Testing Cases After Resizing?

[jimbires]

I've wondered about the once fired brass not being fully expanded to chamber size and how that affects bumping. I have only once fired brass after saving brass for quite awhile waiting to start reloading. The person that gave me a reloading lesson likes FL sizing and that's what I purchased in 5 calibers. My question is should once fired brass that chambers in my rifles NOT be FL sized until it no longer chambers?

I like to shoot brass until it gets a little tight to chamber . you'll be able to tell it's obvious . then I set up my full length die to bump my shoulder back about .002" . I have a lot of neck sizing dies that I use until my brass gets tight . you should be able to set up the full length die good enough to size the neck only . make firm contact then raise the die away from the shellholder 1 full turn . this will size most of the neck and not touch the body . a die is threaded 7/8-14 meaning 14 threads per inch . we divide one inch by 14 threads gives us about .071" per one turn of the die . .071" should be plenty of clearance to not touch the body of the case , and size the neck well enough even on short neck cases . I usually take 4 or 5 pieces of brass and shoot them over and over until they get tight , then get to work set up my full length die . after I get the die set up , I'll size all the brass in it fully expanded or not . the smaller brass catches up . the reason for using 4 or 5 pieces of brass is , if I size to much that piece of brass needs fired again before it's useful , so I get a few extra from the start . it also seems like sneaking up on the preferred setting gives a slightly different result than when sizing in one stroke , so a fine tuning on another piece of brass may be needed until perfect .

 

[Rich Coyle]

I have full length dies only for my wildcats. So they get used from the first time to the last time the brass is used.

 

[General RE LEE]

Erik Cortina says always full length resize lol.

 

[ButterBean]

I have full length dies only for my wildcats. So they get used from the first time to the last time the brass is used.

I'm sure knowing that that helped the OP out tremendously

 

[Rich Coyle]

I'm sure knowing that that helped the OP out tremendously

I hope so. Some of these folks take themselves and life way to seriously.

 

[ButterBean]

I hope so. Some of these folks take themselves and life way to seriously.

Did you read the OP's post? Your post contributes absolutely nothing to help his problem

 

[slikmrc]

Belted cases headspace off the belt on initial firing, it is not uncommon for a belted case shoulder to be .020 or more short of contacting the rifle chamber. This is heck of a lot more forming that needs to happen vs say a 6BR. And if you size belted cases by setting the die to contact the shell holder you have a good chance of seeing casehead separation at around 4 to 5 firings. Measure some of your new rounds with the .420 head space comparator vs your fired cases and sized cases to get an idea of your chamber size. One firing may not be fully sizing your brass, so don't keep sizing brass for shoulder bump. Take 4-5 cases and size till the neck is sized and will chamber in your rifle. Fire them and repeat, you will know they are sized to your chamber when you feel resistance when closing the bolt. Then you can set your die to proper shoulder bump. The case body-shoulder junction measurement you reference is not used set shoulder bump. The .420 gauge will shoulder roughly half way up the shoulder, this will measure shoulder bump.

 

[338 dude]

Does that mean threading the die deeper into the press or backing it out?

Slowly deeper until the bolt handle closes with no resistance if you have a comparator tool and can measure you would want about .002 headspace Clearance

 

[338 dude]

I bought the bullet comparator set to get CBTO length. Sounds like I can use it to get base to shoulder measurements

You can use the tool but you will need a different set of inserts to measure headspace

 

[General RE LEE]

You can use the tool but you will need a different set of inserts to measure headspaceView attachment 260673

yep I just ordered that.

 

[Tommo64]

this is Erik Cortina's video guide to setting up your FL resizing die to bump your shoulders back 2 thou or whatever bump you want.

 

[Tommo64]

These are once fire cases. If I ever get primers and actually start to reload live ammo, is a tight case fit from a once fired case going to cause pressure issues?

Insufficient head space won't cause pressure issues. It will just make it difficult, if not impossible, to close your bolt. Excessive length is a different story. If your case neck is longer than SAAMI spec, the case mouth may pinch down on the bullet, preventing proper release on firing and causing a pressure spike.

 

[Rich Coyle]

Did you read the OP's post? Your post contributes absolutely nothing to help his problem

Yes. Not only that I went back and re-read it before I posted that post.

 

[ButterBean]

Yes. Not only that I went back and re-read it before I posted that post.

Soooooo how does your post pertain to the OP's question ?