Flat Spot Method Step Charges

[hunter24605]

Is there a rule of thumb for determining the step size when doing a flat spot test? 1% max charge? (i.e. 60 grain max charge 1% = .6 grain increments) Can you have too small of increments where the flat spot may be hard to decipher?..I'm going from 28 grain start to 30 grain max and thinking about using .2 grain increments..Is that about where I need to be?
Thx

 

[Dwh7271]

Yessir, that should be perfect.
If you're going to load "Fotis cartridges :lol: " then .5 might be better.

 

[hunter24605]

Yessir, that should be perfect.
If you're going to load "Fotis cartridges :lol: " then .5 might be better.

Thanks! Just what I wanted to hear....:lol: I'm also guilty of owning a few shoulder fired artillery cartridges..

 

[Dwh7271]

Just kidding Fotis!

 

[SJB358]

Is there a rule of thumb for determining the step size when doing a flat spot test? 1% max charge? (i.e. 60 grain max charge 1% = .6 grain increments) Can you have too small of increments where the flat spot may be hard to decipher?..I'm going from 28 grain start to 30 grain max and thinking about using .2 grain increments..Is that about where I need to be?
Thx

On the smaller cartridges I’ve used .1 and it really showed me the spots but like Dewey said .2 has worked well in the 06 based stuff up to Win Mag sorta capacity.

 

[truck driver]

The .2 works well in the 7RM and 338Win size cases also which are the largest I have tried it in.

 

[hunter24605]

Is there a rule of thumb for determining the step size when doing a flat spot test? 1% max charge? (i.e. 60 grain max charge 1% = .6 grain increments) Can you have too small of increments where the flat spot may be hard to decipher?..I'm going from 28 grain start to 30 grain max and thinking about using .2 grain increments..Is that about where I need to be?
Thx

On the smaller cartridges I’ve used .1 and it really showed me the spots but like Dewey said .2 has worked well in the 06 based stuff up to Win Mag sorta capacity.

Ok...Good to know because I just assumed that the small increments would just show a steady, albeit slight, increase in velocity making the flat spot hard to decipher...But, you know what they say about when you assume
:lol:

Guess for the 223 Rem, 204 Ruger, etc. I'll go with .1