Consistent bullet seating depth into a compressed load

[Boomer79]

When I seat a bullet into a compress load with my Redding competition microseater the seating depth is not consistent when measured with a bullet comparator. Bullet to bullet may be 15 thousands difference. Should I wait 24 hrs or more and then seat with the same setting on the microseater or adjust the settings and immediately seat the bullet again ? What technique will give me better consistency?

 

[ar10ar15man]

increase neck tension
settle the powder by holding case on vib brass tumbler

number one...get a new load.

redding has said more than once that the seater is not built for continuous compression..it will bell the seater.....

 

[tenring]

Yes, decrease the load. Powder is forcing the bullet upward, and OAL will be inconsistent. Alternatively, you can try using a very long funnel, and slowly sifting the powder as it decends. That may work, depending on how tight you wanna cram the powder in the case.

 

[Boomer79]

Thanks I will try both recommendations.

 

[BigDMT]

Are you measuring to bullet ogive or tip? You mentioned a comparator so I assume ogive, but just in case;

If measuring to tip, don't forget that OAL can vary a good bit when measuring to the tip because bullets always vary in that department. Measurement from case base to bullet ogive should be your focus before coming to conclusions.

OAL is really only a concern for fitting in a magazine, not really meant for determining consistent seating depth

Also agree to avoid compressed loads. If a load is compressed with enough pressure, it can also change case body width and headspacing from the pressure when the bullet is seated.

 

[searcher]

I'd reduce load to next accuracy node down or change powder. If you drop powder down tube to increase fill, you may not get consistency due to the high level of fill you now have. If you increase tension on the neck, aside from what has already been pointed out, you will have to add much more tension than what is usually conducive to good accuracy. Otherwise, you will have to shoot ammo and not store for long as the necks will relax over time and bullets will be pushed back out somewhat. I've been there. Might also try (if small primer) backing off charge a few grains and substituting a magnum primer and working back up the load and see if you can get on a node before the problem develops again. A magnum primer usually equates to ROUGHLY 1/2 grain of powder to come up with equivalent velocity in my PPC/6BR loads. Haven't tried this with large primers so don't know what the power difference would be.

 

[Nomad47]

"A magnum primer usually equates to ROUGHLY 1/2 grain of powder to come up with equivalent velocity in my PPC/6BR loads. Haven't tried this with large primers so don't know what the power difference would be."

It's pretty much the same with large rifle primers.

 

[dboyles]

If you're not already, look at using a drop tube when pouring your powder. Also, be careful with the Redding seaters on compressed loads - I've cracked a stem before (tough to see), and I know I'm not the only one.