Neck clearance calculator

[OmegaRed]

Through my recent quest for more knowledge, some forum members explained the very simple variables to be able to determine safe neck clearance. Hopefully it may help someone.

Here is my contribution to the forum that may help simplify this for a new reloader, that I made for myself in an excel sheet. You can copy and paste the formula into an excel sheet to easily punch in your input numbers, and it will give you neck clearance and your maximum loaded round neck diameter.

Don't type in the "neck clearance" and "maximum loaded round neck diameter" B columns. These are the calculations. Your only input boxes are the "neck chamber", "neck thickness", "bullet diameter".

FORMULAS (copy and paste this into the A1 cell):

Calculator:

Neck Clearance =SUM(B6-(B7*2)-B8)
Maximum Loaded Round Neck Diameter =SUM(B6-B3)

Neck Chamber 0.27
Neck thickness (x2) 0.013
Bullet Diameter 0.243

 

[mikecr]

you attached the file as a .jpg which is unusable to anyone.
'Neck Thickness' entry is simply that (not x2)
Honestly, anyone should be able to do this stuff in their head. But it's nice of you to help others like this.

 

[XBBR Shooter]

I once ran a 0.001" neck clearance neck in a bench rifle - it was "safe", but a nightmare to shoot and live with !!

2.5 to 3 thou is a reccommended total neck clearance for bench rifles.

Take chamber neck diameter, and minus 0.0025"

Take result and subtract bullet diameter (to 3 places - 0.XXX).

Divide result by 2, and that is your MAXIMUM neck wall thickness...

As Mikecr said, you can do it in your head (or on you fingers )

 

[OmegaRed]

you attached the file as a .jpg which is unusable to anyone.
'Neck Thickness' entry is simply that (not x2)
Honestly, anyone should be able to do this stuff in their head. But it's nice of you to help others like this.

Hence the reason I included the formula's in the body

 

[OmegaRed]

I once ran a 0.001" neck clearance neck in a bench rifle - it was "safe", but a nightmare to shoot and live with !!

2.5 to 3 thou is a reccommended total neck clearance for bench rifles.

Take chamber neck diameter, and minus 0.0025"

Take result and subtract bullet diameter (to 3 places - 0.XXX).

Divide result by 2, and that is your MAXIMUM neck wall thickness...

As Mikecr said, you can do it in your head (or on you fingers )

Noted, thanks.