FPS needed To expand cast boolits

[JTknives]

I have often wondered what velocity is needed to reliably expand cast boolits. I know hardness and meplat size plays a part. But looking at rifle bullets for my 30-40, I was given some 247gr NOE 30 cals and wondering how fast I would need to push them to get them to expand in game.

[Petrol & Powder]

Expansion is the icing on the cake. If you achieve expansion, great but adequate penetration is the first hurdle you most clear. While it is true that a bullet that passes all the way through its target doesn't impart all of its energy to the target, it does make two holes with lots of damage in between.

I totally agree with Nise, that question is too vague to answer and there are a LOT of variables. Alloy, velocity at impact, WHAT it impacts, bullet shape, etc.

[btroj]

This is like asking a knife maker how sharp a knife is.

A soft HP can expand at 800 fps, a sharper nosed solid may need 1500 or more.

You also need to ask if you really need expansion.

[JTknives]

I guess I'm asking is this. Will a 160-250gr boolit cast from WW and just air cooled with a small .0625 - .125 meplat going 2000-2300 fps expand in game animals well enough to hunt with. What has your experience been with hunting with cast rifle boolits?

[btroj]

I would go with a slightly softer alloy and water drop. Wheel weights/lead 50/50 will water drop or heat treat to a BHn that will alloy those speeds. The alloy will also allow some expansion to occur.
You could also do worse than the BruceB method of making soft points. Those will expand well but with a harder base portion you are assured of good penetration too.

[TXGunNut]

I suspect this boolit's strong suit is penetration, not expansion. Not saying it won't expand because that's hard to say. Some testing will tell you more than I ever could. I like a bigger caliber boolit and a big meplat for killing the critters I hunt but I see no reason why the boolit you describe wouldn't work. I don't think 2300 fps would be necessary for expansion or decisive kills but again, testing will tell the tale.

[Forrest r]

The size/shape depth of the hp plays a huge part in how it will perform. Small hp's or shallow cupped hp's do better @ higher velocities while larger and deeper hp's do better @ lower velocities.

One of Ben's bullets, Ben writes excellent threads on this forum & he's always showing tidbits like these.

http://i162.photobucket.com/albums/t242/forrestr-photo/357amp38hp_zpsertllrda.jpg (http://s162.photobucket.com/user/forrestr-photo/media/357amp38hp_zpsertllrda.jpg.html)

Some 44cal bullets cast with different sized/shaped/depth hp's that are designed to perform at different speeds.

http://i162.photobucket.com/albums/t242/forrestr-photo/customkeith44_zpsad8bf656.jpg (http://s162.photobucket.com/user/forrestr-photo/media/customkeith44_zpsad8bf656.jpg.html)

Done limited testing with rifle/cast/hp bullets and planned on hp'ing 2 different molds this summer for a 308 and doing testing with several different shaped hp pins (4 each) for the same mold. Along with testing the 3 hp molds I already have for the 30cals. The issues I encountered in the past were alloy related. Faster bullet speeds ='d harder/brittle alloys that didn't perform very well for hp's. Allot of casters make a type of 2-piece bullet with the drive bands being 1 alloy and the bullet nose being another/softer alloy.

I began the groundwork this last summer plinking/testing pc'd bullets in the 30cal's. I wanted to see how fast they could be driven and still stay intact. It turned out that cast bullets made from nothing more than range scrap/berm picking that were pc'd and nothing more than air cooled produced an extremely soft alloy (good for hp's) that cold be driven @ fairly high speeds/high pressures.

http://i162.photobucket.com/albums/t242/forrestr-photo/shotboolits_zps66df2631.jpg (http://s162.photobucket.com/user/forrestr-photo/media/shotboolits_zps66df2631.jpg.html)

As you can see, the bullets bend, they don't break or shatter. The 2300fps bullet is a 230g bullet that was shot from a 308 with 37g of bl-c2 putting that load in the 48,000psi range. With the alloy issue taken out of play that only leaves the design/shape/depth of the hp.

[Larry Gibson]

My experience since '68 shooting numerous deer, feral goats, pigs a couple elk with the 311041 in various cartridges is that I prefer a softer alloy and an impact velocity of 1400 - 1500 fps. I most often these days us COWWs +2% tin and then mixed 50/50 with lead. These bullets are AC'd and aged for a minimum of 10 days. I also HP the nose to 3/16" deep with a modified HP stem or with the Forster 1/8" HP tool. Depending on rifle and cartridge a muzzle velocity of 1950 - 2200 fps is needed for a 150 - 200 yard maximum range. With such bullets I get complete penetration on broadside and most quartering shots with heart/lung shots. The wound channels have always exhibited good expansion with little to no petal sloughing.

That is my experience and preference based on my experience.

Larry Gibson

[MBTcustom]

Follow the link in my signature line.
Cast bullets can have way more effect than you bargain for!

[fredj338]

I would say it is likely to deform, but not truly expand, unless impact vel stays up there. To get it running over 2000fps with accuracy will probably require a tougher alloy that will not allow for any expansion w/o a HP of some kind.

[Outpost75]

American Rifleman published some articles by Ed Harris with results using cast bullets for deer hunting back in the early 1980s. As I remember he was using wheelweights +2% tin in the. 30-'06 at velocities around 1800 fps with #31141 and RCBS 30-180FN. I use similar loads about 30 grains of 4895, 4064, RL15 or Varget in the. 303 British with #314299 and these charges would be safe in a sound Krag.

[quilbilly]

In my 308, a 163 gr RNGC expands to over .6" at an MV of 1900 fps and 40 yards (Penetration in wet phone compacted books is 18"). The alloy is slightly softer than ww.

[Forrest r]

My experience since '68 shooting numerous deer, feral goats, pigs a couple elk with the 311041 in various cartridges is that I prefer a softer alloy and an impact velocity of 1400 - 1500 fps. I most often these days us COWWs +2% tin and then mixed 50/50 with lead. These bullets are AC'd and aged for a minimum of 10 days. I also HP the nose to 3/16" deep with a modified HP stem or with the Forster 1/8" HP tool. Depending on rifle and cartridge a muzzle velocity of 1950 - 2200 fps is needed for a 150 - 200 yard maximum range. With such bullets I get complete penetration on broadside and most quartering shots with heart/lung shots. The wound channels have always exhibited good expansion with little to no petal sloughing.

That is my experience and preference based on my experience.

Larry Gibson

Thank you for that!!!

The 3/16th's 1/8" hp sounds like an excellent place to start.

[btroj]

American Rifleman published some articles by Ed Harris with results using cast bullets for deer hunting back in the early 1980s. As I remember he was using wheelweights +2% tin in the. 30-'06 at velocities around 1800 fps with #31141 and RCBS 30-180FN. I use similar loads about 30 grains of 4895, 4064, RL15 or Varget in the. 303 British with #314299 and these charges would be safe in a sound Krag.

This. That Ed Harris guy is pretty smart.

[Blackwater]

There are many variables at work when we try to determine how a given bullet will perform on game. Best thing to do is go get some pasteboard boxes and some newsprint, tie bundles of newsprint up real tight with strong twine, put them in garbage bags, and place inside the boxes, trying to get the boxes full and tight, then fill with water and let them soak for a good 45 min. before shooting them. It'll simulate flesh fairly well, though in my experience it'll allow a bit more penetration than real flesh, and it won't expand bullets quite as fast as real flesh, but it's close enough to get a good idea of what it'll do on game with your alloy at your velocities. You can get several shots in those boxes before needing to go to another box for further experimentation. Doesn't really take all that long, and it's about as definitive as you'll probably need to be.