Expansion of bullets in a Subsonic cartridge.

Discussion about rifles in 300 AAC BLACKOUT (7.62x35mm), hosted by the creator of the cartridge.

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Oneguyzopinion
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Expansion of bullets in a Subsonic cartridge.

Post by Oneguyzopinion » Thu Jan 19, 2023 8:56 pm

Has anyone been able to get expansion data on hunting projectiles from a specific manufacturer?
Specifically, what does the expansion of a Hornady Interlock (SP)150 gr loaded to be fired at 1045 ft/sec look like?
You can see pictures of them but they only sometimes tell you the velocity and even then it’s never at a subsonic velocity.
Ideas? I want to take a 16 inch bolt action (Suppressed) hunting for Javelina. I’d sure like to know or at least think I know what to expect before I go shooting at live game.

I emailed Hornady but on this issue, they haven’t gotten back to me yet.

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BJK
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Re: Expansion of bullets in a Subsonic cartridge.

Post by BJK » Fri Jan 20, 2023 12:11 am

Have you checked youtube? I'm not saying it's there, but if it's not here (in a search) that's the next place I'd check.

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dellet
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Re: Expansion of bullets in a Subsonic cartridge.

Post by dellet » Fri Jan 20, 2023 7:12 am

Expect absolutely no expansion from that bullet at that velocity. The lower limit will be around 1800 fps.

Unless specifically designed for subsonic expansion, most .308 diameter bullets can be expected to expand down to around 1800 fps. If designed for use in a 30-30 around 1600 fps. 300 Blackout 1300 fps.

Look at Maker bullets, he has some lighter expanding subsonic bullets. But honestly a 150 subsonic for javelina is a bit light. Unless you’re really close, or they are really small.
300 Blackout, not just for sub-sonics.

Oneguyzopinion
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Re: Expansion of bullets in a Subsonic cartridge.

Post by Oneguyzopinion » Fri Jan 20, 2023 9:35 pm

Excellent info. Thank you.
Where do you get this info? A reference source or just field experience?

I like to do my own research when possible.

Again, though, thank you.

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dellet
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Re: Expansion of bullets in a Subsonic cartridge.

Post by dellet » Fri Jan 20, 2023 10:49 pm

Information comes from all over including personal testing.

For example the bullet you mentioned can be found on Hornady’s website.
https://www.hornady.com/bullets/rifle/3 ... terlock-sp#!/

At the 2 minute mark of the featured video it gives the expansion at two different impact velocities.

Sometimes the information can be found with loaded ammo using the same bullet. It might show or give a max effective range. Say the max range or expansion size is listed at 500 yards from a 300 Winchester magnum. Reverse engineer it. Look at the Ballistic table for that loaded ammo. It will at least give muzzle velocity. From that you can calculate velocity at 500 yards. Not perfect but gets you in the ball park.

Look at enough bullets, you’ll see patterns. Then invest in some Ballistic gel and compare results. Less than $100 you can set up a decent kit. A mold and double boiler to melt it. Load up some reduced loads and then shoot at short distances, 10 yards is enough, and you will know exact impact velocity.

Most dedicated hunting bullets enough information is available on websites to figure it out . Most manufacturers will also freely give the info. Just takes time.

Finding it yourself will also Give you a bunch of other info that will be helpful. It’s worth it.
300 Blackout, not just for sub-sonics.

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Re: Expansion of bullets in a Subsonic cartridge.

Post by popper » Sat Jan 21, 2023 5:22 pm

The gold dot 300blk expands @ 1400 fps. Not much that will do better. Why expansion for javalina? Just poke 2 holes in them.

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bangbangping
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Re: Expansion of bullets in a Subsonic cartridge.

Post by bangbangping » Sun Jan 22, 2023 11:13 am

popper wrote:
Sat Jan 21, 2023 5:22 pm
The gold dot 300blk expands @ 1400 fps. Not much that will do better. Why expansion for javalina? Just poke 2 holes in them.
Two holes? And risk destroying all that delicious meat? :lol:

30 caliber expansion at subsonic velocities is tough. Even the Hornady 190 Sub-X, specifically made for subsonic use, is mediocre at best. Aside from casting your own, your best bet is probably to go with a copper bullet. Maker produces a variety of copper bullets designed for specific velocities.

Personally, I never accept a manufacturer's claims about expansion with a 300 BLK, sub or super. As dellet said, gel is cheap enough, and if you test it yourself you'll know for sure.

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