Can I use smaller expander button, such as .223 expander for .243?

[jsu]

Hi,

I use .243 RCBS full length sizing die to just size the neck and found the expander button makes the sizing a tough job. So I tried .223 expander and found it's a lot easier to size now. Bullet seating is just like normal.

May I ask if there is any risk if I continue to do that.

Thanks

 

[farmmer dan]

Too me that does not sound like a great idea. I am not sure but the brass may be to tight around the bullet causing possible higher pressure than normal. generally, before seating, I thick the brass should be .002 smaller than the bullet.use the .223 ball and lube each case with ether a brush or a Q tip on the inside. You don't have to use much lube. In fact, I find just cleaning the inside with one stroke of a lightly lubed brush helps a lot.

by the way welcome to THR.

 

[rcmodel]

+1
Lube the case necks and whatever the problem is will go away.

It's possible to deform the bullets by forcing them into sized cases that haven't been expanded to the proper size to fit.

It may work the first time or two with new brass, but after the necks work-harden it probably won't.

rcmodel

 

[Steve C]

You are probably not doing any neck expansion at all with a .223 expander in a .243 die and case. While you may find the bullets seating fine in the particular brass you have been loading you can run into problems with different brands that may have a thicker construction. You may also be reducing the bullet diameter enough to affect accuracy when you force it into the narrowed cartridge neck. As to if it's OK, try some of the ammo you loaded using the sub caliber expander and see if it shoots as well as the stuff you previously loaded using the proper expander.

Let us know the results as "inquiring minds want to know."

 

[Otto]

You can buy a carbide expander made to fit your RCBS die.
http://www.midsouthshooterssupply.com/item.asp?sku=00005044692
Also, Imperial sizing wax is the lube of choice...






Welcome to the forum.

 

[IndianaBoy]

Just get a neck sizing die.

 

[mkl]

I beleive the purpose of the expander button is to get the _inside_ of the neck to the correct dimension. Brass thickness varies, so first the die sizes the neck "too small" and then the expander button opens it up to the correct interior dimension.

As was said, don't think a .223 expander button is opening up the neck at all. Lube the inside of the case mouth, use the .243 button, and most of your problems should go away. A neck sizing die is an option, but just backing off the regaular die (like I assume you are doing) should work okay.

 

[jsu]

Thanks so much for your useful tips. I will switch back to .243 expander and use lube now.

 

[Matt-man]

I beleive the purpose of the expander button is to get the _inside_ of the neck to the correct dimension. Brass thickness varies, so first the die sizes the neck "too small" and then the expander button opens it up to the correct interior dimension.

You are correct, sir.

Another option is to use dies with neck bushings. You choose the appropriate bushing that sizes the neck to the correct size for your particular bullet and brass combination, so you don't need an expander button. Course, these are fairly expensive.