6bra Necks Looser than other

[6MMsteve]

do you keep your FL die clean, expander clean, clean dies make better brass

 

[Ranger188]

You said you have 3 bra's.
Are you using the same brass in all 3?
What brass are you using?
How many firings?

 

[MDT6BRA]

My die was pretty dirty so I cleaned it to make sure that wasn’t the problem and it did the same thing. I keep the brass separate but they were all cut with same reamer and brass measures exactly the same with the Whidden shoulder comparator

 

[swd]

If you start annealing not only will sizing get a lot more consistent but the brass will last even longer. That’s exactly why we anneal.

 

[JFrank]

If you have the expander ball intact, perhaps your brass is just getting thinned out from the rolling pin on pie dough effect of that style die.

 

[4xforfun]

I have measured the necks after sizing and they all measure .240 but some of the bullets seat with much less effort on the ram and in return the looser necks are measuring up to about 10thou short oal (ogive). What is going on?

".240"???? Is that the inside measurment of the neck?

 

[Mike Montgomery]

How many firings do you have on your brass? I believe that your brass is work hardening and you will need to anneal it to have consistent neck tension. Going to a smaller bushing will work for awhile but won't likely give consistent neck tension. Don't throw it away, just anneal it.

 

[MDT6BRA]

Yes sir my brass measures 240 inside and then 243 after firing. That doesn’t seem odd to me, it being a 6mm

 

[4xforfun]

Yes sir my brass measures 240 inside and then 243 after firing. That doesn’t seem odd to me, it being a 6mm

Nope....not at all. BUT.......it seems like a strange way to measure. The problems you are bringing up could very well be caused by to tight of OUTSIDE diameter....... Are you using a standard die with an expander button or a bushing die with the expander removed?

 

[Geronimo Jim]

I always anneal and trim every firing.

 

[Mike Montgomery]

I feel the need to add an additional comment; if you can't insert a bullet in a fired case then you either have a donut or the necks are too thick for your chamber creating not enough neck clearance which can cause pressure and accuracy issues.

 

[MDT6BRA]

It’s a standard Whidden non bushing die with a expander and sizes great but when you seat the bullet some are a lot looser than others, you can tell it by the handle of the press and the oal (ogive) will be shorter

 

[Ccrider]

Remember seating feel can be significantly effected by the amount of carbon/lube in the neck.

 

[Gargoyle]

Remember seating feel can be significantly effected by the amount of carbon/lube in the neck.

You beat me to it!
I use a q-tip with alcohol to wipe out the necks, then I add a small film of imperial sizing wax on the bullet base, like a micron thick amount. Smooth operator!

 

[Gargoyle]

I am reloading 90gr eldx in a 10twist hart. I am noticing some of my bullets seat a lot easier than others. I have measured the necks after sizing and they all measure .240 but some of the bullets seat with much less effort on the ram and in return the looser necks are measuring up to about 10thou short oal (ogive). What is going on?

6bra Eldx oal varying when seating

The other day I was loading some 90gr eldx for my 6bra and my oal length from base to ogive was pretty much exactly the same from shell to shell. Today I am getting lengths varying up to 5 thou. Any ideas? Whidden dies, lapua brass

forum.accurateshooter.com

Deja Vu...

 

[fkimble@charter.net]

Have you mearured the OD of your bullets? Perhaps your bullets have a few undersized mixed in. Wouldn't be he first time.

Frank

 

[Webster]

It's a good indication the neck tension is random. When this occurs the length will vary because of the pressure being applied on each bullet at seating is different and will therefore having a different stopping point. Swapping over to a smaller bushing to gain neck tension may help.

Added later:

OAL VARIATION
The bullet ogive can contact the entrance radius then slide until it grips the bullet firmly. Neck tension should determine how far the bullet enters the stem before there is no sliding and there is a no slip grip on the bullet. No different than adjusting the micrometer head a few thou. Does anyone agree this may cause variation in OAL? Every ogive may not be the same if you are measuring ogive dimensions to a 10 thou. May be several factors contributing to OAL variation.



Wilson standard straight line micrometer seater stem tip. They also make a a VLD stem tip. Doesn’t look like I thought it would. Looks like a simple tube cut off straight then a radius put on the edge.

 

[Mike Montgomery]

I don’t have anneal machine or ever done it. Does it make sense to have all the same measurements and just some of the cases not as tight on the bullet anymore?

Even brass with the same number of firings doesn't work harden at the same rate. I believe this is what is causing your inconsistent seating depths.

 

[Dave M.]

I'm pretty sure that it's annealing that you need.

Send your brass off to have them annealed
Dave

 

[Webster]

Even brass with the same number of firings doesn't work harden at the same rate. I believe this is what is causing your inconsistent seating depths.

Don't understand how neck work hardening would affect OAL. If you assume the bullet seating stem tip slippage isn't involved. Your die is set to a certain fixed position, the case is pushed a fixed amount into the seater based on how you adjusted the die. When you pull the press handle all the way down there should be no variation on how far the bullet is pushed in. The leverage of the press will overcome any variation in neck tension. Are you measuring base to ogive or base to tip? The tip closure looks different on almost all bullets.