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acaixguard
11-26-11, 22:41
Tonight, after cleaning my M4, the front take down pin was stuck for a bit. I had to use a punch to drive it out (to the right), and to clese it took a bit of effort too. I put a few small drops of oil into the plunger (and spring) that holds the takedown pin either fully open or closed, and after working the pin left and right a few times, it seems back to normal now.
Does anyone know if something needs to be looked at? Was this due to me possibly degreasing everything too much and things got a bit gritty?

Thanks in advance!
polymorpheous
11-26-11, 22:44
Did you paint it?
Why did you degrease it?
acaixguard
11-26-11, 22:56
Didn't paint it or anything. I degrease the entire gun as part of regular cleaning. I use Slip 725 cleaner/degreaser, then relube everything the best I can.
polymorpheous
11-26-11, 23:01
http://m4carbine.net/showthread.php?t=35490


CLEANING SHOULD TAKE APPROXIMATELY 10 MINUTES OR LESS.
Tweak
11-26-11, 23:29
that's the pivot pin. Perhaps the tip of the detent, or edge of its hole in the pivot pin, is just sharp enough that oil can let it slip. It's worth popping out the pin and taking a look.
acaixguard
11-27-11, 09:34
Thanks all! Not sure what happened in that moment, but it all seems good now, particularly after I applied some oil to the pivot pin, and inside the groove of the takedown pin.
acaixguard
11-27-11, 09:35
http://m4carbine.net/showthread.php?t=35490

I still can't figure out how anyone can do a decent job of cleaning in 10 hours, or even under half an hour. Although, I am pretty OCD about my guns being clean. I like everything to be white glove clean whenever possible.
polymorpheous
11-27-11, 10:49
I still can't figure out how anyone can do a decent job of cleaning in 10 hours, or even under half an hour. Although, I am pretty OCD about my guns being clean. I like everything to be white glove clean whenever possible.

Over cleaning your carbine can damage it.
Iraqgunz
11-27-11, 17:29
The problem is that you are wasting unnecessary time and expense in cleaning. "White glove" cleaning is nonsense that some jack off in the military decided was a good thing when officers came to inspect the armory.

Please note the following BCG and charging handle. This came from my SBR which was used in the Magpul Dynamics Course in Tucson recently. On day two I wiped the BCG off with a rag and lubed with FrogLube.

When I got home I wiped it off and relubed and then shot about 200 rounds through it. It's still dirty and still running. In all it has had over 2100 rounds fired through it with nothing more than a wipe down and relube.

10352


I still can't figure out how anyone can do a decent job of cleaning in 10 hours, or even under half an hour. Although, I am pretty OCD about my guns being clean. I like everything to be white glove clean whenever possible.
nimdabew
11-28-11, 10:31
I still can't figure out how anyone can do a decent job of cleaning in 10 hours, or even under half an hour. Although, I am pretty OCD about my guns being clean. I like everything to be white glove clean whenever possible.

You're doing it wrong. I wipe all the internals down with an old t-shirt and then use a oil pistol to relube everything with 5w-40 from the autoparts store. Beyond that, it is kind of silly to do anything else except maybe a bore snake or maybe a tooth brush for hard to reach places.
MegademiC
11-28-11, 15:10
OP, what do you use for lube? a generous layer of a lube that stays(motor oil for example) allows most of the gunk to be wiped off. I just wipe, and hose out with gun scrubber and its clean except for a couple areas(bolt tail, ledge inside of carrier and barrel extension). I have no clue about your problem other than the detent may have been stuck.
acaixguard
11-28-11, 16:08
I use Weapon Shield. I think it's a great lube, and I noticed I spend less time cleaning since switching to that.
But yeah, things like corners, etc, will always have crud in it that's harder to get out. And that's where I obsess over.

But hey, I never said I clean my guns so it's white glove clean because it's necessary. It's OCD for sure. I just can't stand the site or feel of a gun that's dirty when I'm home handling them.
Outlaw621
12-01-11, 18:37
I had the same issue on a recent build. I was able to do what you did to get it working but after a little bit it would stick again. Once I completely removed the spring and detent and reinserted them everything has been perfect. It could be a piece of grit or a burr or to sharp of a point on the detent.
RDak
12-03-11, 05:39
I had the same issue on a recent build. I was able to do what you did to get it working but after a little bit it would stick again. Once I completely removed the spring and detent and reinserted them everything has been perfect. It could be a piece of grit or a burr or to sharp of a point on the detent.

That's almost exactly what happened to me a few years back when putting parts in a stripped lower.

I had messed up putting in the spring and detent. (Can't remember if I bent the spring or let some grit, etc., get into the hole and that bent the spring.)

Anyway, I took everything back out, cleaned the hole and used a different spring. Worked good thereafter.

This was my screwup initially.
donwalk
12-03-11, 21:24
military weapons are designed with lack of cleaning and maintenance in mind. virtually every SUCCESSFUL small arm designed for the military has succeeded because of that factor alone. when the cleaning issues were overcome, the M16 became a stalwart in the field of small arms.

a good example of a failure, though, was the Chechault (sp?) MG of WW1...way too easily jammed due to the magazine design with the mud and conditions of the WW1 trenches to operate.

when you have two dissimilar metals in a surface-to-surface contact situation, it's much better to maintain a clean/properly lubed surface to minimize any reaction; such as galling.

clean, de-burr and lightly lube... the pins should operate OK.
discreet
12-03-11, 22:25
Sometimes when I have come across pivot pins being a PITA, I put the rear pin half way or all the way back in, and it makes it a bunch easier to pull the front pin out. Leverage can play a lot in that front pin being stuck IMO. You should never have to beat the pin out IMO, as that just shows something is seized up bad. You can actually end up with a wider ID after time due to either compressing the metal, or shaving it out by doing so.


And for lube, for me it's Tetra Grease.

I just wipe and clean my BCG every few hundred rounds. Never had an issue doing so.
Artiz
12-05-11, 15:24
I'm wondering what the front and back pivot pins's expexted lifetime is. Anybody had a pin wear out?
lamarbrog
12-05-11, 16:41
Never had a pivot or take down pin wear out on any of my rifles, or rifles I have maintained. They're not exactly a high-use part... At least, not if you aren't way over-cleaning.

I'll agree that you're taking cleaning to an extreme that could potentially cause damage. Clean your bore (primarily the chamber), wipe down the internals, and apply generous lubrication. That's all you need to do.

If you feel like you could clean for 10 hours, something is wrong. When I get bored and do a "white glove" cleaning it still only takes about half an hour. A normal cleaning is a 10-15 minute job. I'd try a different lubricant... Ballistol is my personal favorite, I find it cleans and lubricates exceptionally well.