22 ppc free bore

[Mike Montgomery]

What is the recommended free bore dimension for a 22 ppc shooting 40 to 52 grain bullets?
Thanks in advance for any and all responses,

Mike Montgomery

 

[DaveTooley]

.040" for 52's

 

[Mike Montgomery]

Thanks for the reply Dave! Would that dimension allow me to shoot both 40 and 52 grain bullets?

 

[DaveTooley]

Allowing for a shorter than chamber length neck, the transition from the neck to the FB and the distance from the FB to contact with the bore I believe it will. Just rough numbers 15+14+40+15=roughly .084" of exposed bearing surface.
From Berger's website for the 40 gr. bullet.

Bearing Surface	0.194

 

[Mike Montgomery]

Thanks again for the reply! I made a cut in a piece of brass with a dremmel tool and took some measurements with a 52 and a 40 grain bullet seated to the neck/shoulder junction. Your assessment is not far off. Thanks for the help with this.

Mike