help with consistent seating depth ?

[Dgd6mm]

Do you have donuts, or do you not?
I have an inquiring mind.
Sorry if I missed it.
In the past when I had donuts form in my Lapua .243 brass after fire forming to 6mm Competition Match I used a inside neck reamer and cut them out.

 

[rebs]

Does trimming cases help with seating depth consistency

 

[TTE]

is there a way to get the donut out?

My turning mandrel has a cutting tip on it. Pretty sure it does not get all of the donut out, but at least some of it.

 

[6Creed73]

Does trimming cases help with seating depth consistency

Not really. It's possible that a longer neck has more friction when seating and the extra friction could affect the depth, but very minimally.

 

[Dave M.]

May I ask what full length dies you use to size your brass?

I’ve used many but now I have my gunsmith use my own sizing die reamer to make a custom die (not sure where the die blanks come from) and I use Short Action Customs bushings.
I still use Whidden full length bushing dies for two rifles and for another I’m using the Redding F/L bushing sizing die.
Dave

 

[Dave M.]

Not really. It's possible that a longer neck has more friction when seating and the extra friction could affect the depth, but very minimally.

A longer neck should have nothing to do with seating depth. An arbor press properly set up with a Wilson in line seating die (assuming the use of a quality bullet) will produce very accurate CBTO (easily +/-0.0015”). With Berger 180gr hybrids I can easily get CBTO of +/-0.0007”.
Dave

 

[6Creed73]

A longer neck should have nothing to do with seating depth. An arbor press properly set up with a Wilson in line seating die (assuming the use of a quality bullet) will produce very accurate CBTO (easily +/-0.0015”). With Berger 180gr hybrids I can easily get CBTO of +/-0.0007”.
Dave

I agree with you, that's why I said it shouldn't matter...the only thing I can think of where neck length could even remotely affect seating is due to added friction, but I've never experienced that.

I consistently get 0.0005 without an arbor press. Honestly, I would not be happy with 0.0015...I want it under a thousandths. I posted a video in this thread of me seating 5 and only 2 of them were 0.0005 off. People tend to not believe me when I say it, but its all about brass prep and good bullets. Consistent neck tension/pressure is key to consistent seating and how I get repeatable results.

 

[SubVet]

I am reloading for my Tikka 223 bolt gun using a Redding bushing die to size the case and neck. I am using an RCBS competition seating die to seat the bullets. I have-not been able to get consistent seating depth. I am loading Berger 80.5 full bore bullets and some 80 gr SMK's. The seating depth will vary by about .005 with both. I am only bumping the shoulder by .001 to .002. I have read that the Redding bushing die does not size the entire neck, could that be a problem ? Could another problem be the brass not being trimmed to the proper length ?
Is there anything you guys could suggest for me to be doing ?
I forgot to mention I am using Lapua once fired brass. Some have been fired 4 times and some 6 times

Since you are using a comparator and measuring base to ogive and getting 0.005” difference in BTO, a question? Are you using the same lot of bullets? Even the best bullets will vary with different lots.

 

[Dave M.]

I agree with you, that's why I said it shouldn't matter...the only thing I can think of where neck length could even remotely affect seating is due to added friction, but I've never experienced that.

I consistently get 0.0005 without an arbor press. Honestly, I would not be happy with 0.0015...I want it under a thousandths. I posted a video in this thread of me seating 5 and only 2 of them were 0.0005 off. People tend to not believe me when I say it, but its all about brass prep and good bullets. Consistent neck tension/pressure is key to consistent seating and how I get repeatable results.

The bullets make for consistent seating depth. Good bullets make the job easier, and sloppy bullets can cause all sorts of problems. One of the biggest mistakes I’ve seen is people trying to seat long VLD and hybrid style bullets using a standard seating stem and some of the bullet tips are actually touching the seating stem.
Dave

 

[jm22250]

I am reloading for my Tikka 223 bolt gun using a Redding bushing die to size the case and neck. I am using an RCBS competition seating die to seat the bullets. I have-not been able to get consistent seating depth. I am loading Berger 80.5 full bore bullets and some 80 gr SMK's. The seating depth will vary by about .005 with both. I am only bumping the shoulder by .001 to .002. I have read that the Redding bushing die does not size the entire neck, could that be a problem ? Could another problem be the brass not being trimmed to the proper length ?
Is there anything you guys could suggest for me to be doing ?
I forgot to mention I am using Lapua once fired brass. Some have been fired 4 times and some 6 times

My experience with the competion seating dies is mixed. The instructions tell you not to adjust the die to where it cams over. On my old rcbs rock chucker this works great. On my rcbs summit press it will leave me with up to 10 thous. variance. The summit needs to cam over to take the slack out of the system.

 

[BoydAllen]

My experience with the competion seating dies is mixed. The instructions tell you not to adjust the die to where it cams over. On my old rcbs rock chucker this works great. On my rcbs summit press it will leave me with up to 10 thous. variance. The summit needs to cam over to take the slack out of the system.

I think that this is the OP's answer, unless he is already setting up his die to toggle. I do not know about his die, but in the case of the Redding Competition seater, the reasons that they tell users not to have the die body in contact with the shell holder is because the die body is not hardened, and they are concerned that some ham fisted, if some is good, more is better customer would deform the die. Friends, who are not ham fisted dolts have improved the consistency of seating depth (ogive to case head) by setting up their dies to lightly toggle, with no damage to the die.