Question about roll sizing

[Antoine]

Hi guys,

When you roll size, do you still need to full size? I have zero experience with this method and I asked someone to roll size some 9mm brass for me. At my surprise, most of them had an oversize neck so the bullet would drop free. I thought that a roll sizer was a 1 step process.

I reprocess all my brass on my XL650 and noticed that I still have that ugly coke bottle profile. Why does a commercial reloader can produce some nice reload that looks like factory ammo and my reloads looks terrible?

Any imput will be appreciated.

[jmorris]

Roll sizing only does the lower part of the case. You have to size and deprime as normal.

You don't have to have the coke bottle, back your size die out and slowly bring it down so a sized case will pass a case gage and stop there.

Many die instructions over size the case (aka hit the shell plate with the die). If you are using a "U" die you are obviously going to have the coke bottle effect.

[Antoine]

Yeah I thought about that, thanks for your imput jmorris.

[euxx]

Is there anything bad about "coke bottle" thing?

[fltbed]

Is there anything bad about "coke bottle" thing?

No.

In fact, the little shoulder formed below the bullet base helps prevent bullet set back from the chambering forces.

Jeff

[Pat Miles]

Roll sizing only does the lower part of the case. You have to size and deprime as normal.

You don't have to have the coke bottle, back your size die out and slowly bring it down so a sized case will pass a case gage and stop there.

Many die instructions over size the case (aka hit the shell plate with the die). If you are using a "U" die you are obviously going to have the coke bottle effect.

My CasePro resizes my brass, 38 SuperComp and 40, from the top of the extractor groove to the top of the cartridge. My 38 SC 650 is setup with a Dillon resizer/decapper in the first station and a U-Die (less decapping pin obviously) in the second station. This was my setup before I bought the CasePro and I left it as such. Some day I'll do some measurements on cases and see if I can do away with one of the resizing dies.

Pat

[usmc1974]

I just run any and all cases though my SDB. Never had any troulbe before. I too don't know a thing about roll sizing.

[jmorris]

In fact, the little shoulder formed below the bullet base helps prevent bullet set back from the chambering forces.

Must be why factory ammo is like this....hmm.

My CasePro resizes my brass, 38 SuperComp and 40, from the top of the extractor groove to the top of the cartridge.

I have two in four calibers they do the same thing as your machine does.

The thin case mouth distorts instead of resizing as it is only in contact with the surface in two places 180 degrees apart. Unlike a die with 360 degree contact.

In fact if you check cases before the casepro some will drop in a case gauge (before FL sizing) and after the casepro (again before FL sizing) they won't. I've done it.

[Emerson]

Definitely still have to full length size after roll sizing.

[G-ManBart]

Is there anything bad about "coke bottle" thing?

No.

In fact, the little shoulder formed below the bullet base helps prevent bullet set back from the chambering forces.

Jeff

+1

It looks weird, but is actually a good thing. R,