Bullet Performance Database

[Gomer]

I have never seen a partition seperate as pictured. Front separation yes but rear section never.

I’ve lost the rear lead core a couple of times with 210gr Partitions fired out of a 338. All i recovered was a mushroomed front with a hollow rear jacket.

 

[Daryl S]

Wondering if those 210's have a shorter back section compared to other weights.
Turning around after losing the front and expanding the opening might have that effect.

 

[MS 9x56]

Bullet tumbling?

 

[Daryl S]

Yeah, they do that, turning bass-ack-wards - sometimes. Have you never seen that, at least in GEL. tests?
The shorter the bullet becomes (it appears), the less stable it becomes in it's traverse through the animal and the more likely it will turn butt first.
Some bullets do that right away, if the ROT is on the slow spectrum for that length of bullet.
That happened most dramatically in Viet Nam, with the 55gr. FMJ's in a 12" ROT of the M16's.
It also happens to bullets losing too much length through sloughing off weight when penetrating in animals. It is likely this would not happen, EVER, with a .338", 225gr. or 250gr. bullet.
My long time friend (since 1972)and guide Igor, noted the fastest kills he had witnessed on Grizzlies was by a 225gr. .338 Win. Mag with the 225gr. Nosler, BANG/FLOP, DRT.

 

[TTundra]

I’ve lost the rear lead core a couple of times with 210gr Partitions fired out of a 338. All i recovered was a mushroomed front with a hollow rear jacket.

375 nosler partition separation, nose amd core. Found it laying sideways on the wildebeest.

 

[Daryl S]

WOW, I've not seen that before. Tks for the pictures.
You can see thr crimped base is expanded but the front end not.

 

[SkullKeeper]

Does anyone know the relative expansion difference between Swift A-frame and the equivalent North Fork? I ask because I believe the common wisdom is that the North Fork will penetrate further. So, I am wondering if the Swift frontal diameter is actually more

One thing of note and notice: most recovered A Frames have a swollen rear area directly under (behind) the copper bridge in the bullets center. This comes from the pressure exerted on the front half of the bullet by the rear section during penetration- the bullet is in essence loosing forward motion/energy by working against itself. A North Fork having a solid copper base will not shed energy this way. In theory the North Fork should penetrate farther than an A Frame grain weight for grain weight and given rate of expansion is equivalent.
On another point I’ve seen brought up here, there’s talk about lowering velocity to achieve better penetration as a result of lesser expansion. You have to keep in mind that the greater the velocity the larger the cavitation bubble. It’s somewhat of a double edged sword but personally I’ll take the higher velocity and greater expansion/larger cavitation bubble if I’m choosing to shoot soft nose bullets.

 

[Twraska]

One thing of note and notice: most recovered A Frames have a swollen rear area directly under (behind) the copper bridge in the bullets center. This comes from the pressure exerted on the front half of the bullet by the rear section during penetration- the bullet is in essence loosing forward motion/energy by working against itself. A North Fork having a solid copper base will not shed energy this way. In theory the North Fork should penetrate farther than an A Frame grain weight for grain weight and given rate of expansion is equivalent.
On another point I’ve seen brought up here, there’s talk about lowering velocity to achieve better penetration as a result of lesser expansion. You have to keep in mind that the greater the velocity the larger the cavitation bubble. It’s somewhat of a double edged sword but personally I’ll take the higher velocity and greater expansion/larger cavitation bubble if I’m choosing to shoot soft nose bullets.

I disagree with your first comment. Weight is weight and as long as the bulge doesn’t expand past the front, it don’t matter. The back is essentially in a void as it passes.

 

[Olivier]

Recovered .308 Win bullets from a wild boar shot at close range with a Tikka CTR (20" barrel).

• Left: Barnes TTSX 168 gr
• Right: Norma Tipstrike 170 gr

 

[SkullKeeper]

I disagree with your first comment. Weight is weight and as long as the bulge doesn’t expand past the front, it don’t matter. The back is essentially in a void as it passes.

My point with the bulge is that energy is flowing outward at a 90 degree angle instead of in a straight line forward. No worries though, as the energy lost is of virtually no significance.

 

[SRvet]

Recently back from Namibia where I shot a buffalo bull, a hippo and a giraffe all for management purposes. The buffalo and the giraffe were shot using my 458 Lott and 450 grain Barnes TSX and the hippo was shot using the 300 grain TSX from my .375. Expansion was excellent on all recovered bullets. The 300 grain TSX.375 lost the most mass due to hitting solid bone. I am very satisfied with the performance of these bullets.

