Hello, i have a special weapons SW5A in 9mm that will not feed when i slap the charging handle because the bolt does not travel far enpugh back to pick up a round. If i manually pull the charging handle to its rear most position i can then get it to feed correctly, and it fires semi-auto just fine thereafter. What is going on here? Im using an '84 HK mag, fyi. Thanks!
MP5 Feed issue, help!?
1 - 6 of 6 Posts
try replacing the recoil spring... just a thought?
Joined
·
8,570 Posts
Does the cocking tube slide with no resistance when the carrier is removed? And... does the bolt and carrier slide through the receiver with no resistance? If yes to either one of those, fix that first. Then check the recoil spring. One other possibility is that the hold-open notch is too far forward, either from wear, or from a cocking tube that wasn't quite snugged up to the receiver when it was welded.
Joined
·
6,213 Posts
It sounds like your problem is more related to Dave's second point here. If the notch isn't holding the bolt back far enough to pick up a round from the mag, that's your issue. Rather hard to believe though as it would have to be a HUGE fkup, since the edge of the bolt head sits just over .5" behind the rear of the round when in the locked back position. You can inspect it by looking through the ejection port wit a loaded mag inserted.
I think you've got another problem, or your gun very poorly built.
Joined
·
8,570 Posts
Yeah, if it's literally not back far enough to strip a round at all, that's a big problem. I don't know how the notch could even wear that far. Another possibility - the hole for the cocking handle in the cocking tube is drilled in the wrong spot. If it was too far away from the front, it wouldn't push the carrier backward far enough. Or the entire tube could simply be too short. Or heck, could an mp5k carrier cause this problem? Did they use US made cocking tubes? If that's the case it could be as simple as changing the tube, or bolt carrier. If it works totally fine after the first shot is fired, I bet it's an issue with the cocking tube or bolt carrier. Get some pics of the carrier and maybe the cocking tube and we may be able to tell.
Sent from my iPhone using Tapatalk Pro
Sent from my iPhone using Tapatalk Pro
Some of the SW5 guns had out of spec bolt carriers and cocking tubes.
I had one where the bolt carrier upper was a bit short- but still worked fine (.5" fudge factor to play with). In order to fit an in-spec bolt carrier, the cocking tube had to be shaved down.
If a bad enough combo of parts got in there, I could see your problem happening.
A new bolt carrier or cocking tube may fix your issue, but if they set the stop piece for the cocking tube too far back, you'll have false bolt gap issues. Ideal fix if that happens is to un-weld the stop ring and weld it back in the RIGHT place.
Best to let an expert check it out, or someone local who knows what they're doing.
-Dave
I had one where the bolt carrier upper was a bit short- but still worked fine (.5" fudge factor to play with). In order to fit an in-spec bolt carrier, the cocking tube had to be shaved down.
If a bad enough combo of parts got in there, I could see your problem happening.
A new bolt carrier or cocking tube may fix your issue, but if they set the stop piece for the cocking tube too far back, you'll have false bolt gap issues. Ideal fix if that happens is to un-weld the stop ring and weld it back in the RIGHT place.
Best to let an expert check it out, or someone local who knows what they're doing.
-Dave
1 - 6 of 6 Posts
