Cast bullet design for subsonic hunting

[Jamtrails]

Does anyone have experience with deep hollow points on 30 cal bullets?

[Bigslug]

Welcome!

Ummm. . .not exactly hollowpoints and not exactly .30 cal, but maybe as a decent reference for approximate diameter, shape and material?

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These are .320" diameter 130 grain WFN's that were both shot into gallon jugs from about ten yards at 1250 fps. Only difference was the alloy. The hard one on the left (water quenched wheelweight, as I recall) stopped in the ninth jug in the stack. The expanded bullet was 20-1 lead/tin and it stopping in four.

What are you trying to accomplish?

[Jamtrails]

Thanks for the welcome!

What I'm trying to accomplish is reliable expansion with deep penetration for a subsonic hunting load for big game.

I was toying with the idea of getting a .458socom after getting poor results with copper subsonic bullets and thought that before I spent all that money, ID try to find a solution in .30 cal.

So my idea is to get a mould made up for a bullet with a very deep, possibly notched hollow point, maybe a boat tail that comes in around the 230 to 240 grain mark.

That should guarantee enough bullet for half to expand and half to remain. So far Ive learned that the mix to go for is pure lead with 5% tin.

My casting experience is limited to some black powder bullets for .45-120 many years ago but I really enjoyed it.

[BLAHUT]

Just go with big in pure lead, don't need a hollow point.

[Jlwilliams]

I'm also a bit disappointed in 300blk subsonic for hunting. I think it's just the nature of slow bullets. I'm leaning toward going bigger. 30 caliber just doesn't do it at low velocity.

[fastdadio]

I launch my 170gr, .30 cal. boolits from my 30-30 at about 1850 fps. They must be subsonic on the front end, because all the deer I've shot with them never heard them coming. :kidding:

[GhostHawk]

Agree that large caliber and a large meplat will work better for penetration and opening a large bleeding wound channel than a HP at slow speeds.

What your asking for is somewhat of a contradiction in terms.

Increasing the caliber size increases the size of your hole without expansion.
WFN or large meplat again rips a big hole and expansion not required.
Slow speeds work fine.

[ChristopherO]

Lead boollits and boat tails are not a natural combination. Everything I've learned is that the base must be uniform and full size to prevent gas blowby from cutting the lead to achieve consistent accuracy. One would think a boat tail will deform from gas jetting.

[Harter66]

Enter the .312-230 RG NOE , or not .
Most any 200gr selection cast 10 bhn will expand inside 50 yd. Some pure subs will be a little more challenging.

[Winger Ed.]

Sometimes slow hollow points get plugged going in, or collapse shut.

Check out pictures of the ammo used for big bore, dangerous game rifles like the Nitro Express calibers:
If you look at the bullets used for serious killing, most are round nose, or flat points.

As you go slower, you're also giving up range and penetration.
For hunting big game, that sounds like a bad combination.

[megasupermagnum]

You will never get to the level of the 45 caliber, but a 30 caliber subsonic can work fine for hunting medium game. The most detailed studies in this area have been done with air guns. That is with 150-160gr bullets, and they mostly top out in the 850 fps range. Heavier bullets will help in a firearm, but there is a practical limit. You will not find a mold maker who will make a 230+ gr HP 30 cal. That bullet would be insanely long, too big for mold blocks. A 240 gr solid is as big as I've ever seen.

Due to practical design limits, I would look into 180 to 215 gr hollowpoint flat base molds. A gas check mold wouldn't hurt either. For lead alloy, 20-1 is as hard as I would try. 40-1 or even pure lead would be very good

[Bigslug]

I'm guessing you're running a Blackout?

Weight of your bullet is going to be determined by what shape fits your cartridge neck, magazine, and chamber throat. The first two are pretty easy math. The third will probably require a pound cast of your chamber (there's threads here on how to do this). As posted by another, boat tails aren't really a cast-bullet-friendly article. If you're running an AR-based autoloader, you'll need to shape the nose for the feed ramps, and have the bullet be hard enough to withstand the trip up and over it.

A good subsonic launch speed would be to follow the lead of .22 match ammo at about 1080 fps. That's roughly what you'll get out of a 147 grain 9mm duty load out of a 16" carbine barrel. I guess another reference may be in order:

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That's a 135 grain 9mm NOE/Ranch Dog tumble lube WFN style of wheelweight alloy out of a Glock at 1030 fps that stopped after nine milk jugs (almost made it into ten). For comparison, most police duty auto loads will stop in 3-4.

The real problem with expansion in this low-intensity performance envelope (as I see it) is that you need some assurance that it will still expand AT THE VELOCITY/RANGE IT IMPACTS AT. Police duty loads are easy - how much of that takes place past 50 yards? Really, even past 20 yards? The beauty of a flat-nosed solid of heavy-for -caliber weight is that it will usually keep on truckin' through across a wide range of speed. The tissue disruption may not be quite on a level of an expanding bullet (which at subsonic speeds won't be anything spectacular anyway), but it will be more predictable regardless of range and penetration won't be compromised by the bullet turning into a parachute.