 

[MS 9x56]

Yeah, they do that, turning bass-ack-wards - sometimes. Have you never seen that, at least in GEL. tests?
The shorter the bullet becomes (it appears), the less stable it becomes in it's traverse through the animal and the more likely it will turn butt first.
Some bullets do that right away, if the ROT is on the slow spectrum for that length of bullet.
That happened most dramatically in Viet Nam, with the 55gr. FMJ's in a 12" ROT of the M16's.
It also happens to bullets losing too much length through sloughing off weight when penetrating in animals. It is likely this would not happen, EVER, with a .338", 225gr. or 250gr. bullet.
My long time friend (since 1972)and guide Igor, noted the fastest kills he had witnessed on Grizzlies was by a 225gr. .338 Win. Mag with the 225gr. Nosler, BANG/FLOP, DRT.

Can’t say I have ever seen the rear seperate.

 

[Daryl S]

Didn't say separate. The rear core coming out is what was reported and pictured. I've not seen it personally, but obviously happened.

 

[MS 9x56]

I have seen bullets tumble in game and in some soft bullets with exposed lead tips the core seperate from the jacket. Those African animals must be some kind of tough.

 

[Rule 303]

My point with the bulge is that energy is flowing outward at a 90 degree angle instead of in a straight line forward. No worries though, as the energy lost is of virtually no significance.

Is the energy directed outward or forward. To my mind the rear of the bullet is pushing the front forward. Take the 6.5 that Bell used for a short period on elephants. The bullet bent in the middle and the base ended up trying to catch the nose. Bell's description from memory. The jacket been to thin for such a long round and the bullet bending in the middle. The bulk of the energy was still spent in the forward direction

 

[SkullKeeper]

Is the energy directed outward or forward. To my mind the rear of the bullet is pushing the front forward. Take the 6.5 that Bell used for a short period on elephants. The bullet bent in the middle and the base ended up trying to catch the nose. Bell's description from memory. The jacket been to thin for such a long round and the bullet bending in the middle. The bulk of the energy was still spent in the forward direction

There’s no doubt that the rear end of the bullet is pushing the front end forward as a single unit BUT upon impact with substance “X” there is a momentum change between the now two distinct parts due to its lack of complete structural rigidity and the rear half now travels faster than the front half hence forming the “bulge” (energy displacement at a net 90 degree angle from straight line momentum). A good example of this is when a car rear ends another - the vehicle in the back is traveling faster than the vehicle in front and energy is shed in multiple directions including, but not 100%, forward. This definitely accounts for, as you mentioned in reference to Bell’s bent bullet, the bulk of the energy spent in a forward direction.
It’s a neat little physics lesson and fun to contemplate but it’s really all for naught as they say! Cheers everyone!

 

[Daryl S]

Technically yes. What I have seen, is that the Swift A-Frames appear to now outperform Nosler's Partition bullets, both in penetration and outward expansion.
The Noslers appear to most often lose the front end entirely with the front "petals" closely folding against the shanks, whereas the Swifts appear to expand very nicely.

 

[Twraska]

My point with the bulge is that energy is flowing outward at a 90 degree angle instead of in a straight line forward. No worries though, as the energy lost is of virtually no significance.

Ok, I ‘see’ what you are talking about now. The bullet is using energy to deform.

 

[Daryl S]

I do not see the way Swift bullets deform as being a negative, do you? All bullets use energy to deformation, if constructed to do so. Once energy is used, it is gone, ie: used up. If that projectile still penetrates and destroys the necessary tissues, the expansion/appearance of the rear shank is meaningless -does not matter. The fact they have a GREAT following AND reputation should negate anything negative someone might find about their appearance, IMHO.
I've never used them, but would if my regular cup and core bullets didn't perform for me.

 

[SkullKeeper]

I do not see the way Swift bullets deform as being a negative, do you? All bullets use energy to deformation, if constructed to do so. Once energy is used, it is gone, ie: used up. If that projectile still penetrates and destroys the necessary tissues, the expansion/appearance of the rear shank is meaningless -does not matter. The fact they have a GREAT following AND reputation should negate anything negative someone might find about their appearance, IMHO.
I've never used them, but would if my regular cup and core bullets didn't perform for me.

Absolutely no negative about them at all, only observation. I’ve recovered some bullets from African game that were atrocious to look at - but they were recovered meaning dead animal. All’s well that ends well!