Home Forums Reloading Big Game Rifles Ttsx expansion penetration testing

http://www.shootingillustrated.com/mobile/article.php?id=463

Based on the Info below... Same bullet with different impact speed changes size of wound channel and penetration.


"The most important bullet characteristics with regard to terminal performance are expansion, weight retention, penetration and wounding qualities. Without knowing these, you are pretty much shooting in the dark as to bullet suitability for a particular game species and downrange performance. To test these traits across a spectrum of muzzle and impact velocities, I shot sample 130-grain TTSX bullets through a .300 Whisper, a .308 Winchester and a .300 Weatherby Magnum into Bullet Test Tubes with Extenders at 25 yards.

With a muzzle velocity of 2,013 fps, through the .300 Whisper the TTSX expanded to .541 inch, retained 129.2 grains of its weight, penetrated 14 3/4 inches and produced a .667-inch-wide wound channel. At a similar velocity, the TSX expanded to .439 inch, weighed 130 grains, penetrated 13 1/2 inches but veered severely off course at the 6-inch mark while creating a .638-inch-wide wound channel.

Propelled through the .308 Winchester at 2,878 fps, the new bullet enlarged to .614 inch, kept 129.3 grains of its weight, pierced 15 inches into the media and formed a 2-inch-wide wound channel. The most punishing evaluation came when I launched the TTSX from the .300 Weatherby Magnum at 3,562 fps. It penetrated all 20 inches of Test Tube and Extender and exited, but not before leaving a 2.371-inch-wide wound channel and shedding a single, 11.8-grain petal at the 11 1/2-inch mark. It�s possible to argue the recovered bullet weight would be between 117.3 and 117.6 grains. "


so here is the results
130 TTSX
speed---- expansion --- penetration-- would channel
2013 --- .541" --- 14.75" -- .667"
2878 --- .614" --- 15" -- 2.00"
3562 --- n/a --- 20"+ -- 2.371"

The highest velocity had the deepest penetration....interesting.

But the different in wound channel between 300 whisper and 308 was 3x the size!!!

velocity....

Who says "it doesn't matter"?....of course it does.

Yup. Pretty typical of mono bullets. The faster they hit, the harder and deeper they smack.

Jordan the faster you drive some bullets,the expanded petals fold back flatter against the shank,creating a somewhat smaller frontal area....this allows a bit more penetration I think.

Yes Bob, even with the TSX/TTSX's, I've driven them so fast into test media when they are retrieved they look like a 'brad' or "bradded rivet", petals completely gone with a bit of nose slump left.

Gunner

Bob, you're absolutely right. Although, even the bullets that impact at high velocity and expand to a fairly wide diameter tend to penetrate better than those that impact at a slower speed. I believe to some degree it's because higher impact velocities don't cause partial disintegration, as with many lead-cored bullets, so the increase in momentum due to the increased impact velocity is not offset by a loss in bullet mass. Essentially, because monos retain their weight so well, added velocity aids the bullet in penetrating deeper, which is the opposite of what we are used to with traditional bullet designs.

I believe this thread is touching on the "knock" of the TTSX/TSX bullet. I'm a firm believer they need to be driven fast to reach maximum potential.

I feel as though some of the failures -- for lack of a better term -- are from guys trying run traditional weight bullets instead of stepping down (180 in 30-06, 130 in 270, 140 in 7mm etc.).

Drop a few grains from your traditional bullet weight, push the lighter bullets hard and watch the results.

bingo!!!

I wouldn't dare hunt deer with a 168ttsx out of my 308 ..... Would it work? Probably but it wouldn't expand as fast as my 130's launched at 3050....

I swear I'm toying with the idea of ordering the 110ttsx in 30 cal and seeing if I can get 3300-3400 out of them. Think that would penetrate?

Yep -- especially on deer size game. It doesn't take a 50BMG to kill a deer. The light for weight TTSX/TSX's work. I also like the bone busting ability.

I like TTSX's north of 3200fps. Faster works even better. Just another dimension to the game.

A TSX of any flavor at 2800 doesn't excite me much.

FOr the 110's Think TAC would be a good powder to start with?

Yes it will penetrate, and Barnes says ya can get 3500+ fps with a 24" barrel and TAC, nearly 3600 FPS with AA-2230. LOL

Gunner

Kinda makes the 308 a different cartridge

Painfully different.

Gunner

Jordan/Gunner: That is precisely the theory behind the construction of the old Bitterroot.It ran contra to our conventional thoughts on how standard bullets behave,and how velocity affects them.

I spent a small fortune on phone calls to Idaho,and tested Bill Steigers patience explaining it to me 25+ years ago...until I finally got it,and saw it action a few times.

Geez,

There you guys go getting all practical and stuff...

3550fps from a 257wby+100ttsx= rapid death out to 500+

1st recovered X type in many years of using them.
.308 130 TTSX
MV 3050 with CFE 223
Front quartering shot on a whitetail at 70 yds. DRT.
Recovered on opposite flank in the hide.
94.6 grains retained

Center punched another through the lungs (same distance) a few seconds later. DRT

YRMV

thanks for the pic and the story...

how many have you killed with that combo?

where in GA do you hunt?