Free bore for a no neck turn 6PPC

[Brad Johnson]

What free bore would you go with with a no neck turned 6PPC reamer? Does anyone rent a such reamer?

 

[jackieschmidt]

.055.
If you are using Alpha or Fire Formed Lapua 220 Russian, a .273 neck is about right.
I think all of the major reamer grinders make a no turn 6PPC reamer.

 

[Brad Johnson]

Thanks

 

[Mulligan]

if you go with a no turn the effective freebore on a 0 FB reamer is about .015-.
016"
That taper from a thick neck to the FB adds up......... ask me how I know.
Just something to consider

CW

Edit to add visual of what I call effective freebore.....

 

[coldboreshot]

As I progressively learn about the PPC's, would not the freebore depend on the bullet profile and not so much the chamber neck diameter? Turned vs no turn?
Please explain.

 

[ShtrRdy]

I'm still learning these fine points, but as @Mulligan pointed out, if you have a larger diameter chamber neck then the length of the leade is a longer distance to get to the top of the lands.

 

[coldboreshot]

Ah. Got it.

 

[Shooter13]

Thanks

I have one, .045 FB and with the aforementioned from @Muligan it works out to about .055 to .060, I use Barts Avengers (boattails) and don't want more than that.

 

[Mulligan]

With the one I have (the print above), it works well with 68 grain bt bullets and most any flatbase bullet of the same weight. With a little bit of throat erosion, jamming 65 gr boattails is a delicate balance.
CW

 

[Jud96]

It depends on the overall length, freebore diameter, and leade angle. My first PPC reamer I messed up and ordered a .050FB with 1.5 degree leade but .244FB diameter and 1.525” length. I ended up having too much “effective” fullbore as @Mulligan described it. My fireformed brass was about 1.500” so there was .025 and the freebore diameter was more like .2445 so those two things alone added a decent amount of effective freebore.

All this to say, I’d recommend .025-.050FB, .2437-.244FB diameter, and 1.510” chamber length. For neck diameter I’d do .273-.274. The boattail bullets we shoot today have very short bearing surfaces.

 

[jackieschmidt]

My reamer is a .269 neck with a .050 Freebore and works great with just about any 68 grn bullet made on a .825 jacket.

The bullet I make is a double ogive BT.