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View Full Version : Optimum alloy for subsonic hollow point rifle bullets?



The Lord Flashheart
10-31-2017, 05:35 AM
I finally have all the bits and pieces to begin casting the H&G Ness #38 safety bullet thanks in no small part to the kindness of Gamsek who without knowing me from Adam sent his MP version of the mould to cast bullets from. His kindness and assistance has left me speechless and mirrors the helpfulness of the membership more generally; this is a great forum and thank you all. :drinks:

Now, to the question...

I have gathered up ten pounds of pure lead and twenty pounds of linotype so far, melted, fluxed and cast into 1 and 1/2 pound ingots. I have been playing around with the Excel alloy calculator from the sticky and it seems that I need to buy some solder (60/40?) to be able to add tin for given recipes.

I want to shoot these hollowpoints at subsonic velocities and want them to expand as much as possible or to fragment completely, what would be the best alloy for that purpose?

I haven't decided whether massive expansion or fragmentation would serve my purpose better and so want to do some experiments on various media. I would then be grateful for suggestions as to alloys for both types of bullet.

The particular bullets are gas checked and I have 50/50 Alox/Beeswax and RCBS 8008 indoor lube.

Hickory
10-31-2017, 06:24 AM
This recipe has seemed to good for me for the Lyman #429640;
2% tin.
2% antimony
96% pure lead.

Disqualifying statement:
Although I have only shot 4 deer with this boolit, none traveled more then 8 feet after being hit. Expansion seemed good, but with only one recovered boolit that lost some of its hollow point, its hard to judge performance of the boolit, I can only relay results.

Larry Gibson
10-31-2017, 01:27 PM
Having cast and used numerous HP'd bullets at subsonic speeds I found a 40-1 lead tin alloy gives accuracy and best terminal effect. Any antimony will increase hardness and reduce the malleable property for best performance at subsonic velocity. The GC is very good to have.

hc18flyer
10-31-2017, 01:52 PM
Dumb question, what is speed of 'subsonic'? I am working with similar alloys for swc in my Ruger .45 Colt. Thanks, hc18flyer

Kosh75287
10-31-2017, 02:26 PM
The exact answer depends on air temp, humidity, elevation, phase of the moon, etc. I usually use "under 1070 f/s" as my definition of sub-sonic.

ADDENDUM:
If you use a 40:1 lead:tin alloy, your bullets may be too soft for velocities near 1070 f/s. If you are looking for something that might expand in the 700-850 f/s velocity range, the 40:1 alloy may work very well. Tin is often added not merely to harden the alloy, but also to assure that the molten alloy completely fills out the grooves and recesses of the bullet mould.

Whoever told you that adding antimony will harden the alloy is generally correct, but its other function is to make tin & other metal(loids) dissolve more uniformly into lead. It doesn't seem to take much to accomplish the latter task, without also getting the former result.

runfiverun
10-31-2017, 07:32 PM
40-1 will be fine.

OS OK
10-31-2017, 07:49 PM
10 lbs of Pb + 3.2 oz.(.2 lb.) Sn ... ='s ... 1.96% Sn & right @ 9.2 BHN (depending on just how soft your 'pure Pb' really is.)

"Makie big splat...big flat mushrooms that hang onto their weight."

fecmech
11-01-2017, 10:24 AM
Another vote for 40/1 lead tin.

Outpost75
11-01-2017, 11:13 AM
Another vote for 1:40 tin-lead.

Lacking that, a 1:5 linotype-lead blend at 8 BHN approximates the hardness of 1:40 alloy and is the frugal shooters best bang for the buck for general-purpose revolver, cowboy loads, black powder cartridge, and subsonic hollow-point hunting applications.

longbow
11-02-2017, 08:52 PM
Depends on which you want... expansion or disintegration. Ness wanted disintegration so used a hard alloy (seems to me he used linotype) that would shatter so no ricochets, just little tiny pieces.

I would post or send you the Ness article but have not loaded it back onto my hard drive after a PC meltdown. I should really get to reloading all the info I have on the back up hard drive.

Part of the rest of the story is that he designed to boolit as a blunt wadcutter so it would not travel very far before becoming unstable so reducing range should it be shot somewhat high and not fragment on the ground or a varmint relatively close. So if you are aiming high (varmint on a mound or hillside?) and miss the bullet has a relatively short range or if you hit the varmint or ground the boolit fragments.

I really have to reload that article and other stuff. Maybe this weekend. I'll post it or sent it when I find it.

Longbow

Forrest r
11-04-2017, 07:02 PM
The Ness bullet has a huge hp.
https://i.imgur.com/xVfJyoP.jpg

The is extremely long/deep, it extends to the top of the bottom drive band.
https://i.imgur.com/ZqOpZIV.jpg

It's pretty hard to get these bullets to mushroom + stay intact. I had only fair results with 10bhn alloy when driving these bullets in the +/- 1050fps range. Anything softer and the bullets just folded back or split badly. Anything harder and they fraged so I went with a bullet that fraged.

I tested several different alloys including several lead/tin alloys in mediums such as water jugs, bundles of tightly wrapped newspapers soaked for 24 hours in water, animals. Never could get any consistency with trying to get the hp's to expand like other/normal 30cal hp's that I either cast or hp using a forster hp tool. The soft hp alloy had a good smack to them, but there was huge differences in how the bullet performed when hitting a ground hog compared to a coyote. Now making the ness bullets frag was a heck of a lot easier and would consistently frag when they hit something.

Recovered pieces of the fraged bullets recovered from water filled milk jugs shot @ 50yds/1100fps. The bullets last drive band/base of the bullet always look like the one's in the picture below.
https://i.imgur.com/jaBlAYq.jpg

I like to run the ness bullets that frag in the 1600fps range. The holes they leave in wetpack @50yds/1600fps. The holes are 5" long and as big around as pictured below.
https://i.imgur.com/G77g8Sc.jpg

All's that's left of the bullet at those speeds is the last drive band/bullet base. That same load pictured above leaves fist sized holes in groundhogs and coyote's.

You might consider doing a 4 part lead/1 part mono-type and water drop them when casting. Start with bullets that frag then try/test soft alloys like 8 parts lead to 1 part mono-type for bullets that expand.

NYBushBro
11-13-2017, 11:22 AM
Fred Ness originally designed this to use for woodchuck hunting with a 30-06 in "suburban" areas circa 1940's - and used straight linotype specifically because it WOULD fragment, and not ricochet.

For other purposes and performance, a different alloy would be preferable.