Front sight post fix?

ReluctantDecoy

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Got a cheap, most likely Chinese junk, set of BUIS from Amazon a while back. Hadn't really messed with them until recently. The flip up front sight is adjustable for elevation with the typical screw-in post/chevron and spring loaded pin to hold it at a setting. Problem is, the tolerances suck and the pin/spring pressure on the right side tilts the post to the left.

Any fixes for this or just "lesson learned" on buying cheap junk? I was thinking about pulling out the pin, finding zero, and JB Welding the pin in there. Won't have elevation anymore, but this is an under 50 yard PDW anyway. But I'm all ears if there are other easy fixes for this issue.
 
Got a cheap, most likely Chinese junk, set of BUIS from Amazon a while back. Hadn't really messed with them until recently. The flip up front sight is adjustable for elevation with the typical screw-in post/chevron and spring loaded pin to hold it at a setting. Problem is, the tolerances suck and the pin/spring pressure on the right side tilts the post to the left.

Any fixes for this or just "lesson learned" on buying cheap junk? I was thinking about pulling out the pin, finding zero, and JB Welding the pin in there. Won't have elevation anymore, but this is an under 50 yard PDW anyway. But I'm all ears if there are other easy fixes for this issue.
You could try loctite thread repair. It may be more of a PITA than its worth.

View: https://www.youtube.com/watch?v=XUU9FHB9XF4
 
Don't fix cheap junk. Just spend money on a good set of iron sights. Afterall, you're depending on those to shoot the gun accurately. Lots of good options out there. You always want the ability to adjust sights.
 
Don't fix cheap junk. Just spend money on a good set of iron sights. Afterall, you're depending on those to shoot the gun accurately. Lots of good options out there. You always want the ability to adjust sights.

Agreed. Can’t wrap my head around buying/attaching cheap and/or already broken parts to something your life may depend on. That’s like Master Level Skinflint. Good set of sights is literally like 80.00-180.00.
 
You could try loctite thread repair. It may be more of a PITA than its worth.

View: https://www.youtube.com/watch?v=XUU9FHB9XF4


Thanks. Is that stuff just an epoxy?

Don't fix cheap junk. Just spend money on a good set of iron sights. Afterall, you're depending on those to shoot the gun accurately. Lots of good options out there. You always want the ability to adjust sights.

These were cheap, but not bottom of the barrel. I think they were like $45. and had hundreds of great reviews. If I were going 100% skinflint, I would have gone the $19.99 route. But yes, in hindsight, I should have just dropped more cash for a proven solution. But other than this tilted post, the rest of the sight seems just fine, so I might try modding it first. I don't mind the fixed front sight. It would be just like my MP5 front sight at that point.

Agreed. Can’t wrap my head around buying/attaching cheap and/or already broken parts to something your life may depend on. That’s like Master Level Skinflint. Good set of sights is literally like 80.00-180.00.

I'll own the cheap part, but there's no way I could have known it was already broken. If anything, I thought the cheapness would be a longevity issue, not it being nearly unusable out of the box. And while I'll agree that buying a good name brand does matter here (in retrospect), I can't believe there are BUIS north of $150 on the market. There is seriously no reasonable explanation for that price gouging, even for name brand. These things aren't exactly marvels of engineering. Just a lump of metal with a couple springs and bearings. It's highway robbery that they are sold above even $100. I'm just having a hard time spending the same or even more on BUIS than my trigger group (ALG ACT).
 
Thanks. Is that stuff just an epoxy?



These were cheap, but not bottom of the barrel. I think they were like $45. and had hundreds of great reviews. If I were going 100% skinflint, I would have gone the $19.99 route. But yes, in hindsight, I should have just dropped more cash for a proven solution. But other than this tilted post, the rest of the sight seems just fine, so I might try modding it first. I don't mind the fixed front sight. It would be just like my MP5 front sight at that point.



I'll own the cheap part, but there's no way I could have known it was already broken. If anything, I thought the cheapness would be a longevity issue, not it being nearly unusable out of the box. And while I'll agree that buying a good name brand does matter here (in retrospect), I can't believe there are BUIS north of $150 on the market. There is seriously no reasonable explanation for that price gouging, even for name brand. These things aren't exactly marvels of engineering. Just a lump of metal with a couple springs and bearings. It's highway robbery that they are sold above even $100. I'm just having a hard time spending the same or even more on BUIS than my trigger group (ALG ACT).
Yes Epoxy , you could use almost any type of Epoxy. Remove front sight post, spring and detent . Clean it really well. Use some sort of release agent on the front sight post. Apply some Epoxy to the threads and reinstall with out spring and detent.
Your going to need to be careful not to over fill so the plunger/detent will fit back in and not bottom out on excessive Epoxy.
Juzt to be careful you might want to count the number of turns when removing it to put it back in the same. You will at least maintain your zero if it decides to stick.
 
Yes Epoxy , you could use almost any type of Epoxy. Remove front sight post, spring and detent . Clean it really well. Use some sort of release agent on the front sight post. Apply some Epoxy to the threads and reinstall with out spring and detent.
Your going to need to be careful not to over fill so the plunger/detent will fit back in and not bottom out on excessive Epoxy.
Juzt to be careful you might want to count the number of turns when removing it to put it back in the same. You will at least maintain your zero if it decides to stick.

Thanks. I was going to count turns, but also mark one of the four sides with paint marker so I could double check with orientation once zero'd. My only question on attempting this though was why the problem was happening in the first place. If it can tilt with the spring/pin pressure on one side, does that mean there's slack in the tolerance between the threaded portion of the sight post and the female socket? I suppose the epoxy should take up that slack, but that means ensuring vertical orientation while it cures.
 
Yes your going to have to thread it in as square as possible while the repair sludge does its thing. Heck you could probably use Teflon tape for a quick half fix.
First thing I would do is either decide to fix or return the sight. If you decide to fix it tear it down and see whats messed up.
You have to apply the repair goo in such a matter to not fill the detent hole or drill it out after?
Its a cheap sight, practice your field repair skills.
 
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