Bad selector switch

[arodgers]

I pieced together my lower 3 or 4 years ago before I knew anything at all about the AR platform and I used a DPMS lower parts kit. The lower functions well (I've put almost 1,000 rounds through it over the last month with zero problems) but the selector switch is... mushy, for lack of a better word. It seems to get caught halfway between safe and fire sometimes, and the detent is etching a clear groove into the selector. I'd like to replace at least the selector assembly, so I have a few questions.

I see LWRC sells their parts individually and I'm looking at $10 for a selector, detent, and spring. Should I go with another brand or does that seem like a good option? Is there anything I'm overlooking that needs to be replaced?

I would just replace the whole LPK, but I don't need the grip or trigger group and the takedown pins/detents are all working fine.

Thanks in advance for any advice.

[xbmxracerx]

What condition is the original spring in? Have you upgraded to an aftermarket grip and maybe the spring was damaged in the process?

[Quiet-Matt]

Those parts should be all you need to replace. I have found selectors to be hit or miss no matter who you get them from. Buy a complete LPK, chances are you'll need something else outta the kit on down the line. Grant gives you good stuff with options... http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=GRT-LPK&reference=/cgi-bin/commerce.cgi%3Fsearch%3Daction%26keywords%3Dkits%26searchstart%3D0%26template%3DPDGCommTemplates/FullNav/SearchResult.html

[arodgers]

What condition is the original spring in? Have you upgraded to an aftermarket grip and maybe the spring was damaged in the process?

Spring looks good. I've taken it out twice to inspect it and see if I put it in wrong, and can't fix the issue. I do have a Magpul grip, but that was installed at the same time as the LPK.


Those parts should be all you need to replace. I have found selectors to be hit or miss no matter who you get them from. Buy a complete LPK, chances are you'll need something else outta the kit on down the line. Grant gives you good stuff with options... http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=GRT-LPK&reference=/cgi-bin/commerce.cgi%3Fsearch%3Daction%26keywords%3Dkits%26searchstart%3D0%26template%3DPDGCommTemplates/FullNav/SearchResult.html

That seems like it's just what I'm looking for. Everything but the fire control group and grip. Thanks for the link.

[ALCOAR]

At the very most you would just need a new spring(longer to provide more tension) and new detent.

Real quick if you have a moment, pop out your existing spring and gingerly stretch out that spring as far as you can....note that it should be kinda difficult to really stretch it but it can be done and the amt. needed is not anything extreme. Then just re install it and see how that works first.

[arodgers]

At the very most you would just need a new spring(longer to provide more tension) and new detent.

Real quick if you have a moment, pop out your existing spring and gingerly stretch out that spring as far as you can....note that it should be kinda difficult to really stretch it but it can be done and the amt. needed is not anything extreme. Then just re install it and see how that works first.

I was able to stretch the spring a bit. It has a more positive feel, but it is still really gritty feeling and will stick in between positions. I took a picture of the detent and selector while I had them out. Does the gouging in the selector from the detent look normal?

http://img210.imageshack.us/img210/852/dsc9711.jpg

http://img809.imageshack.us/img809/7162/dsc9713t.jpg

[ALCOAR]

If you got a bit more improvement in one form or another with respect to the actuation by stretching your detent spring than I would again stretch that current spring as much as I could until either I was happy with the selector's actuation or could not smidge anymore stretch outta the spring.

While your grooves clearly are a bit worn, my guess is that its not enough to cause your problem and neither is that detent pic'd...which leads us to the detent spring as the most likely culprit.

[Duffy]

I thought you were referring to our selector :p

We've done lots of research on this. The mushy feel can happen to any selector, this can usually be attributed to:

Receiver's detent/detent housing (hole for the detent and spring), if it's drilled a little off, the detent isn't sitting squarely in the selector's detent holes, and isn't riding on the detent groove with good contact.

Pistol grip and detent spring. These two have to do with the spring tension, grips that seat the spring deeper have less tension exerted on the detent, and an old or shorter spring can have less tension.

Detent. The detent you have seems pretty beat up.

On cast selectors, the contact between the detent and the cast selector's detent groove is not so good, see pic below, left is Battle Arms Dev. semi auto selector, right is a typical cast selector:

http://i75.photobucket.com/albums/i314/Duffypoo/detentgroovecomps.jpg

Selector itself. Cast selector's detent holes are sloppy and wider than need be. A worn detent isn't seating in the holes as well as it used to, resulting in soft and less than positive clicks when the detent is engaged.

Your detent groove seems pretty worn. The groove is now probably lower than it used be. Combined with a worn detent, it would have the effect you have now.

[arodgers]

It's worn, but it's felt like this since new and really isn't that old. My father has an LMT and a Colt and both feel like a "click" back and forth. For mine to be as worn as it is with as little time as I've had it, is it possible it's just an inferior metal?

I went ahead and ordered the stripped LPK from G&R. Hopefully that will solve my problem.