bullet seating depth

[stxhunter]

If you take a particular load with a known OAL and move the bullet in or out say up to .050, will it significantly change the pressure or just slightly? Or does it mainly depend on powder type used? I am asking this question because I am using Westerns Powders published loading sheet for the 300 blackout round. It appears, and I verified this with Western, that the loads published were compressed loads. Not sure I am a fan of compressed loads or not because I am not familiar with them. I would like to try some other bullets they do not have listed is why I am asking the question about seating depth. Is it particuarly critical with compressed loads? Are non compressed loads more forgiving on seating depth? This may be a bunch of sillly questions its just that I'd rather be safer than sorry. Thanks for any advice!

[stimpylu32]

stx
 
I have run into problems before when trying to over-compress loads by seating the bullets deeper , with some powders they tend to not fire properly ( hang fire or not fire at all ) and other times the bullet will be pushed back out from the spring back of the powder itself and not chamber properly .
 
I have not seen any real pressure signs from this with my loads , however thats not to say it could not happen . Just remember that when you change either powder , brass , bullet or primer , you should drop back down and re-work up your loads , as any change will effect your pressure curve , just how much is hard to tell without a proper test , yet it will change that is for sure .
 
As for moving the bullet out , that should decrease the chamber pressure , yet even that is not a given , so whenever you change something , re-work the load . 
 
stimpy 

[stxhunter]

God advice Stimpy. That is something for me to go on. Thanks!