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6/17/2007 6:26:15 AM EDT
I would like everyone to post "SUB SONIC" loads for the .300 Fireball/Whisper

Lets see what ya got

I think we are on to something here...what about barrel lengths?
6/17/2007 6:28:24 AM EDT
[#1]
I use 9 grns of H110 under Sierra 240 grn MatchKings.
6/17/2007 8:27:00 AM EDT
[#2]
I have posted all of my load data (both subsonic and super sonic) for the 300 Whisper(r) a.k.a 300-221 fireball here:

http://reloadersnest.com/frontpage.asp?CaliberID=135

All but three of the loads listed under "Not yet verified user loads" are mine. So as you can see I have had some experience with this round. Additional reloading data can be found here as well:

http://www.accuratereloading.com/300whisper.html

You can also find a great source of subsonic data here:

http://www.accuratepowder.com/data/PerCaliber2Guide/Handgun/Standarddata/30Cal(7.62mm)/300%20Whisper%20page%2076.pdf

The Sierra reloading manual 5th edition and the the most recent Hornaday reloading handbook also has reload data for the 300 Whisper(r) data.  In the Sierra manual the starting loads for bullets 200 g and above are subsonic.  

My favorite powder/load is 7.5 to 8.5 g of AA#9 (the actual weight depends on the ambient temp.) with bullet weights of 165 and 180.  Be careful using powders with a burn speed of H110 or slower in cold weather.  The subsonic data listed in the two reloading manuals are probably safe at colder temps.

Shooting subsonic can be a bit tricky (kinda like Goldie Locks) because the speed of sound and the buring rates of the powders change with temp. So one day your loads will be just right other days they can be too hot/fast (crack) and on other days they can be too cold/slow (whoommff). On really cold days you can get bullets stuck in the bore.  Check this web site out (I am glad to say this was not my barrel):

http://feistyrooster.com/300x221/300x221barrelsplit.html

320pf
6/18/2007 7:25:39 AM EDT
[#3]


9.2 gr of H110 w/ 220 gr Sierra HPBT
CCI small brench rest primers
using new Winchester 223 cases cut and formed to 300/221 on redding dies

9" barrel
6/18/2007 7:35:18 AM EDT
[#4]
You might also take a look here:

www.quarterbore.net/forums/forumdisplay.php?f=38

and

www.300whisper.com/subsonic.html

and

www.300whisper.com/supersonic.html
6/23/2007 6:59:34 AM EDT
[#5]
how many have AR's in .300?
6/26/2007 1:24:18 PM EDT
[#6]

Quoted:
I use 9 grns of H110 under Sierra 240 grn MatchKings.


I use 9gr of H110 under 250gr MatchKings.
They discontinued that bullet, but I still have a big box of them.
6/27/2007 5:56:53 PM EDT
[#7]
762-4-U,

I have a 16 inch Olympic Arms barrel from Del-Ton.  The gas port is about 1/2 inch closer to the chamber than the standard pistol length gas port.

I have another 16 inch Olympic Arms barrel in which I have moved the gas port to the standard carbine position.  I have not had a chance to shoot this barrel very much yet.  

I find that I am shooting the 300-fireball more than I shoot  my regular 223 AR15.  It is just a lot more interesting to shoot that a regular AR.  In fact, I am thinking about getting a third one with a 20 inch barrel and the gas port in the carbine position.  

320pf
6/27/2007 8:02:00 PM EDT
[#8]

Quoted:
I am thinking about getting a third one with a 20 inch barrel and the gas port in the carbine position.


Have you tried that one I sent you yet?
6/28/2007 3:17:01 AM EDT
[#9]
Randall,

I hope to have all the bits that I need by this week end. I ran into two issues... both pretty easy to fix. The first one was with my barrel wrench, it would not fit around the barrel contour up by the chamber, so I had to remove a few thousandths from the wrench... so now the wrench fits around the barrel. Problem one solved.  

The second problem was, I had to order another gas block because the one that I had planned on using was originally on the pistol length Oly barrel and I could not separate the gas tube from the JP gas block.  I think that some of the lock-tite that I put on the adjustment screw may have got into the tube assembly.  I did not want to risk breaking the tube and have some of the tube stuck in the JP gas block. To make a long story short, the new gas block should be here by Friday.  

So the plan is to take it to the range this weekend and see what an additional four inches of barrel gives me.

320pf
7/6/2007 4:54:04 PM EDT
[#10]
still looking for more load data.
7/22/2007 6:44:40 AM EDT
[#11]
Still looking for more info
7/22/2007 7:07:36 AM EDT
[#12]



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