What the heck have I done???

[Mad Professor]

I've been working on setting the seating and crimp die and I feel like I'm chasing my tail. I'm shooting for the specified 1.125 and they're coming out 1.123-1.133 without adjusting anything. Is that good enough? All drop right into the gauge but I cant seem to get it to be smack on 1.125 or at least the same across a group of 5.

Bullet quality and consistency will have a big bearing on the range they seat at. You are not seating the bullet at the tip, but are measuring at the tip. When using cast, plated, and coated bullets, you will greater deviations that when using most jacketed bullets.

You can sometimes change or modify the seating die to get better consistency.

The other thing I have seen is the bullet pushing back forward before crimp with compressed loads. It will vary because of neck tension.

 

[adamsredlines]

I flipped the seat die to the flat tip side and this batch is 115gr Montana Gold JHP which I would consider flat tip even though they are HP. Should I be using the other side of the seating die for RN stuff?

http://montanagoldbullet.com/9mm-115gr-jhp-4-000ct-case/

 

[Mad Professor]

I flipped the seat die to the flat tip side and this batch is 115gr Montana Gold JHP which I would consider flat tip even though they are HP. Should I be using the other side of the seating die for RN stuff?

http://montanagoldbullet.com/9mm-115gr-jhp-4-000ct-case/

I use the rounded seat inserts with the JHPs unless I find the radius is so much different it mars the bullet. That is rare, but I seat and crimp in different stages. Seating and crimping in the same stage may increase the tendency to do that.

My COLs are almost always with .005”. Usually with in .003”.

 

[adamsredlines]

I'll flip it and see. I am not sure what is acceptable variance but it SEEMS it should be closer than what I'm getting. I guess its not too bad if you consider its -.002/+.008

 

[Dumpstick]

Grab a box of factory rounds some time, and spend a while measuring OAL. It will set your mind to rest.

 

[Mad Professor]

Grab a box of factory rounds some time, and spend a while measuring OAL. It will set your mind to rest.

Running some over a chrono will scare you.

 

[Glock 40]

Edit - well I responded not seeing there was another page of responses...

What bullets are you using? Do you have the seating die set for that type of bullet? IE RN or WC? Is the shell plate adjusted properly 10 minutes into this video.

A quick look at 4 different types of ammo off my 550 are usually are within +/-.002 with majority within +/- .0005 the .01 you are seeing seems like a pretty big swing. I would imagine they will run without issue but I would think they should be more consistent. If I want 1.125 and I land at 1.124 I just go with it. You can spend a lot of time trying for that perfect number. Also you want to get in a rhythm when running the machine so your pressing down the same each time and its nice and smooth.

If you take the longer bullets and run them through the seater again do they change or stay the same?

 

[adamsredlines]

I flipped/reset the seating die and reset the crimp and am now getting 1.120-1.126 with a 5 round run.
I'll measure a few between seat and crimp and see if it changes.

 

[thor447]

I am glad to see your finally able to start using your press. It seems you've been waiting on various parts for quite some time now. Enjoy the process, I know I certainly am. I did a small amount of shooting yesterday, got home, and decided I liked my most recent loads so much that I made another 350 of them for my next range trip! I love this Dillon!

 

[Glock 40]

Also are your die lock nuts tight? You don't have to kill them but if you don't get them very tight they can loosen up. When I get a tool head where I like it I will make a small sharpie mark on the die and lock nut so I can quickly see if anything have moved when I sit down to load.