Is There Subsonic 300 Blackout Ammo With a Lead-Free Primer?

By Roland Polzin, co-founder and CEO of EcoBullet. You'll find our current 300 BLK stock on the product page.

EcoBullet Shadow is a subsonic 300 Blackout load with a lead-free primer: a 220-grain total metal jacket (TMJ) bullet going about 1,010 feet per second, built for suppressed rifles, in boxes of 50 for $54.99 ($1.10 per round). The primer contains no lead styphnate, and the bullet's lead core is fully enclosed (including the base). With a suppressor, this matters especially because your rifle blows part of this toxic cloud back toward your face.

Why the primer matters more with a suppressor

A suppressor functions by capturing and slowing down the gases that escape the barrel behind the bullet. Everything in that cloud that isn't gas (including what's left of the primer) either stays in the baffles or comes out somewhere. On an AR, this gas also travels through the gas reloading system, which is why suppressed ARs are known for blowback at the charging handle and the ejection port. Since a conventional primer contains a lot of lead styphnate, that blowback carries lead right into your face and, when you breathe, into your lungs.

A lead-free primer changes what's in that gas at the source: it reduces a major source of lead in the fouling where you handle the rifle and in the air a few inches from your face. The total metal jacket does the same job on the bullet: since all lead is covered (jacketed), no lead at the base can vaporize. Range operators who want to understand exposure limits and sources of range lead can read our post on why ranges are switching to lead-free training ammunition.

I see the difference in my own 9mm: after about 500 rounds with our lead-free primer, my P8 shows almost no fouling. A suppressed rifle traps far more of what the primer leaves behind than a pistol does, which is exactly why we built Shadow for the can.

What "subsonic" means for 300 Blackout

The speed of sound in air is roughly 1,100 feet per second at the temperatures most people shoot in, and it drops as the air gets colder. A bullet below that speed doesn't produce the crack of a sonic boom, which is why our 300 Blackout runs just under that speed at about 1,010 feet per second: a heavy bullet (220 grains) accelerated just enough to cycle a rifle while staying quiet.

The heavy bullet is also why twist rate matters. A long 220-grain bullet needs to twist fast to stabilize, and Shadow is optimized for 1:7 to 1:8 twist barrels, which most 300 Blackout rifles and pistols use. With a slower twist, a subsonic 220-grain bullet from any maker may not stabilize, and you'll see keyholes on the target.

What Shadow is

Shadow is our most specialized round, loaded in new production brass (instead of recycled) to SAAMI specifications. It comes in boxes of 50, so one box is a proper range session instead of a 20-round "sample".

Will it cycle and stabilize?

Subsonic 300 Blackout from any manufacturer depends on the gun:

1. A suppressed rifle sees more gas pressure in its system and usually cycles subsonic ammunition very well.
2. An unsuppressed rifle with a standard carbine gas system may not cycle as well and may need an adjustable gas block.
3. Our lead-free primers have been proven for decades and support smooth cycling and stable shots.

We're still having Shadow independently tested to post those results here. Outside reviewers have tested our 9 mm, with velocity and consistency data (see our post on whether lead-free ammo is as reliable as standard ammo), and Shadow is made with the same care and workmanship. We encourage you to run one box through your own rifle (suppressed and unsuppressed, if you run both) before you buy more.

If your rifle short-strokes

Short-stroking means the bolt doesn't lock back on an empty magazine, or the next round doesn't feed. The common fixes:

• Attach the suppressor: the added back-pressure gives the action more gas.
• Open an adjustable gas block a step at a time, or use one tuned for subsonics.
• A pistol-length gas system runs subsonics more easily than a carbine-length one.
• Try a lighter buffer or buffer spring.

Bolt-action and single-shot rifles don't depend on gas at all, so cycling isn't a question there; twist rate still is.

What Shadow isn't

Shadow is not a hunting round. A total metal jacket bullet at subsonic speed doesn't expand. It's also not completely lead-free: the bullet has a lead core, so it leaves lead wherever the bullet lands and doesn't count as nonlead ammunition under hunting rules (especially in California). In a nutshell, it's a quiet practice cartridge for suppressed rifles that keeps lead away from you.

Frequently asked questions

What is the advantage of subsonic 300 Blackout with a suppressor?

A subsonic bullet doesn't produce a sonic crack, so it's quiet beyond the explosion noise. With a suppressor, subsonic 300 Blackout is one of the quietest centerfire rifle combinations available, which is what we designed the cartridge for.

Why does the primer matter more with a suppressor?

A suppressor traps the gas and residue that follow the bullet, and on a gas-operated rifle, much of that comes back through the action toward the shooter. With a conventional primer, that residue includes toxic lead. A lead-free primer reduces that source of lead in the fouling and the blowback.

Will EcoBullet Shadow cycle an unsuppressed AR?

It depends on the rifle, as with every subsonic 300 Blackout load. Suppressed rifles usually cycle subsonic ammunition reliably; however, unsuppressed rifles with a standard gas system may not. You may want to use an adjustable gas block and test a box of Shadow with your own setup.

What twist rate does a 220 grain subsonic bullet need?

A fast one. EcoBullet Shadow is optimized for 1:7 to 1:8 twist barrels, which covers most 300 Blackout rifles and pistols. Slower twists may not stabilize a 220-grain bullet at subsonic speed, so consider this before buying in bulk.

Can I shoot Shadow in a bolt-action rifle?

Yes. Bolt-action and single-shot rifles don't depend on gas to cycle, so subsonic function isn't an issue. The twist rate still matters: Shadow is made for 1:7 to 1:8 barrels.

Is the bullet lead-free?

The primer is lead-free, and the bullet is a total metal jacket with a fully enclosed lead core (including the base). That keeps lead out of the gas at ignition and off the bullet base; however, it doesn't technically make the projectile "non-lead".

Where can I buy lead-free primer 300 Blackout?

Directly from ecobullet.us, shipped by ground in boxes of 50. Orders over $199 (after discounts) ship free within the contiguous 48 states. You must be 21 or older to order, and some states require delivery to a licensed dealer or a permit on file; each state has its own rules, which you can find in our state-by-state shipping guide.

Questions about the load, twist rates, or shipping to your state? Write to info@ecobullet.us, use our website chat, or call +1 423 445 0808.