Howdy folks.

I picked up an STG58 on an Imbel receiver from a very trusted dealer. I test fired it at their range and it was flawless.

Flash forward to this afternoon (my first day out with it since buying it) and it was a disaster!

After firing, the bolt locks up. The carrier is back about half an inch but the bolt/empty case haven't moved at all. I took the rifle apart and whacked the charging handle backwards (using a table) and it flew back and out popped the casing.


I did this about 5 times. Same thing every time.

I can cycle live rounds just peachy. Went through about 10... smooth as silk. When I chambered a spent casing, I got the super-duper stuck bolt problem again.

The bore is bright and shiny. I pulled a boresnake through her a few times and triple-checked for dirt/obstructions. Nothing...

With the lower receiver removed and the upper upside down, the bolt/carrier slides very smoothly in and out of battery. I just had to admire the design... while also cursing the thing for what it was doing to me.

Does anyone have any ideas? I was using South African surplus, which has ALWAYS treated me right. Hell, if even worked in my (now sold) CETME.

I'm just perplexed at this point.

-  BG

Sounds like you need to get more gas pressure. I'd go through the steps to make sure your regulator is set properly for your ammo.  If you rec'd a manual with the rifle it should be right in there, otherwise swing by the FALfiles and check out their FAQ's

HTH

Blitz

Are you using different ammo than the dealer? And/or the gas setting was changed since test firing.

I... uh... well...


It appears that the higher the gas #, the less amount of gas comes out... and... uhh... well... I kinda shut the gas off to the whole system.  


I don't see how that explains the bolt being "stuck" but it sure explains ZERO movement after firing.


"People who suggest you read manuals first:"   One Point
BUCC_Guy:                                                   Zero points.



- BG

Quoted: I... uh... well... It appears that the higher the gas #, the less amount of gas comes out... and... uhh... well... I kinda shut the gas off to the whole system.   I don't see how that explains the bolt being "stuck" but it sure explains ZERO movement after firing. "People who suggest you read manuals first:"   One Point BUCC_Guy:                                                   Zero points. - BG

Sure it explains the bolt being stuck.  The case swells to fit the chamber upon firing, "jamming" the case in the chamber.  The proper gas setting imparts enough energy for the bolt carrier to "yank" the bolt and thus the case out of the chamber and eject the case.  As you have manually removed the case you understand the force needed to remove a fired case from the chamber, the same amount of force is exerted on the the bolt carrier by the piston via the expanding gas.  Not enough gas, the bolt can't overcome the force fit case.

I'll be making an emergency trip to the range tomorrow to check up on all this... its starting to actually make sense.  


- BG

Gas adjustment on FAL

Lower number is MORE gas to the piston, STIFFER recoil, HARDER ejection.

Higher number is LESS gas to the piston, GENTLER recoil, SOFTER ejection.

Guys do it from both directions, from a lower number until they reach a higher number that no longer allows bolt hold-open, then one or two clicks lower for reliability... or from the high end down until the bolt hold-open finally works, then 1-2 clicks etc.

Metric gas adjustment rings, if numbered, are 1 to 7. Inch gas adjustment rings are 1 to 11.

A spent cartridge will not cycle smoothly from any action.  It would have to be resized to it's original dimensions prior to firing for that to work.

As another poster mentioned.  Cases expand to the chamber walls durring firing, and thus require a lot of force to yank them lose.  

Quoted: A spent cartridge will not cycle smoothly from any action.  It would have to be resized to it's original dimensions prior to firing for that to work. As another poster mentioned.  Cases expand to the chamber walls durring firing, and thus require a lot of force to yank them lose.

Cases do expand but they contract when chamber pressure is reduced. Cases should not be sticking in the chamber regardless of what gas setting the rifle is on. Pulling out fired cases should be a smooth operation. Are bolt action rifles hard to cycle after firing? Is an AR with no gas tube hard to cycle by hand after firing? No.

Since the original poster did not say what kind of ammunition he is having trouble with I can only suggest head spacing the gun. If the gun is head spaced tight then higher pressure rounds could be the culprit of the problem. If that is the case then a different locking shoulder is all that is needed to fix the problem.

Make sure you are not trying to launch a grenade and are using quality ammunition.

Quoted: Make sure you are not trying to launch a grenade and are using quality ammunition.

The gas shut off would not cause fired cases to get stuck in the chamber.

Quoted: Quoted: Make sure you are not trying to launch a grenade and are using quality ammunition. The gas shut off would not cause fired cases to get stuck in the chamber.

You are partially correct.  Bolt guns have much tighter chambers than autos thus the case can not expand as much though they still do expand.  The extraction on a hand-operated semi-auto is much easier precisely because there was ZERO gas acting in the system.  With insufficient gas pressure to allow the system to cycle correctly, the bolt carrier still moves but not enough to eject the case and then jams the fire formed case back into the chamber with considerable force.  The reinsertion of the case is where the sticky case removal comes from.

.

