Sticking expander/decap assembly

[JBS]

When I get an expander ball that acts this way I will remove the rod and ball and put it in the lathe, substitute hand drill or drill press and polish the ball with 800 to 1000 grit paper. As soon as it is polished to a mirror stop. You do not want it undersized just polished. This normally fixes the problem. Also note that as the case is used the neck will become work hardened. Some cases do this faster than others, 5.56 / .223 are the worst. If the ball is very hard to pull back through it is probably time to anneal the case necks. I do them in lots, every 4th to 5th loading for 06 class cases, every 3rd for 5.56 class cases.

[Mudcat]

If you aint got messed up case mouths, dont use an expander!! All of my dies I use on my bolt guns have had the decap rod/expander ball removed. Just one more thing to mess up my brass!

Neck tension comes from the sizing die NOT from the expander ball. How else do you think we could fire all these rounds without using one! :-)

John

[jmoore]

The problem is that the die manufacturers don't know how thick the case necks will be (up to a point) , so they made the sizing die suitable for sizing the THINNEST possible neck thickess down to a size that will adequately hold the projectile. The expander ball's function is to size up the thicker case neck ID's to a point where the bullet won't be distorted upon seating.

If you want to minimize cold work on your cases get the Redding type "S" dies that have changable case neck sizing inserts. I still run a ball in conjuction w/ these just to round things up in case of dents and such, but the cases are worked less, stretch less, last longer, and produce most excellent accuracy (in those rifles that will achieve sub 2/3 MOA or so the difference is particularly noticable).

It just depends on what you're trying to achieve whether its worth the small expense and extra effort involved.

[USSR]

If you want to minimize cold work on your cases get the Redding type "S" dies that have changable case neck sizing inserts. I still run a ball in conjuction w/ these just to round things up in case of dents and such, but the cases are worked less, stretch less, last longer, and produce most excellent accuracy (in those rifles that will achieve sub 2/3 MOA or so the difference is particularly noticable).

I've got the Redding Competition Die Set which uses the bushings. Best thing since sliced bread. With various size bushings, I am able to vary the amount of neck tension desired with different makes of brass. I handle the "roundness of neck" thing by inserting a knife sharpener (long cylindrical tapered rod) and giving it a tap to remove any dents in the case neck. Decapping is handled by a Lyman Universal Decapping Die.

Don