I'd be inclined to work out the most aggressive meplat that will feed in the gun in a tumble-lubed, gas-checked solid and cast it on the hard side. It'll never equal the .34" meplat of a .45 caliber WFN, but regardless, game animals taking a pass-through the heart and lungs traditionally tend to die pretty quickly. If the gun won't feed a wider nose, you'll probably want to add certainty by trying to break the far-side shoulder.

[Barry54]

Thanks for the welcome!

What I'm trying to accomplish is reliable expansion with deep penetration for a subsonic hunting load for big game.

I was toying with the idea of getting a .458socom after getting poor results with copper subsonic bullets and thought that before I spent all that money, ID try to find a solution in .30 cal.

So my idea is to get a mould made up for a bullet with a very deep, possibly notched hollow point, maybe a boat tail that comes in around the 230 to 240 grain mark.

That should guarantee enough bullet for half to expand and half to remain. So far Ive learned that the mix to go for is pure lead with 5% tin.

My casting experience is limited to some black powder bullets for .45-120 many years ago but I really enjoyed it.

https://www.bearcreekarsenal.com/458-socom-16-parkerized-hb-1-14-twist-carbine.html

The cost of brass is where they get you...

[stubshaft]

I used to shoot the Lee 230 gr. 30 cal. out of my 7.62X39 (.308" bore) and it anchored a couple of hogs and a slew of feral goats with no problem. No expansion but the tumbling just tore the cr@p out of the innerds.

[Milky Duck]

rightho folks...time for some HOME TRUTHS....
this is something I can answer honestly as had a really good play with it.
there is an awesome 151grn mold out there. we can buy the cast projectiles for very little cost,guy in Tokoroa makes them.
it has a large hollow point,if the hp bit isnt fitted it makes a 170grn flatpoint.
both will go through a red deer at subsonic velocity...yes thats not a misprint,both will go in,and exit a 120lb deer or a 50 lb goat with ease.
I loaded up all sorts with these and used them to headshoot my own sheep for house muttons... ranges between 25-75 yards.
if my shot was spot on and hit brain or spinal column it was lights out,BUT a tiny miss of bone resulted in a angry animal with light headache... shot in same place with supersonic round and its lights out.... I only recoverd one projectile,it measured 13mm across..will try to find photo.
you are much much much better off to load projectile at 1200-1500fps you will get much much much more reliable killing power and guaranteed expansion.
you can improve expansion by inserting either a steel #BB or even a plastic one in nose cavity and glue it in place,3-4 slits down into the lips of the nose will also make it expand faster.
I shot a few rabbits with these loads...great but if you hit a stone/rock holy smoke do they bounce ricochet off into distance...

[Milky Duck]

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[Milky Duck]

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[barrabruce]

Thankyou milky duck I will keep that in mind.
I have a 150 hp hunter that shoots o.k.
My nose could be a smidgon fatter.
I will try something stuck into the nose and see if they expand.

[quilbilly]

I used to shoot the Lee 230 gr. 30 cal. out of my 7.62X39 (.308" bore) and it anchored a couple of hogs and a slew of feral goats with no problem. No expansion but the tumbling just tore the cr@p out of the innerds.
That is what I saw in my own terminal ballistics tests using low velocity RN 160's from a 30/30 at 40 yards into soaked compressed phone books. Of all the calibers and loads I tested over several years, those tumbling 30's made the most impressive wound channels. That being said, my new Henry 45LC lever gun launching soft lead 265 WF's at 1070 fps would be much better. With all that extra momentum, it would pass through like butter and drop the second deer behind your target. BTW - Welcome to our very knowledgable group.

[Elmer Fudd]

I have had several experiences to share.
A mid-weight 35 and less caliber cast soft will expand, or rivet. That can be good because it makes a larger wound channel.
A soft HP, same mid-weight (or even heavier) 35 and less caliber will expand like the dickens, even around 850 fps, which even gooder and makes an even larger wound channel.
And a harder (I haven't used type-metal, but BHN 12 to say 18 - quenched COWW) HP will shed the front pieces like a mono-metal bullet such as a Hammer and still penetrate like mad. The front of the separated bullet ends up a lot like the design of the SSK cavities, I am sure by no coincidence on SSK's part.
Some expansion can be a good thing, some weight loss can (and often is) a great thing. But I will return to: bullet placement and hitting something that can leak or knock the brain out is the critical part. A .35 soft spire point cast from a Whelen into the liver won't be a great experience for anyone compared to using the same and hitting big nerve bundles or the spine. Cases can be made for lung shots and even for heart shots, both of which are almost always lethal, though you can get dead runs that go surprisingly far with either. I eat heart, so I avoid shooting them, especially with fast bullets (bruising doesn't go in my frying pan). I don't eat liver, but I don't usually shoot them because the guts are so close. I do keep a soft cast or a Speer Plinker handy for shooting said livers once removed from the carcass; softer is better for that!