freebase used for the chamber may include or exclude bullets of a certain length even when of the same caliber. Depends again on EXACTLY what you want to accomplish. SAMMI specs on the other hand, are more inclusive to a wider range in length of bullets you can use in a specific chamber/caliber.

Alex

 

[Grimstod]

Dave Kiff is very helpful and helped me a lot to on one of my more difficult wildcats. The wait time to get a reamer from there though is long. Just a warning.

 

[Tommie]

The 300 Norma headspaces at the belt so (at least technically) creating a false shoulder would be unnecessary.

That said, I’ve heard it said that belt dimensions can vary and are supposedly unreliable. Fact or urban legend: unknown to me.