expanding ammo

[THUNDERLORD]

It all depends on what you want to shoot with it.
In the original post you mention an "entry and exit hole" in tree.
Then I think you'd need a sabot.

Generally firearm hollow points don't perform as designed to below 1000fps.
Above around 1400 fps, there is a principal which comes into play that the object struck by the bullet turns into smaller bits becoming procectiles themselves and blowing holes much larger than the projectile with or without hp.
At even higher velocities the even soft point( sp) tend to desintegrate.

I watched a video on youtube of a guy shooting a combustion at a pumpkin w/ 6 golfballs and it disentegrated it nicely.
coincidently the same session I watched a guy shoot one with a 12 gauge and buckshot didn't have nearly the effect.(the energy of the buckshot was absorbed by the ground behind it)

At the same time, a little .22 hornet high velocity from a rifle probably has more stopping power than a .45 ACP round.

A little complicated and I think I'm kind of on borderline of breaking rules here. Just something to think about. 8)

[Tsukiten]

I once tried it and I have the solution!
(candle) wax!

Just sculpture the wax (should be a bit of a 'harder type', perhaps cool it for a sec?) in the desired shape and fire away!
Also a hollow-pointed candle wax slug works very well! Make a mold and drip (use a torch or something a bit stronger than a lighter) the candle wax bit by bit in the mold. Wait for a few min (perhaps more than half an hour), cuz if you don't there's gonna get still-liquid wax spoiled everywhere. If done right you now have a hollow-point candlewax slug.

Upon impact (hard material, not 'fleshy' target), it nicely expands like normal bullets do...but expect with some angled shots/too strong shots the slugs will simply shatter (and too slow shots will result in chunks breaking off)
I do not guarantee it works 100% (had some problems with mine too, try warming it up A LITTLE before firing) but it's a cheap way to do so.

[hyldgaard]

I once tried it and I have the solution!
(candle) wax!

Just sculpture the wax (should be a bit of a 'harder type', perhaps cool it for a sec?) in the desired shape and fire away!
Also a hollow-pointed candle wax slug works very well! Make a mold and drip (use a torch or something a bit stronger than a lighter) the candle wax bit by bit in the mold. Wait for a few min (perhaps more than half an hour), cuz if you don't there's gonna get still-liquid wax spoiled everywhere. If done right you now have a hollow-point candlewax slug.

Upon impact (hard material, not 'fleshy' target), it nicely expands like normal bullets do...but expect with some angled shots/too strong shots the slugs will simply shatter (and too slow shots will result in chunks breaking off)
I do not guarantee it works 100% (had some problems with mine too, try warming it up A LITTLE before firing) but it's a cheap way to do so.

I have experimented a bit with this in my pneumatic with pressures ranging from 4 to 20 bar, and i couldnt get any usefull out of it. The projectiles were way too light, so accuracy was pretty much non existing, and when it comes to deforming, i have never experienced this. i havent had one single shot with wax slugs without the slugs shattering in a 1000 pieces. Note that this is just in my pneumatic with limited pressure, i kinda doubt they will perform well in a 10X hybrid
Not trying to pick you down here, just sharing my point fo view

[Spuddin]

i've cast lead bullets for alot of years for my muzzleloader (round balls), pistols and rifles, your not going to have any luck with a huge heavy 2" lead slug, you need a much smaller barrel/bullet, i'd say no more than 1/2" to get any damage, the thing here is velocity, energy, and keeping the bullet from tumbling. i think your better off using the small barrel and a round ball which will tumble and thats fine, that should kill just about anything at close range or you could go with birdshot by using bb's.

[Gippeto]

If your goal is simply to blow a hole in a tree, with a small entrance and large exit, I will second the well proven round ball.

Or perhaps I should use the term canon ball? 2" is after all, quite substantial, and you really don't need it to expand.

Cast from lead, it should retain more than enough momentum to bust through.

It will not be a pretty or clean exit.

