300 Whisper/Fireball

[dlt223]

Hello All,

The chamber on my ".300 Fireball" was cut with a reamer that was marked .300 Whisper.
J.D.Jones only sells Rifles or Uppers and they are not what I would call reasonably priced.
Jones claims that Redding .300 Fireball dies do not produce brass that correctly fits a Whisper chamber.

I form brass from new Winchester .223 using Redding dies and have not had a problem with either chambering or firing.
I would recommend against anyone forming brass from Military.
First You may end up with the Hazardous thick neck condition and secondly Military brass is not of uniform quality.

.221 Fireball cases are about .22 each .223 cases are about .135 each.
Yes it is a little more work But I prefer using the neck down method.
My neck walls measure about .011" and I know they have not been overstretched.
I trim to 1.400" and after firing the first time they are only a few thousandths shorter.

This is a length that works in My chamber, It may be Hazardous in yours!
Before deciding on a trim length you should KNOW what your chamber dimensions are.

Corbon produces their brass from Military and I have found that the neck walls are not of a uniform thickness.
Corbon brass length varies from about 1.333" to over 1.362". Whisper spec is 1.350"
Heres hoping that Starline will soon produce brass for us Whisper shooters.

Talk to Y'all Later, Dave