Seating length?

bdh308

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I bought some used competition Rcbs dies for 308win. Ive only been reloading for about 6mths so bare with me if this dumb question. I cant seem to get the bullet seated accurately everytime. Im seating the bullet to 2.820 but Ill get some that are 2.821 or 2.19.5 sometimes 2.17. This really pisses me off that I cant get them all the same. Is this something that everyone experiences?Im useing a Lee press and Im trimming all my brass to 2.08.
 

FIREMEDIC27

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Re: Seating length?

If you are measuring overall length, you are probably getting inconsistant bullet lengths. Measure a few bullets, base to tip and you will catch my drift. If you get a bullet comparator from Sinclair, this will probably fix the seating length differences. It will alow you to measure the ogive to case head. When you start measuring this, you will get the consistancy you are looking for.

http://www.sinclairintl.com/product/5581/Bullet-Comparators
 

bdh308

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Re: Seating length?

Duhhhhh...I told u it was a dumb ?. I never even thought of measuring the bullet especially ballistic tips like an Amax.
 

desertrat1979

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Re: Seating length?

I had slight variations when I was using Sierra MKs. I have yet to get a box of AMAXs that have as much a diffrence. The tips have always been pretty consistent. I never used the RCBS dies, but does it have a way to lock it into position. Also, since they are a used set make sure they are clean internally. Maybe there is something getting in the way.
 

superde

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Re: Seating length?

Difference in the shape/lengths of the bullets (as mentioned by FIREMEDIC27 above). I use Redding competition seating dies and back the seating depth off .005 in between each round. After the initial seating, I measure with a Hornady bullet comparator, which measures off the ogive. Then I adjust the seating depth down as necessary to make them as close as possible to the same length.
 

Fuzzball

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Re: Seating length?

" Ill get some that are 2.821 or 2.19.5 sometimes 2.17. This really pisses me off that I cant get them all the same."

In the real world, that is exactly the same.

Even if all else is perfect, you can cause some such variations with how you work the press during seating.
 

GLShooter

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Re: Seating length?

Individual bullets vary from bullet to bullet and lotto lot on OAL. The ogive measurement is most important in accuracy as it will determine the jump to the lands.

Greg L.
 

bdh308

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Re: Seating length?

Ive checked the die itself and its fine. Measured the Amax's and there are a few that have variances but not many but some can be up to .002 or .003 off. From now on Ill just check the measurements of the bullet first and seat off of that. Thanks guys for your wisdom.