Had one of these old tanker helmets I had converted before getting an actual  commercial built helmet. I thought I would take it outside and hit it from 25' with 115gr 9mm FMJ. Seems to be they may not be what they are rated for? Several of the holes are penetrating through and through

You gave it multiple hits of 115 gr 9mm, which is on the cusp for many of those old CVC shells. They were made for shrapnel at a relatively low speed except for some more improved versions.

While some were IIIA, I thought a lot of CVC helmets were IIA.

The military doesn’t typically require a helmet to stop 9mm. That’s mostly a police thing. And point in fact, NIJs IIIa standard isn’t for helmets. You can but a helmet guaranteed by the manufacturer to stop those threats but it can’t get the NIJ certification.

This, and the US Military uses it's own set of test standards to rate helmets.  Most CVC shells are only ballistically rated for frag protection.  There is a recent revision that carries a 9mm protection rating, but those probably aren't common in surplus yet.

9mm rating for a helmet is kind of silly anyway.

I know 2 guys whos helmets stopped bullets. both of them got knocked stupid, one cannot move his head more than 45 degrees in either direction now.

so what?

If you are in a gunfight and take a shot to the dome, you're going down. period.
the next shot you take is going into something that bleeds.

That's not the army ECH  experience in Afghanistan or Iraq. If the small arms fire did not completely penetrate the helmet, 100% of those soldiers returned to duty.

https://www.pmi.org/-/media/pmi/documents/public/pdf/learning/pmj/early-edition/feb-mar-2018/j20180296.pdf

Yes, someone also posted a story about the Army sergeant that took a 7.62x54R machine gun round to the ECH helmet and survived, recovered

My bil took a 762x54 to the head. His squad took out the sniper and kept him safe. He's still alive.

His helmet deflected the bullet enough he just got knocked out and a nice scar.

Yes. Guarantee he got knocked senseless, and then his squad killed the guy. One of the guys I mentioned had his helmet stop and Ak bullet, the other one stopped a shot from an SVD. SVD bullet blew his NODs mount apart, and he went down out cold for a solid 15-20 seconds. When he got up, he was throwing up and stumbling around till the medic grabbed his ass and pulled him into cover.

Yah man RTD doesn’t mean they just go “ow,” take a knee, and sally forth like Master Chief.

Remember: a helmet's primary purpose is to protect your head from bumps and bashes. Ballistic effects are secondary, and usually quite limited in nature. The only helmets that focus heavily on ballistic ones are those shitty Chinese helmets like Hard Head Veterans and similar Chinesium-made shells that you see for <$100. Their bump protection is questionable. It's not hard to get a thin layer of hard ballistic protection by just layering aramids and resin-curing them. Making them last and perform the same from batch to batch though...another story.

Most of the bump protection comes from the foam liners and the padding system used, the shell just provides protection from penetration.

If you're just wanting bump protection, you can find NIB bump helmets for not much more than a surplus helmet'll cost. Upside: you know how the helmet was manufactured, stored, cared for, and who was a previous user (no one). If you want a ballistic, spend a bit more and get a Gentex or Galvion.

Interesting. I've watched bunches of videos testing old surplus ACH and PASGT helmets and they always stop 9mm easily, never seen a CVC tested though. I would have assumed they could stop 9mm and were made the same as other Kevlar helmets, now I know they aren't. Seems like a helmet to avoid if you're wanting one for any ballistic protection.

The military has three main concerns with ballistic helmets:

1. Shrapnel from overhead airbursting explosive ordnance.

2. Glancing impacts from rifle rounds while peaking your head around cover.

3. Bashes and other impacts from hitting your head on things or having things fall on your head, typical of hardhats.

Protection from headshots by handgun rounds, as another poster said, is more applicable to law enforcement than the military. I think the military just asks for Level IIIA as a pretense for "Hey, precision guided airbursting ordnance from drones is becoming more prevalent, we need our helmets to be better at stopping shrapnel, more shrapnel, bigger shrapnel, faster shrapnel. Let's simplify that for manufacturers by asking for IIIA."

Just buy a second, larger helmet and put it over yours.

Yeah he was out for a little bit. I actually think he got sent home after that but don't remember.

They took the guy out too. That how they knew it was a x54. I think it was a svd too iirc

The original CVC shells weren't even made of Kevlar. I still have a couple from when I was in the Army. I made a high cut bump helmet out of one of them. And everyone is correct that helmets are meant more for protection from shrapnel than from bullets, especially true for CVC helmets. Guys actually wearing CVC helmets in combat spend most of their time inside their armored vehicles. I'm nt sure when the Army started issuing kevlar CVC helmets but it had to be after I retired in 1996.