This post is the introduction to a firing test to be carried-out within a week. I'm pretty confident of the timing, since most of the ammo is loaded, the recovery box is complete, and the 'stopping medium' is identified and available.
This is purely a test to see how my cast softpoints compare for terminal expansion with a bullet whose performance I know intimately ON GAME ANIMALS. This "control" bullet is the .30-caliber 180-grain Nosler Partition, and it will be fired into the box at 2500 fps to represent the impact velocity from a .300 or .30-06 at some distance off the muzzle. Comparing how it looks from the box, to how it looked when recovered from moose and caribou, should give me an inkling of how well or poorly the cast softpoints will fare against animals. Bullshop's recent experience on a moose with a 50/50 (soft/hard) softpoint is also an invaluable clue (it was AWESOME!).
ALL the bullets to be tested are built on a 1/3-soft to 2/3-WW (harder) formula, and all are aircooled from the mould. This is subject to assessment and change if needed, but I believe it's close to the right proportions.
The loads are picked to reflect realistic field impact speeds, although in the case of the .416 Rigby I have loaded both a muzzle-velocity-impact test (365@2050 fps) AND a lower-speed test at 1700 fps to see how a bit of distance might affect things.
Right now, the list to be tested includes:
-311299 at 1800 fps
-.338-220 LEE at 1800 fps, with several identical rounds to test the consistency of the expansion
-.416-365 RCBS at 2050 fps, several rounds to check consistency as in .338 above
-.416-365 at 1700 fps
-.459 LEE 420-grain hollow-base at 1500 fps (my chosen max speed for the Shiloh .45-70 in most of my shooting)
-.459 SAECO #021GC spirepoint, 420 grains at 1500 fps for the same reason. I'm very curious to see how the spirepoint will upset, compared to the round-nosed Lee bullet. The lower velocity may prove interesting vis-a-vis expansion or not, as well.
If time permits, I may expand this list a bit....I'd like to fire the .45-70s at 1800 or so just for all you Marlin .45-70 fans, for one thing. Perhaps some water-quenched softpoints for direct comparison may be added, if I can find time to cast a few.
The speeds above were chosen to reflect the impact speed at practical ranges. The .30 and .338 are very likely to be loaded for CAST-BULLET hunting at muzzle velocities over 2000 fps, so 1800 fps should show what the bullet will do from 100 yards or so.
Now, the test:
The recovery box is made of plywood on a frame of 1x2 lumber, glued- and screwed-together with drywall screws no more than about four inches apart on all seams. It's one foot square and five feet long. The 'entry' port has a six-inch circular opening which is covered with a sheet of 1/4" gum rubber sheeting, which should be capable of sealing-up so tightly after bullet passage that no leakage will occur. The back end of the box has a 1-inch-thick pad of the same material, which should stop anything getting that far with considerable gentleness and no damage (I don't think any bullet will reach this rubber). All seams are heavily caulked inside the box with 100% silicone.
After seeing the explosive effect of the .416 softpoints on water jugs in an earlier test, I have no intention of tightly sealing the plywood lid. Instead, the lid is mounted with eight carriage bolts with their heads INSIDE the box, and the nuts and washers above the lid arranged to allow the lid at least one inch of free travel upwards. I hope this will allow sufficient pressure release while minimizing the loss of the stopping medium.
Ah, yes: the stopping medium, and the reason for "inscrutable" in the title....the stopping medium is a RICE SLURRY!
Reasons:
-rice is absolutely consistent, from batch to batch, and thus any additional tests can be considered to be comparable to this one. Also, it is AVAILABLE, even in small-town Nevada.
-in slurry form with enough water to just form a layer on top of the expanded rice, there will be no cavities left in the medium after the passage of each bullet. The slurry will fill in any temporary cavity and the bullet will just sink to somewhere below its ballistic trajectory. The following bullets will positively not encounter any voids in the medium. This is NOT the case in such things as wetpack newsprint, for example.
-testing has already shown that even in cold water, the rice is fully 'hydrated' and expanded after three hours of soaking. I will have a reserve supply of already-expanded rice on hand to replace whatever gets blown out of the box by bullets....and I'll fire the heaviest-hitting rounds last, just in case.
-all I'm asking is that my medium should present more resistance to bullet passage than plain water, and the rice will surely do that. Other possible materials considered were spuds and pinto beans, but rice is a good bit less-expensive. Even so, I'm figuring on needing at least 80 pounds of rice, which comes to about $34, plus maybe $40 for the box ....this isn't gonna be a cheap bullet test! The box will weigh around 400 pounds when ready for tests. It'll sit on the tailgate of my pickup for the shooting.
IMPORTANT: I am NOT saying that this is a realistic test to determine what my softpoint bullets will look like after encountering an animal! This is an exercise to see how MY bullets compare in a known medium to a superb game bullet, the performance of which is well-known and familiar to me, personally. Please don't try to draw conclusions here about my motives or relative sanity....please. (I already KNOW I'm a terminal nut-case, and don't really need the reminders. I just do what the loudest voice in my head tells me...)
Stay tuned for updates.
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Originally Posted by BruceB
