Thread: 300/221(300 Whisper)

Anybody reload for this cartridge? I think I'm going to build an AR15 upper for this caliber and was wondering what all I need.

Last time I checked this was still a wildcat cartridge. I picked up "one" piece of brass from the range that I could not figure out what it was until I researched its dimensions which turned out to be a whisper. This was a 223 LC brass cut down and re-formed to the 300 whisper. The case is very small compared to the projectile you will be shooting. What do the ballistics look like? I would look also at the 7.62x39 uppers if you want a 30 caliber Ar-15. Brass, Dies, and Commercial ammo is more readily available for the 7.62x39. I also like the 458 SOCOM.

Of course I want a 308 so if I go the AR route I will have to build off the AR-10 design.


I think its a neet cartridge but would be reluctant to build a wildcat.

If you ahve not read here is a good read.

Handloading, Bench Testing & History Of J.D. Jones incredible 300 Whisper