[Tsukiten]

I have experimented a bit with this in my pneumatic with pressures ranging from 4 to 20 bar, and i couldnt get any usefull out of it. The projectiles were way too light, so accuracy was pretty much non existing, and when it comes to deforming, i have never experienced this. i havent had one single shot with wax slugs without the slugs shattering in a 1000 pieces. Note that this is just in my pneumatic with limited pressure, i kinda doubt they will perform well in a 10X hybrid
Not trying to pick you down here, just sharing my point fo view

Yeah..No problem
My slugs were made of candle wax and slightly warmed up, so it's a bit softer...
Someone ever tried some of the softer wax like hair wax or vasaline-like stuff? (petrolium jelly)

[SpudFarm]

"gippeto: it is mostly to find a nicely expanded 2" bullet and place under my pillow (spelled right)?

and for all others the goal is not to get through the tree i can do that with a solid steel slug but fresh wood makes things expand..

my goal it to order some custom bullets for armor piercing from Larda and shoot them in the front of a car through the engine block and out the back "optimist

[judgment_arms]

At the same time, a little .22 hornet high velocity from a rifle probably has more stopping power than a .45 ACP round.

Okay .45ACP ballistics:
Fastest: 165gr JHP, 1060FPS 412ft-lb
Strongest: 230gr Hydra-Shok JHP, 900fps, 414ft-lb

.22 hornet:
Fastest: 35gr, 3060fps, 728 ft-lb
Strongest: 55gr, 2652fps, 859ft-lb

Well of course the .22 hornet’s stronger, it’s a rifle round after all.

If you want holes use low mass high velocity rounds, if you want raw power there’s no substitute for cubic inches.

Remember, it’s not how fast the lead is going, it how much lead is going.

EDIT:
I type to slow…
If you want to go all the way through you need a solid chunk of steel… or something that looks like an RPG-7 rocket, basically have a solid chunk of steel on the end of rod, and the other end have short fold out blades to tear through the steel.

[iknowmy3tables]

so how about a steal core like in AP rounds with in all the lead, hollow tips alone are useless for armor penetration,
http://world.guns.ru/ammo/bullets-e.htm#fmj

[Blitz]

What you need is a shaped-charge warhead. j/k.

And right, hollow points aren't even designed to penetrate, they're specifically designed to minimize penetration and maximize tissue damage.

Hard cores would work well. Once the external part of the projectile is stripped away, the hardened core would continue to penetrate its target.

Man, I remind myself of Mack from Futureweapons, with the amount of times I've mentioned "penetration."

[SpudFarm]

so how about a steal core like in AP rounds with in all the lead, hollow tips alone are useless for armor penetration,
http://world.guns.ru/ammo/bullets-e.htm#fmj

i said i will use a expanding round just to make one, and to have one standing on a shelf..
then i said that i can get solide steel slugs from Larda...

[THUNDERLORD]

Ah Umm....What he said

If you want holes use low mass high velocity rounds, if you want raw power there’s no substitute for cubic inches.

@the Judge,
Thanks for clarifying and the ballistics info, that's interesting.

I think as far as spud type technology, I agree definately (or go with some kind of strafer type contraption)

EDIT:OOops, Just read over that and i think low diameter but not lower mass for spud type technology, I'd go with higher mass and smaller diameter similar to blow gun dart or arrow for greater penetration at low velocity.

[Gippeto]

An expanding round just to have it. Hmmm.

Well how about an aluminum tube (~1-2mm wall?), filled with a mix of wax and lead shot.

Anneal the aluminum first, then add wax and shot, let cool, cut the slits.

Slit the sides of the tube from 1/3 length to the front in 5 to 8 places.

Even at typical spudgun velocity's it should expand. (IF it hits front first, which will be the hardest part)

[SpudFarm]

(IF it hits front first, which will be the hardest part)
point blank

[sniper hero]

A few days ago I tried to make some expanding ammo and it's hrder than I thought
I made a kind of dum-dum bullet from a piece pipe filled with hot glue
didn't work it had very good damage
I also tried a kind of bullet made of four oieces but they just penetrated independently