How Does It Work: Lever Delayed Blowback

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Genre: Education

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Forgotten Weapons

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Shared July 11, 2019

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Lever-delayed blowback is a relatively uncommon action system, although it is applicable to a wide variety fo firearms and has been successfully used in submachine guns, rifles, and light machine guns. It uses a principle of mechanical disadvantage on a fulcrum lever to force a mass to accelerate rearward while the bolt remains closed. This allows the effective weight of the moving parts to be amplified, resulting in a lighter firearm.

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Admit it Ian, you just wanted to show us your FAMAS.

1 week ago | [YT] | 632


"...only a relatively small number have ever made it into MAS production..."
I see what you did there ;-)

1 week ago | [YT] | 76

Jason Armstrong

Can’t wait for the video on roller delayed blowback

1 week ago | [YT] | 167


Ian, your Famas is filthy! Have you been shooting it a lot? ;)

1 week ago | [YT] | 94

Colburn F

I was hoping to see TKB-517 that Ian found in Narnia... I'll get over it, the FAMAS is pretty cool.

1 week ago | [YT] | 47


in french we call this system "inertia amplification" (in AA52 and FAMAS)

1 week ago (edited) | [YT] | 23

Peter Kröger

Only a few have made it into MAS-production...;-)

1 week ago | [YT] | 11

Shaggy Shaggio

InRange shoots a match and features another bullpup in several videos

Ian: "I must find a reason to make a video with the Famas..."

Great video! Really loving the "How Does It Work" series. Its nice to get a good clear and simple explanation about how different firearms technologies work.

Cheers! <3

1 week ago | [YT] | 25

Nathan Boulton

once again, another highly informative video. I really can't say it enough, but thank you.

1 week ago | [YT] | 32

Davey J

When I think I know something about guns and then watch an episode of forgotten weapons.

I know nothing

1 week ago | [YT] | 17

Si_Vis_Pacem Para_Bellum

" How can I show my FAMAS without showing my FAMAS? " 🤔
making video about lever delayed action

1 week ago | [YT] | 7

Caleb Dehart

Ian.....please do a Knights Armory Masterkey video! Was mad I couldn't get my hands on one when I was fighting in Afghanistan.

1 week ago | [YT] | 8

eric money

I swear the famas bipods look like a couple of ratchets stuck on the side of the gun.

1 week ago | [YT] | 14

Peter Yi

I've always wanted to know this one, it always confused me hard.

1 week ago | [YT] | 14

Kyle Glenn

I didn't know that I had questions about lever delayed blowback systems!

5 days ago | [YT] | 1


Nice video, maybe next time mention or at least show on screen for one second the names of the guns you used as examples. The FAMAS might be obvious but the SMG isn't as much...

3 days ago | [YT] | 1

Vitor Roma

We need a modern PCC using this.

1 week ago | [YT] | 8


Love these videos focused on the mechanical aspects of firearm design. Very basic, but essential information for firearm enthusiasts! Thanks Ian!

1 week ago | [YT] | 1


I didn’t know I had questions about lever delayed blowback. Now, I have so many.

1 week ago | [YT] | 1

Luis Santiago

Sexy Famas. Appreciate the educational videos. Makes me want to be up early just so I can watch em as soon as you post.

1 week ago | [YT] | 1