Special Weapons SW-5 failure to eject...

[timuchin]

Anyone know anything about these things? It's an MP-5 clone. A buddy of mine bought one, and it's a pain in the neck. It extracts fine, but the bolt carrier doesn't travel far enough rearward to cam up the ejector and eject the spent case. The empty case just goes right back into the chamber. The bolt does travel far enough back to strip the next round off of the magazine though, jamming it on the feedramp under the bolt carrier. I think that part of the problem is that the chamber isn't fluted. What are his options to fix it? I keep telling him to get the barrel replaced and be done with it, as he doesn't want to buy special ammo. (I think that some of the Hirtenberger stuff would work nicely.) Any ideas?

 

[John@JCDLESales]

Here Are A Few Things To Check

First off you say it extracts fine just doesn't eject right. Not a barrel problem so cross that off your list. The SW 5's are not highly regarded for their Mag Lock Up. Sounds like a mag sitting to high and the bolt carrier dragging across the lips with US Factory Ammo. Most of the Hirtenberg 9mm was MG ammo and HOT so that is why it functions with it so well. Most US 9mm is produced for pistols and not nearly as HOT.

Try some other mags POF's work every bit as good as factory HK mags by the way. Or you could try slopping on alot of a good friction modifier on the bottom of the Bolt Carrier with some downward tension on the existing mag during firing and see if that works. If it does then you know it is a Mag Lock Up Problem and go from there.

 

[timuchin]

Definitely not the magazine.

Does the same thing with the mag removed. Maybe the roller recesses aren't at the correct angle, and the unlocking delay is too long. It's driving me nuts. Everything else seems to work fine.

 

[John@JCDLESales]

The Bolt Carrier Is Dragging On Something

As you said it works fine running on Hintenberg SMG Ammo. Check the recoil spring rod for burrs. Also check the spring itself and make sure it is an MP5 Spring and not broken or kinked. I really don't see the Rollers being the source of the problem as it is a Semi and that problem would be exhibited in FA Mode. But to check this you could remove the rollers and check function with just 2 Rds. in the weapon. Let me know what transpires if you will.

John

 

[timuchin]

I haven't tried the hirtenberger stuff yet...

The bolt carrier dragging occured to me too, but there aren't any wear marks on the carrier. I hadn't thought of removing the rollers. I might try that on my next trip to the range.