Lyman Expansion die bending case rim in

[mpmo]

Any ideas why my new Lyman expansion die is bending in the rim in?  This happens about every 10 rounds.  This is on a Mark 7 EVO.  

 

 

[AHI]

Case is wobbling around . Die center is hitting on rim. Slow down index.

[mpmo]

I have the shell plate retaining spring (the one that holds the rounds to the plate decently loose as demonstrated on the .223 tune video they published.  Should I tighten it down a bit?

 

[AHI]

I would tighten it up and observe how smooth or ruff the press indexes . With this and your powder measure issue. Going to say it's fairly ruff.

[Tom Freeman]

Consider grinding a bit more taper to the bottom of the plug to allow it to center itself a little easier.

 

And slow down the index speed and/or bump up the pause at the top of the stroke to allow the case to stop moving around.

[Farmer]

I know it’s a pain but along with everyone else’s suggestions,  it doesn’t hurt to chamfer the insides of the case mouths too. It’s sometimes hard to see but there can be a pretty good ridge on some. 

[SSGJohnV]

Loosen your shell plate retainer spring more than you think you need to. 223 likes to "cam" inward towards the ram. Nature of the beast with a 22 caliber case mouth and a tall, spindly case. 

 

Running manually, let there be a brief pause before you bring the tool head down again. In automated, a dwell of 2 is recommended. 

[erwos]

Make sure you check the M-die itself as well. I've had them unthread the expanders on me.

[Farmer]

12 hours ago, erwos said:

Make sure you check the M-die itself as well. I've had them unthread the expanders on me.

X2 I lock-tight all of mine before I even use them.