7mm mag case sizing

[BW64]

I think I got it. Used new brass but.......why does the fired & sized brass feel tighter than the new??

BW

 

[Bart B.]

.....why does the fired & sized brass feel tighter than the new??

Those cases are a bit larger than new ones. Resizing dies typically don't return fired cases to their original dimensions as new, unfired fired ones.

 

[BW64]

So should I set the HS with fired & sized brass?? Dam I feel like a rookie & I've been doing this for years!! Dam belted cases!

BW

 

[Bart B.]

Set the sizing die in the press to push the fired case shoulder back .002 inch.

It doesn't matter where on the case shoulder the gauge bushing contacts the case shoulder.

Do this by measuring the fired cases with the Hornady gauge. If it measures 2.046", then the full length sized cases should measure 2.044". A couple thousandths spread is OK. Twisting the die in the press 1/10th inch about its circumference moved it about .002" up or down.

Very good accuracy and long case life happens this way.

 

[BW64]

Set the sizing die in the press to push the fired case shoulder back .002 inch.

It doesn't matter where on the case shoulder the gauge bushing contacts the case shoulder.

Do this by measuring the fired cases with the Hornady gauge. If it measures 2.046", then the full length sized cases should measure 2.044". A couple thousandths spread is OK. Twisting the die in the press 1/10th inch about its circumference moved it about .002" up or down.

Very good accuracy and long case life happens this way.[/QUOTE

Yep. That's the easy part. Do that on my .308 & 6.5cm.


BW

 

[fguffey]

Those cases are a bit larger than new ones. Resizing dies typically don't return fired cases to their original dimensions as new, unfired fired ones.

Who measures? I suggest the reloader measure before firing and again after firing. I also suggest the reloader save a few unfired, new over the counter cases; nothing like having something to compare when comparing.

F. Guffey

 

[CoyoteTan]

Set the sizing die in the press to push the fired case shoulder back .002 inch.

I think you meant 0.002"

 

[Bart B.]

I think you meant 0.002"

What's the difference in length?

 

[Bart B.]

Coyote Tan,

Comparing .002 inch to 0.002" , I see one of them taking up about 32% more horizontal space in a line of typed text for the font style and point size used. Compare the underscore lines' length below each and you should be able to tell which one is biggest in length.

 

[243winxb]

Old thread warning.

why does the fired & sized brass feel tighter than the new??

When full length sizing, headspacing (head clearance) a belted magnum off the shoulder, the area in front of the belt may become unsupported in the chamber on firing. Brass will bulge.