Shaving brass .

[sandrooney]

I have a Dillon 550b and sometimes when the brass goes through the sizing die it shaves brass and causes a ring at the bottom that won't even case gauge. Approx. 3 out of a hundred. It only does it on 38 SC.

Any ideas as to what is causing this.

Thanks,

SR

[superdude]

one possible cause is that the brass is excessively bulged, and sizing it is causing a ring to form near the bottom. Does it look like the brass in Figure 4 at the link below? Another possibility is that there is an alignment issue between the shell plate and the die - it's off center some how.

http://38super.net/Pages/Brass.html

[Guest]

What Superdude said!

I load .38 super on a 550 also and use a U-die which makes the "ringed" cases worse.

A couple of things - I used a .308 case, a drill, and polishing compound to put a tiny radius on the sizing die carbide insert lead in chamfer and that helped. Also find that using a little Hornady One-shot case lube (or silicone spray) helps reduce the number of "ringed" cases and makes resizing easier in general. It is caused from excessively bulged cases and I find that it happens more with nickle cases than brass. The frequency depends on my brass source. Range pickup brass - about 1-2 per 100. Mine from a practice session with my Caspian is zero. I also have a Tanfo that has a humungous chamber and will get 1-2 ringed cases per 100 from that brass. Besides the "ring" I have to watch for cases growing beyond 0.905" with really bulged cases. That will keep my guns out of battery.

With the 550 I can tell when the case is "sizing hard" and will pull it after sizing but before priming and examine it and case gauge it. If it has the ring or grew past 0.905" I toss it.

[HI5-O]

I've run into that issue recently, don't know why b/c in the past, there were no issues. I bought a CasePro and it's reduced the occurrence rate but some still get shaved. Used the undersize die and with the CasePro'd brass I just use the Dillon die (38SC).

[sandrooney]

I took out the primer punch and man was the die dirty. I am hoping that is it. I will keep you posted.

Thanks to all,

SR

[sandrooney]

superdude,

It looks exactly like the bad one in figure 4.

Thanks SR

[Guest]

Just as a reference - I loaded up about 1k and here is a photo of my "hard ring" rejects from that batch. All of these were caught at station one after sizing but before priming.

[sandrooney]

That's what mine look like only not as bad.

Thanks,

SR

[Steve RA]

Oversized chamber, excessive pressure or both cause that.