TMJ vs "hard cast"

[ennis]

In the Spring I bought a few boxes of 10mm Remington UMC, 180gr Full Metal jacket. I got them for $22 per box of 50. The bullet is a cup and core construction and I was impressed with it's ability to penetrate without deforming. I needed a bullet for max penetration and strength, rather than expansion.  I recovered the bullet after shooting through a piece of 8x8. The jacket looked pretty thick and the bullet was unchanged.  I am curious how would this bullet compare to a 180gr, hard cast, lead bullet fired at the same velocity?  People are always recommending hard cast vs FMJ. What exactly is the benefit of hard cast vs a full metal jacket of the same weight?  Thanks for furthering my education.

[The_Shadow]

ennis, I think the main reason people go for the hard cast bullet is extra weight and wide nose profile to cut a larger deep hole when driven a the highest velocities possible.  Now my choice is for the Hornady 200XTP @ 1240 fps for the reasons listed above.

There's nothing wrong with using the FMJ/TMJ styles, but I feel if I'm hunting the HP design should bring about a cleaner more humane kill.  A SWC design cast bullet will probably cut a clean bore sized hole thru and thru.

In the real world, the cast bullets can be an afordable choice especially if your casting your own and wish to shoot a lot...

[sqlbullet]

Depends a lot on what is meant by "hard-cast" too.

Back in the Elmer Keith days 16:1 alloy was a hard cast alloy and has a BHN of about 11-12. A keith style SWC cast of 16:1 would expand some as it passed through a big critter.  But, it would also push through bones or dense tissue that might stop a soft lead bullet.

Today, hardcast often means straight linotype or some similar alloy, or a softer alloy that contains a grain refiner, usually antimony, that will heat treat to a stable, much higher hardness.  These are usually in the 22-26 range.  These bullets will usually not deform in tissue.  If they cannot hold together, they will shatter rather than deform.

I have a 205 grain WFN mold that drops bullets .402 that I use for 10mm.  I cast some up a few years back of water quenched isotope lead that had a BHN of 24.  Loaded over 12.5 grains of AA#9 these passed all the way through 11 one gallon milk jugs of water on a 6' long table.  the exit hole from the last jug indicated no expansion had occurred.  However, the nose of the bullet with it's wide sharp metplat was still cutting a .30" hole.

This then reinforces the point Shadow made about hard cast versus FMJ/TMJ.  Even a TMJ tends to have rounded edges at the nose and it doesn't make a clean crisp hole in plastic or tissue.  A round nose hard-case would behave the same.  But a WFN hardcast will give you wadcutter like crispness at it's metplat diameter.

Oh, and my 205 grain bullets cost me only time and I can cast about 500 in an hour.  Lots cheaper.

[Yondering]

  I am curious how would this bullet compare to a 180gr, hard cast, lead bullet fired at the same velocity?  People are always recommending hard cast vs FMJ. What exactly is the benefit of hard cast vs a full metal jacket of the same weight? 

FMJ has a hard shell but soft core; hard cast is hard all the way through. At the same velocity, a good hard cast bullet of a similar profile would penetrate about the same distance, also with very little deformation, unless bone or other hard objects are in the way, in which case the FMJ will sometimes deform where a hard cast can punch through.

Advantages of hard cast, as others said above, are a wider, sharper nose profile, and lower bore friction for higher velocity. If you cast your own, another advantage is being able to cast or heat treat them as soft or hard as you need. The same bullet can be made to act like a fragmenting hollow point, expanding soft point, or non-expanding penetrator.