Yugo M70ab2 Grenade Launcher Valve

**Sinatra** · January 28th, 2010, 02:01 PM

My Century Yugo M70ab2 has a gas shut-off valve on the gas block for launching grenades. My understanding is that when the GL sight is in the upright position, this close off the valve to the gas tube so that (using a blank round) a grenade can be fired.

I have no intention of firing a grenade, but wondered if firing regular ammo while the GL sight is flipped up would cause a problem as far as feeding the next round. Anyone here have any experience with this?

**mojo** · January 28th, 2010, 03:43 PM

Originally Posted by Sinatra

My Century Yugo M70ab2 has a gas shut-off valve on the gas block for launching grenades. My understanding is that when the GL sight is in the upright position, this close off the valve to the gas tube so that (using a blank round) a grenade can be fired.

I have no intention of firing a grenade, but wondered if firing regular ammo while the GL sight is flipped up would cause a problem as far as feeding the next round. Anyone here have any experience with this?

You are correct. When you flip up the GL sight it completely shuts off the value and no gas goes into the tube. Why do this?

They needed the extra pressure to launch the grenades. And of course they had to be firing a blank at that time. I've heard stories of what happens when they didn't.

But to answer your question. Can you fire regular ammo with the GL sight up? Yep. The bolt won't cycle because no gas is pushing the piston back. So you have to manually chamber the next round. With the GL sight up, you basically are not running a semi-auto.

**Sinatra** · January 28th, 2010, 04:22 PM

"But to answer your question. Can you fire regular ammo with the GL sight up? Yep. The bolt won't cycle because no gas is pushing the piston back. So you have to manually chamber the next round. With the GL sight up, you basically are not running a semi-auto."

Ah, that's what I figured might happen. I wanted to make sure that it isn't a safety issue, but as you've stated, it's just a cycling issue.

Thank you.

**offshorebear** · January 28th, 2010, 04:37 PM

It turns it into a bolt action rifle. But you can't see the front sight with the grenade sights up anyway, so it's kind of useless.

**wa3ra** · January 28th, 2010, 05:07 PM

And like the man said, you do NOT want to chamber and fire a live round when it's up!

**brian** · January 28th, 2010, 09:04 PM

Originally Posted by wa3ra

And like the man said, you do NOT want to chamber and fire a live round when it's up!

and why is that again?

as long as there is no grenade on the end of it, there is no foul.

it would be cool to shoot a few through a cronoy, and then again with it up....just to see how much energy is lost to cycling the action.

**mojo** · January 29th, 2010, 09:06 AM

Originally Posted by wa3ra

And like the man said, you do NOT want to chamber and fire a live round when it's up!

You definitely can as long as there isn't anything hanging off the end of the barrel like a grenade or practice grenade.

Originally Posted by brian

and why is that again?

as long as there is no grenade on the end of it, there is no foul.

it would be cool to shoot a few through a cronoy, and then again with it up....just to see how much energy is lost to cycling the action.

+1