Load Development / Reloading Question

[Russ-T]

Hey Guys!

I'm doing some load development for a great little 243 my dad gave me.

I've been working on 108gr Berger Elite Hunter and MAGPRO.

When seating bullets, I found there to be quite a bit of variance on COAL & CBTO with the same seating die setting.

Question:

Should I change the Seating Die setting to make every cartridge measure the same?
Tried this with marginal/sporadic accuracy.

or

Get a setting and stick with it for the number of cartridges in the group?
How do you get an accurate measurement for repeatability?

Thanks for any input.

 

[D_Max]

Watch out for keyholing some older 243 win had a vey slow rate of twist

 

[Russ-T]

Watch out for keyholing some older 243 win had a vey slow rate of twist

interestingly, the Berger 108s stabilize, but the Barnes 95gr LRX keyhole...

 

[rbstern]

CBTO variance is usually a case length problem, or poorly uniformed bullet construction.

COAL variance shouldn't happen (at least not more than .001"), unless your press/die is malfunctioning in some way, or you are putting pressure on the tip of the bullet with something like chambering gage, or testing the ammo feed in the rifle.

Tell us more about your setup and process.

 

[D_Max]

interestingly, the Berger 108s stabilize, but the Barnes 95gr LRX keyhole...

The Berger might at a longer distance

 

[TrueGrit]

Get a good competition seating die and clean everything good with brake clean. You can load long, measure, adjust die down and reseat. Measure a box of factory ammo and you'll be surprised how much variation there is. The key to making good ammo is everything has to be exactly the same every time.

 

[greg vess]

I'm sure there are better dies out there but I use a Hornady competition seating die that has the little adjustable micrometer on top. Once I set the seating depth they all come out the same every single time. I also trim the cases with a Lee case trimmer that trims the cases exactly the same every single time. It's probably not the best to use and a bit rudimentary but it gives me good consistent depth settings. Also the trimmer gives me the same case length every single time as well. It's good enough to give me half MOA accuracy out of some of my rifles with amazing consistency. I just take my time and measure each case and finished cartridge on every one I plan on shooting for accuracy.
Admittedly I'm no reloading pro but with what I do load I seem to get good consistent results. Slow going and consistent checks on every cartridge seems to work for me anyway. I have only been reloading for 10 years so I am sure there are a many more members that can add easier and better results. I just like to use some dies better than others due to ease and end result.

 

[BHPSteel]

How consistent are the neck dimensions on the brass?

 

[Russ-T]

CBTO variance is usually a case length problem, or poorly uniformed bullet construction.

COAL variance shouldn't happen (at least not more than .001"), unless your press/die is malfunctioning in some way, or you are putting pressure on the tip of the bullet with something like chambering gage, or testing the ammo feed in the rifle.

Tell us more about your setup and process.

Using redding dies on a rock chucker.

Brass was resized and trimmed consistently

Berger Bullets

Basic Lyman Dial Calipers with hornady comparitor

What was weird about this particular loading was that I was getting drastically different COAL and CBTO measurements from one cartridge after another. up to .008

I may break it all down and brake clean the dies, but this was more dramatic than I've seen in the past.

 

[Russ-T]

How consistent are the neck dimensions on the brass?

Never measured before. I've only used the case length and assumed a small shoulder bump .002