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Discussion Starter #1
When a bullet travels through the transonic range the frictional pull trying to
slow it down is from four to five times greater than the pull that exists at
subsonic velocity. Simply put, this differential pull causes instability. A
stable, round-nosed, flat-based bullet (like the .22 LR) will he less accurate
in the transonic range. Inherently unstable, hollow-point, boat-tailed bullets
(with the preponderance of mass to the rear) will lose all stability in the
transonic range, tumbling end-over-end and losing any semblance of accuracy at
that speed.

Thirty years ago, those who drove Chrysler vehicles on slippery roads in the
northern states found that, in a situation where control was lost, the vehicle
would spin and settle into a rear end-first attitude, because the rear end was
heavier than the front end. Those who drove Ford products (which typically had
less rear-wheel traction on ice) soon learned that the heavier front end caused
the vehicle to be more stable in a spin. Its natural movement in a minimal
traction situation was front-end first. Sharply pointed bullets have the
heaviest end at the rear, and they take a much greater spin rate to keep them
pointed in the right direction. Bullets with blunt points and hollow bases (Like
hollow-based wadcutters) are inherently stable in flight. They fly straight,
even without spin.

In terms of effectiveness on live targets, it is very hard to beat a blunt-nosed
or flat-tipped bullet. Put another way, a subsonic bullet that is a true
cylinder will deliver more shock, hemorrhage and trauma than any other shape.
Sharply pointed and round-nosed projectiles will slip right through, while
causing minimal damage. It has been said that some .30 caliber projectiles are
designed to expand at 300 m/s or 1,000 fps, but this remains to be proven to my
satisfaction.
(not neccesarilly my opinion...just something I found from Finland where they do a lot of work with sub-sonic and suppressed loads)

Sharply pointed bullets will penetrate deeply at subsonic velocities - pushing
nerve tissue and blood vessels aside, rather than cutting them. Unless the
bullet hits the base of the brain or a major nerve center, the animal will run
away, usually to die a slow and agonizing death. Most pointed and round-nosed
.30 caliber rifle bullets are totally lacking in knockdown power at subsonic
velocities. We hear the same stories of subsonic .30 caliber bullet inadequacies
over and over again, and are frankly quite tired of them. Subsonic .30 caliber
bullets will not expand in large animals. The only effective .30 caliber
subsonic bullet will have a totally flat front end.

...another little excerpt, very interesting...the birth of the Whisper?

The next step up the ladder of higher subsonic energy is the move to a .30
caliber weapon. The .308 is a logical place to start, and (with a light charge
of fast powder) it can he effective in a weapon that is designed to he both
subsonic and supersonic. A 254 mm or 1 in 10 inch twist will stabilize up to a
200 grain, round-nosed, flat-based bullet. However, the extra room in the .308
case provides a substantial cushion, which can cause problems with efficiency
and consistency. The most ideal situation results when a cartridge case is just
big enough to hold its charge of powder and a bullet, with no room to spare. In
the 1960's a fellow named Joe Apache necked a .223 case up to .30 caliber. The
result was an interesting cartridge called the .30 Apache, which sat ignored for
quite a number of years.
 

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Hollowpoints at Mach III

If this is true, why is my most accurate load in .223 a 50 gr. Speer TNT at 3000 fps ? And why are match bullets hollowpoints? I am not disputing the posting.......well, maybe I am.
 

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Discussion Starter #3
This article was about transonic and subsonic loads...

...it isnt relating to super sonic loads. Subsonic is less than the speed of sound, transsonic is 'at or about' the speed of sound. I dont doubt the accuracy of those bullets in your 223 or any other caliber for long range shooting. I dont have anyhing to back up this data, it is just an article that I read and I thought the rest of us might find it interesting. It also states that a man named Joe Apache apparently was one of the pioneers necking a .223 to .308 on the 1960's, and that it all but dissappeared until Grendal Arms (now Kel-Tec) picked it up in a similar case for a suppressed load in the m-16, which eventually evolved into what is now called the 300 Whisper. Nowhere is the name J.D. Jones, or SSK Industries ever mentioned. I have E-mailed Kel-tec to try and get some history on this or to confirm these facts...possibly J.D. or his associates were working with Grendal arms back then.
 

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Here's an interesting read for Whisper re-l

Robert You found a very good article and refrence point. I have played with this for a few years as have some of my freinds. I do like subsonic loads very much becuase you do not get the destablization. Another that I have played with latly is a load that will stay above sonic speeds to a specific range ie 200m for IHMSA. When shooting a cast of jacketed bullet you still have to take pressures and such to achive this. I am lucky or some would say unlucky of owning a barrel that loves 200gr + bullets. Now as we have discused in the past Jacketed bullets in a 200gr or larger are long. Where as the cast projectile can be made shorter while retaining the same bearing surface or acctually gaining surface. Bearing surface not wieght is what adds in accuracy with fast twist barrels. If you look at the formula that Donna of the swaged bullet forum Ishould say make your own condom forum :p has on her web site and that I have on mine. you will see a great deal of diferrence on comparing bullets of the same wight but diferrent bearing surface.
Now lets look at cartridge capacity with defferent bullets take a 200gr Sierra match king in .308 and one of my 200gr bullets.We will use my 30br as a referance. In this case the 200gr Sierra extends in to the body of the case allmost .25 inch where as my cast bullet is flush with the bottom of the neck. Now if I load the jacketed bullet to maintain speed above transonic. I have to use a powder in the AA 2015-2230 burning range and it will be verry stout. It will actually produce a lot of muzzler flash and jump. Allot of this muzzle jump(recoil) is due to the fact of the hard drawn jacket raising pressure. I have load from a disk and ran the numbers it is high. Now I can take a cast bullet drop the charge some but not much. we stillhave recoil and flash but not as much. Now these past few weeks I have been working with AA 8700 a very slow burning powder. We statrted with a 3/4 full case by volume (Load data was developed by useing one grain powder to one grain of water volume.) This load did suprise us in that accuracy was inhanced and recoil was reduced to allmost nothing I could acctualy spot for my self at the range.Even if velocity is down 10-20% it is not bad as long as I stay at 1050fps or higher at 200m heck I could live with transxonic disturbance at 195m for rams. But would rather have it happen at 225m. Half size target accuracy is then achived.
As for the whisper cartridge you will find that alot of people have take credit for some thing they have only a small amount of input . Take JD using a 225 Case others have done it with a 221fire ball. Now I am slighly complaning but not much as Barnes did it first. Once when Belm and I were talking I brought up a cartidge based on the 30br( did not know some one was allready chambering it ina TC) Well Belm said send me X amount and I will make one . I did not have the money so it did not hapen. Now he is marketing a 30 1.6 Belm well aint that a 30br or even a 30Herret? What I am saying is that none of us are doing any thing really new. **** the 32/20 was the first whisper in my book.
 

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Subsonic

I use a 32 H+R mag. 10" Contender pistol for IHMSA field pistol. I shoot a cast bullet, Lyman #311316 (113Gr.), subsonic. To keep to bullet sonic at 100 yds. the higher powder charge would increase the recoil. I use a rifle scope so recoil is a consideration. Starting the bullet sonic and having it drop to subsonic before reaching the 100 yd. target, buffets the bullet, and harms the accuracy. My subsonic load will shoot .75" at 100 yds.. I think if I used a scope with more powder it would group even better, I only have a 9 power scope on this barrel. I have developed subsonic loads for a few rifles with blunt bullets, with amazing accuracy. 8)
 
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