Seating Depth

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Nov 6, 2022
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Im running a mid range powder charge with a seating depth that provides groups of less than a half inch. Will the same seating depth hold true as I increase powder to increase the speed.
 
OP
S
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Nov 6, 2022
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I have a 7ss and was just fire forming the brass with mild and got several groups half inch or less. I was hoping it would hold true to the powder increase
 

Rich M

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One way to find out.

There have been a couple posts and it is usually about the jump to the lands. Other posts talk about picking your velocity and then adjusting the seating to get the best group.
 

EdP

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I know some that swear by finding seating depth first before charge weight
That's how I do it. If you find a velocity node that works well first and then play with seating depth the velocity is going to change as seating depth is changed, so I don't understand tweaking velocity first, but a lot of folks do it that way. Others on here have other methods that are worth a look too. I think your best bet is to try other charges with that same seating depth and see what happens.
 
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Harvey_NW

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In my experience it can, but it depends on if you're trying to find an OCW or ride the edge of pressure and get the absolute most speed possible. An OCW or seating depth test will tell you.
 
OP
S
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Thank you for all the replies. Guess I will just increase the powder charge and see how it works out.
 
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Unless you’re looking for 150 fps or more, speed changes aren’t that significant.

Run your existing load through a ballistics program and notice the velocity at distance.

Run the load with the velocity you’re trying for through the same program, and compare the two.

Unless your existing load is really slow or your ideal load is really hot, I don’t expect you’ll see much difference in performance.




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