300 Norma Magnum Improved reamer and die release

[Alex Wheeler]

I have released my reamer design to the public. Bullet Central will be selling the sizing dies again soon. This one is set up for a crush fit on new Lapua brass and is a compromise for the 230/245 Berger.

 

[Earnhardt]

Alex, what is your COAL with the 245's seated for this reamer spec?
Thanks

 

[Jordan Funk]

I have released my reamer design to the public. Bullet Central will be selling the sizing dies again soon. This one is set up for a crush fit on new Lapua brass and is a compromise for the 230/245 Berger.View attachment 322794

Is this reamer available for rent anywhere that you know of? Thx.

 

[Mad Minion]

Very similar to my reamer design. Great minds think alike! the biggest difference is the freebore on mine is .286 and seats the 245 Bergers OAL at 3.77

 

[Earnhardt]

Free bore on Wheeler's is .275"?

 

[Mad Minion]

Free bore on Wheeler's is .275"?

Correct

 

[nksmfamjp]

I'm just wondering…why not use a 40 deg shoulder?

 

[Mad Minion]

I'm just wondering…why not use a 40 deg shoulder?

For me it was simple, I wanted to keep the bullet out of the powder column. A 40 deg shoulder wouldn't give me the amount of neck to bearing surface for bullet tension, I use this round to hunt with. I didn't want to have to baby these rounds in the woods and it gives me room for throat erosion.

 

[nksmfamjp]

Does shoulder angle affect neck tension?

 

[Mad Minion]

Does shoulder angle affect neck tension?

No, but with a sharp shoulder you would have to seat the bullet out farther into the neck to accomplish the goal of seating out of the powder column. The 245 berger has a fairly long boat tail.

 

[nksmfamjp]

No, but with a sharp shoulder you would have to seat the bullet out farther into the neck to accomplish the goal of seating out of the powder column. The 245 berger has a fairly long boat tail.

So, I think I hear you saying you want the boat tail base at or above the body to shoulder junction. So, given that, there would be less bearing surface engagement in the neck because the boat tail is so long. I think I understand that point.

Why is this important?

 

[Mad Minion]

So, I think I hear you saying you want the boat tail base at or above the body to shoulder junction. So, given that, there would be less bearing surface engagement in the neck because the boat tail is so long. I think I understand that point.

Why is this important

So, I think I hear you saying you want the boat tail base at or above the body to shoulder junction. So, given that, there would be less bearing surface engagement in the neck because the boat tail is so long. I think I understand that point.

Why is this important?

You tell me

 

[E4aker]

Changing the shoulder angle from 35 to 40 is not changing the bullet bearing surface in the neck….some bad info here.

Different freebore lengths will affect it but not shoulder angle.

 

[Mad Minion]

Changing the shoulder angle from 35 to 40 is not changing the bullet bearing surface in the neck….some bad info here.

Different freebore lengths will affect it but not shoulder angle.

How is it bad info? The shoulder is sharper. The distance from shoulder and case body to shoulder neck junction decreases. The whole goal, for me, was to keep the bullet out of the powder column. To do that the bullet moves further into the neck with 40 deg shoulder. Doing this decreases the amount of bearing surface left in the neck.
.286 is the longest freebore I could get and still keep the round in a magazine, a 40 degree shoulder would force me to single feed, I dont want to do that.