Bullets shrink

Do cast bullets shrink after they have been pulled?
Click to expand...
No, but in the instance of having used a Lee Factory Crimp Die (the kind with a carbide sizing ring at the mouth of the die), on pistol cartridges one may find the bullets to be undersized due to being squeezed down by said carbide ring. Some users report that their Lee Factory Crimp dies do not do that, but on mine I found that they did, so I removed the rings and only used such dies for their crimping feature.
 
No, if they are "swaged" down while being inserted into or after that are in the case to a smaller OD, they won't "spring back" to where they were before.

They don't "shrink" after, rather already "squished" before removal.
 
I am using a Dillon die set and before crimping a seated bullet does not shrink, only does it after crimping and then pulling
 
Back the die out and lower it just a fraction of a turn at a time until the bell is removed enough so it drops into and out of a casegauge or your barrel and you should be good to go.
 
Lead is a soft metal easily distorted, but pretty stable by itself. A tight case can swage (squeeze) a bullet down as it's inserted. A roll crimp can swage/scrape a bullet as it's being pulled out of the case. A taper crimp die can swage the bullet if too much crimp is installed. And the worse offender is a Lee FCD for pistols. The FCD is a "post crimping sizing die" that can, and often does, swage cast bullets down before/after crimping by the carbide ring at the die mouth...
 
The Dillon die applies a taper crimp. If applied too firmly, it could shave a little lead. But if you find lead missing, I think it is more likely the case was inadequately flared and shaved it off as the bullet was seated. Examine your seating die for a build-up of lead leftovers.
 
Molten lead (like everything else) shrinks as it cools. Once it is solid, it is stable.

Bullets don't shrink.

They are ALL squeezed into the case. The same amount of squeeze distorts lead more than copper. That's why pulled bullets can come out with smaller measurements. They have been squeezed down by being loaded in the case.

Not shrink.

Crimp will squeeze them too, but in one spot, not the entire seated length of the bullet like the case neck does.
 
When you cast your own bullets, the bullets will shrink, or expand, or neither, as the molten alloy solidifies, depending upon the constituent metals in the alloy. When water freezes, it expands. Some metallic elements do likewise. The as-cast diameter of your bullets will vary if your alloy ratios vary.
 
Last edited:
You must log in or register to reply here.
Back
Top