Quoted: Quoted: A spent cartridge will not cycle smoothly from any action.  It would have to be resized to it's original dimensions prior to firing for that to work. As another poster mentioned.  Cases expand to the chamber walls durring firing, and thus require a lot of force to yank them lose.   Cases do expand but they contract when chamber pressure is reduced. Cases should not be sticking in the chamber regardless of what gas setting the rifle is on. Pulling out fired cases should be a smooth operation. Are bolt action rifles hard to cycle after firing? Is an AR with no gas tube hard to cycle by hand after firing? No. Since the original poster did not say what kind of ammunition he is having trouble with I can only suggest head spacing the gun. If the gun is head spaced tight then higher pressure rounds could be the culprit of the problem. If that is the case then a different locking shoulder is all that is needed to fix the problem.

The bullet sealer used by the South Africans sometimes oozes between the case mouth and chamber wall and "glues" the case into the chamber upon firing. With enough gas, it unsticks.  This does not seem to happen with Aussie and Port. You may want to try different ammo.

I did not get out to the range as planned since the first post.

However, it occurred to me that after firing the hammer was indeed reset.  I think the bolt was slamming that empty case back in, resulting in my "stuck" bolt.


- BG

Quoted: Quoted: A spent cartridge will not cycle smoothly from any action.  It would have to be resized to it's original dimensions prior to firing for that to work. As another poster mentioned.  Cases expand to the chamber walls durring firing, and thus require a lot of force to yank them lose.   Cases do expand but they contract when chamber pressure is reduced. Cases should not be sticking in the chamber regardless of what gas setting the rifle is on. Pulling out fired cases should be a smooth operation. Are bolt action rifles hard to cycle after firing? Is an AR with no gas tube hard to cycle by hand after firing? No. Since the original poster did not say what kind of ammunition he is having trouble with I can only suggest head spacing the gun. If the gun is head spaced tight then higher pressure rounds could be the culprit of the problem. If that is the case then a different locking shoulder is all that is needed to fix the problem.

Bolt action rifles are cycled a large number of milliseconds after the round has fired and the case has had longer to cool and contract.  The same with a gas obstructed AR.  Pulling an expanded cartridge out of the action small fractions of a second after it has fired is not the same deal.  If you have a chamber with some tooling marks still inside it can be even a little rougher.  Rough enough to leave marks on the case.

On the other hand, I do have to note that once they have cooled they probably won't allow the bolt to close and may stick if you beat it home, but they should slide in and out with little effort.  I wasn't thinking right on that comment.

Quoted: Quoted: Quoted: Make sure you are not trying to launch a grenade and are using quality ammunition. The gas shut off would not cause fired cases to get stuck in the chamber. You are partially correct.  Bolt guns have much tighter chambers than autos thus the case can not expand as much though they still do expand.  The extraction on a hand-operated semi-auto is much easier precisely because there was ZERO gas acting in the system.  With insufficient gas pressure to allow the system to cycle correctly, the bolt carrier still moves but not enough to eject the case and then jams the fire formed case back into the chamber with considerable force.  The reinsertion of the case is where the sticky case removal comes from.

Another good point.  I've had that happen too.  Fired, action seemed to cycle, pull trigger, click, pogo stick removal needed.

You might want to check you gas pistion to make sure it is in the right way, Don't ask me how I know, had the same problem with a L1A1.  

Also check to be sure the gas plug is not set to the grenade position. This would block gas from unlocking the bolt. It's easy to do when cleaning your gas piston and you shouldn't even need to ask how I know.

heathen

Also check to be sure the gas plug is not set to the grenade position. This would block gas from unlocking the bolt. It's easy to do when cleaning your gas piston

+ 1


I uh... um..... I had a buddy... who had an FAL... and he did that...

I'ed never do that. Ever.


-Teflon

Quoted: heathen Also check to be sure the gas plug is not set to the grenade position. This would block gas from unlocking the bolt. It's easy to do when cleaning your gas piston + 1 I uh... um..... I had a buddy... who had an FAL... and he did that... I'ed never do that. Ever. -Teflon

two things ---if your bolt is going back far enough to reset the hammer but not extract the case far enough to hit the ejector (short cycling) and then slamming it back in --more gas pressure to the piston should cure it.
Also if the rifle is fired for long peiods without cleaning the gas port can be closed down to help overcome fouling and increased resistance within the system. After cleaning you should be able to open the gas port up back to your baseline setting and mitigate some of the recoil. CAVIM  ammo was especially dirty to the gas system and was notorious for guys having to close down the gas regulator to get the rifle to keep running after a few mags.

and two if the gas system is set to "G" or grenade -notch or "A" on one side of gas plug pointing down toward barrel- the rifle will not cycle at all the FAL and its rifle grenades were designed for manual operation and full gas pressure imparted to the grenade --it uses a special grenade blank --not a regular blank- to fire rifle grenades the grenades are not the bullet trap type. and the FAL is designed to be placed butt to the ground forearm held up like a mortar or rifle butt UNDER the armpit for firing grenades --fring a rifle grenade witha grenade blank and the rifle mounted to the shoulder would most likely result in a severly bruised if not broken shoulder(bad day). the gas cuttoff also serves to help prevent a live cartridge from being loaded automaticlly after a grenade is fired and then inadvertently mounting a fresh grenade and detonating it with a live round upon firing(really bad day).