Need help with seating depth!!!

[Phantom Sniper]

Hi. I'm going to make this short and sweet. I have been reloading for a couple of years. I am working up test loads for my .308 win. I am using Varget and 175 SMK bullets. i am trying to get a seating depth of 2.825...just over saami to use in my rem 700 xcr lrt.

I have adjusted my rcbs seating dies and locked them in nice and tight. Upon seating my reloads, event though my dies are tight, I am seeing seating variance of +/- 0.005 of an inch. My dies are clean and rock solid on my press. I noticed that the tips of the smk's are not perfectly square which would effect my caliper reading. The rcbs dies use a cup (as you are aware) that cups the tip of the bullet and seats it this way.

I am wondering if I should leave these bullets the way that they have been seated or should I individually seat each one so that i have the same coal?

I am thinking that i should leave them as is because this way the bullets should all have the same distance to jump to the lands regardless of the coal. Can someone please advise me if i am wrong or right in this regard. Has anyone had the same problem with the smk's? What was your solution and result. Thanks

 

[john_1182]

Re: Need help with seating depth!!!

Could be one of several things.

1: Have you measured from the ogive instead of using a OAL for measurements. This would eliminate the variances in projectile lengths.
2: Is this a crushed load (projectile being loaded deep enough into the neck so that it is crushing/ pushing on the powder) you may be getting some spring back if you have a low neck tension.


Im sure there will be many others with more of a clue, i too haven't been reloading all that long.


Also welcome to the Hide.

 

[nova-birdman]

Re: Need help with seating depth!!!

I noticed similar variations, my solution (maybe I'm just OCD) waste always measure to Ogive, I use a micrometer seater so I seat like 0.005 long, then measure with a comparator, adjust, then final seat. It's an extra step, but doesn't add substantial time, and I'm assured all of them have the same jump, as precisely as I can measure

 

[john_1182]

Re: Need help with seating depth!!!

edited , wrong thread

 

[Fuzzball]

Re: Need help with seating depth!!!

"I am thinking that i should leave them as is because this way the bullets should all have the same distance to jump to the lands regardless of the coal."

You are thinking correctly.

 

[Phantom Sniper]

Re: Need help with seating depth!!!

Thanks guys. I really appreciate the advise. This was my first time loading the smk's. I have only loaded hunting rounds before.

Since the dies are locked in nice and tight, I will leave them as is. Will let you guys know how i made out later.

 

[vman]

Re: Need help with seating depth!!!

http://www.sinclairintl.com/.aspx/sid=64024/pid=36535/Product/HORNADY_LNL_COMPARATOR_BODY_W__14_INSE