I am considering a 300 Whisper upper.  I read many good things about the caliber, but few of the comments I read are specific to the AR.  I've heard that there are sometimes problems getting the .300 Whisper to feed well in AR mags.  Anyone care to comment on this issue?

Other remarks about the .300 Whisper, pro or com, would be appreciated.

I've got two ARs in 300 "whisper" (or 221/300 fireball..whatever you want to call it so as not to piss off JD Jones)...both 1:8 16" A4s, one pre, one post.  Both shoot well with Corbon factory loads, and with the reloads I've tried.  No problems feeding from regular mags, although trying to get full capacity is almost impossible.
Sluggo

I like mine but its not a whisper, its a 300-221.  I haven't had any problems feeding at all.  I have shot everthing from 110fmj carbine bullets to 240gr sierra's, both sonic and subsonic.  What is cool are tracers that are subsonic.  They leave a huge smoke trail and seem to take forever to go 300-400yds.

I shot some M2 AP loads and they still did a number on trees even though the velocity was lower.  

I picked up some blue tips at knob creek and they are impressive too.  I was afraid the whisper wouldn't have the velocity needed for the blue tips but they worked fine.  Expensive as crap though.

All in all its a fun toy that could be used for hunting if need be.  Mine is plenty accurate too.

Hey, guys--

Does the .221 Fireball have more case capacity than the .223 Rem/5.56?

If not, why not just use a .223 brass necked-up to .308"? That would likely give the standard everything, right?

Or is it that the neck/shoulder on the .223 configuration wouldn't allow for consistent headspacing?

Inquiring minds want to know...especially since a cheapo upper with a custom barrel in it would be neat, with no change of lower parts or mags being involved.

And in a new, semi-wildcat caliber?!? Just icing on the cake, ba-by!

Please respond! I can't wait to call RCBS for the dies!!

Regards,

Impatient FastVFR800

I just built a 300/221 AR and am in the process of working up some supersonic loads. You just can't neck up the 223 to 308, in order to get it to fit in the case you'd have to seat it in so deep that the case mouth would fold over to bullet ogive. Thats why you have to cut the cases down and even that presents some problems due to varying case thickness. You could end up having to turn the outside of the case necks and that will really slow down your reloading speed.

Oh, of course it would.

I was thinking that, like making .44 Auto Mag brass from .308, I could inside-ream the new neck after trimming to length a .223 and then running the brass thru a .300 W forming die.

Is there any advantage to using the more expensive
.221 brass?

Since the forming/inside reaming needs done only once, I was thinking the .223 cut-down would be more viable, if more labor intensive.

Regards,

FastVFR800

I assume you all have seen my 300 Whisper page but if not...

[url]www.quarterbore.com/300whisper[/url]

If you would like to share pics or a story about your 300 Whisper or 300/221 Fireball I would love to host a page for you!

As for the 221 case, it is much shorter and has a smaller charge capacity.  When the huge 220-250 gr bullets are shoved in the case it leaves fairly little extra case empty even with very small charges.  This is the real secret to the 300 Whisper!

I had a 300/221 by Olympic Arms and I never got very far as I had some technical problems and Olympic lost my business for life!  I want to get my 300 Whisper Upper project moving but I always seem to find something else to spend my money on...  My upper will be an SSK Upper as described on the webpage....

It's a great cartridge and I have heard from many people that have had great luck with the SSK uppers as well as those by the Pirates as JD refers to everybody else's product!

[b]fastvfr800[/b]: You may have already gotten an answer, but if you haven’t [b]Randall_Rausch[/b] of [url=http://www.ar15barrels.com]AR15barrels.com[/url] has a [url=http://www.ar15barrels.com/prod/300-221.shtml]page devoted to the .300-221[/url] (aka .300 Whisper). On it, he states that:Hope that helps.