I have been looking all over the internet trying to find the answer for making and then loading a 300 Whisper rounds using the .223 Rem as a parent case. There is conflicting information all over the web about whether this is SAFE or not. Most of the concerns, it appears, is that the case's neck contains too thick of brass and may not allow it to properly expand in the chamber and release the bullet. JD Jones from SSK, the creator of the round, appears to advocate the use of expanding the .221 Fireball case to make 300 Whisper. But he also goes onto say it can be done from the .223Rem. On top of that, there is not a lot of info out there about the case and what the measurements SHOULD be. I have ordered a set of 300 Whisper factroy loads from Corbon, but they are backorder so I have no reference. On top of that, I have a ton .223REM laying around and all the RCBS dies needed to make them into 300 Whisper.

If you all could provide the following info and other info you find important, it would be great.

300 Whisper

neck wall thickness using .221Fireball
neck wall thickness using .223Rem
case overall length
loaded round(Case+seated bullet) lenght

Also, if anyone knows a good load to make a 168gr bullet supersonic(For deer) and subsonic I would apperciate that. Ideally, using the same powered but that produces goo groups at 150yds

You have to trim down the 223Rem brass so much it's not worth the trouble. Just buy 221Rem brass and resize it. You will need to to it in steps, first to 26 cal then to 30 cal with a fire forming.

I still have some old reloaded ammo here I would sell you. Most guys would pull the bullets and reload them themselves just to be safe. Pm me if you want to buy the ammo cheap.

If he doesn't want it Dave, I'll take it all.

Thanks,
lawndart

PS I second the advice above. 221 brass is cheap, and easily obtained.

Can you answer my question? Im looking for measurements.

Thanks

Anyone, Anyone.... All it takes is a factory round and a micrometer.

I do have a pile of 223 cases a buddy ran through his 300W sizing die, but don't have the brass or a mike handy to check case thickness.

I know my buddy said they worked fine through his 300 W, which was a Contender barrel from SSK. As far as whether you'll have problems with 223 brass vs 221, I'd say that would depend on how tight your chamber is. Unforunately JD Jones is partial to keeping his rounds proprietary and is prone to suing folks, so you won't find alot of info out there. Also with wildcats, dimensions vary, so you need to see what will work in your gun.

There are a few websites that have 300W data on them.

To be safe I'd make your brass from 221 cases, and measure fired cases to see how much the necks grow on firing. Then you can see if 223 brass will be safe in your gun.

It's just way too uncertain to use others dimensions on wildcats, you need to know what your gun measures to be safe.

Send an e-mail to Pacific Tool and Guage. They have drawings for the 300/221 reamer.

I'll measure a loaded factory round tonight as well.

LD

PS Thanks for not taking f224 up on his very kind offer.

Bump.

I no longer need the case thickness and what not. I did a few .221 fireballs as well as .223 rem tonight and every thing appears to be that same once you get them to a 300/221

All I need is OAL.... I desperatly need over all lenght.

Depending on who cut your chamber, the OAL will vary between 2.10" to 2.26".

2.26" is max for decent feeding out of most AR magazines.

If you aren't shipping out to war with a spec ops group in the next week you may have time to do the following:

Load some to 2.16", and shoot a dozen or so.
Send three empty cases to Stoney Point. They will modify those to work with their OAL/distance to land engagement tool.
Test your projectile of choice in your rifle, as directed.
Set your OAL with that given projectile at .010" short of land contact, or no longer than allows reliable feeding out of your magazine(s), whichever is shorter.

It all comes down to how your chamber was cut, by whom and what reamer was used.

LD

It's a complete upper from Olympic Arms if that helps.