Chambering question for 7mag

[MOOSE39465]

What chamber dimensions would you guys recommend when building a 7mag? I am not sure how much free bore is needed when using 160 to 180 grain bullets?

 

[FearNoWind]

... I am not sure how much free bore is needed when using 160 to 180 grain bullets?

The 7mm Mag may very well have more variations in chamber dimensions than any other rifle I've ever been exposed to.
SAMMI specs will provide what's needed.
But, IMO, if you're building a custom rifle the free bore you'll need is dependant largely on what you want to load for it using those 160 - 180 grain bullets .

 

[dok7mm]

I'm running 162 eld-x, 168 & 180 Bergers with a .140" freebore. I shoot mostly the 168s in the 7 mag and 180s in my STW. If you don't get a Smith to advise you, I'll try to find my reamer print. Bolt face to lands is +/- 2.771" with a 180 in mine.

 

[philipbrousseau]

you might be able to take a case and seat the bullet you want to use at the seating depth you wont and have your smith throat the rifle for .010 off your bullet.

 

[J E Custom]

personally, I recommend using SAMME specifications/chamber reamers and adjust the bullet for best Performance.

Building a rifle around a bullet can be risky, It the barrel doesn't like the bullet your done.

SAMME spec. chambers are designed to work well with most all bullets as long as they are loaded properly and within SAMME spec.

I used a SAMME spec. 7 RM for 1000 yard matches and shot 168 SMKs with great success, and loaded to extreme accuracy with ease. so don't over think the chamber dimensions and you will be ok.

Just My Opinion

J E CUSTOM