1911Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
1,345 Posts
It pains me to post this. On the bright side it was an easy fix, and it taught me to reel myself in especially when it's late and I should have slept on it.

Yesterday I cleaned a bunch of rifles and pistols I took to the range this past Saturday. I also have four stripped AR15 lowers in the safe. I had ordered a couple of build kits last week, and the big brown truck dropped them off yesterday evening. Since the safe is open I start building them around 11pm last night while watching The Force Awakens with my son. I'm farting around, beating in time, and finish them around 12:30. Get my son to bed, and go back to take them downstairs to put in the safe and I notice the rear takedown pin won't move on one of them. Strike one is that I didn't function check that one after I installed it before staking the castle nut.

What I first noticed was that the takedown pin was not flush to the lower in the "in" position, and I couldn't move it by hand in. I've had a few takedown pins in the past that were a little sticky and tighter that needed a little "persuasion" to move. I've already staked the castle nut so I don't want to take it off, bugger it up, and make it look like crap. I'm tired and just really wanting to go to bed as yesterday was just a hell of a day. Oh yeah, I really should have taken that castle nut loose!

Since my punches and hammer are still lying there I figure I'll just tap it and it will move. Tap it once, nah doesn't budge. Tap it twice, nope still won't budge, tap it a little harder for a third time, and now I'm pissed. I know I've assembled it properly, and figure it's a bur or something in the detent hole not letting it move so I hit that sum bitch pretty damn hard and this is the result. This is where my "learn from my mistake" comes in. If you have a REAL tight rear takedown pin, don't lay into it's ass with a hammer and punch. Just bite the bullet and remove the castle nut off the receiver extension and take out the detent spring and detent because if you hammer the hell out of it then it'll look like this...



I had never seen this type of damage before, and thankfully I'm not the first one to do it. The good news is there is a simple, cheap, easy fix, and I did not ruin the lower receiver as I thought I had. I used my Google Foo, and came across a couple of threads which one gave me the fix idea. The second link involves using a drill press, and that's something I don't own. I'll post it in case someone has the tools to fix something like this that way though.





So, armed with this knowledge I sleep on it. I get up this morning and go to my local fastener store looking for 3/32 drill rod. They don't stock it, but tell me Lowe's carrys it. I go to the hardware section at Lowe's, and find this. It's not called drill rod, but I can't bend it. It also doesn't list the size, but I can tell it's close by looking at the bolt sizing tool. The largest size is a perfect fit. So, I spend $2.98 and tax and take it home with me.



Basically the long and short of it is that I just made a longer takedown detent since there's still a large portion of the hole remaining to keep the detent in place. The detent I made doesn't flex, is solid and there's not sponginess. I had to use my bolt cutters to cut it that's how hard it is. I could not cut or dent it with regular cutter pliers. Hand sanded the tip and the back of it to make it straight, slipped it in the lower and viola it works like a champ. I was seriously ****ting bricks when it happened last night. Moral of this story, don't be like me and hammer like a gorilla as you will most certainly break something. Of course it would have been simpler and easier if I had just removed the castle nut. The red you see is a little grease in the takedown pin channel. I always grease them to keep abnormal wear down. I also had to cut down the detent spring to compensate for the longer detent. I ended up using the shorter one as the longer half still made it bind up. Yep, I function checked it after hand tightening the castle nut.









The silver lining is that I was trying to close the takedown pin. Hindsight being 20/20 I'm glad I wasn't trying to hammer it open. Could you imagine how bad it would look if that were on the outside? Yeah, I'm still a little pissed off at myself, but it could have been so much worse.
 

·
Administrator
Joined
·
72,105 Posts
Rule #1 when taking apart or reassembling anything. If something doesn't want to budge DON'T FORCE IT. Stop and look at what the hell is wrong. I learned that lesson the hard way 25 years ago when I tried to disassemble an old Ford carburetor. I couldn't get the air horn off, assumed it was just stuck, and started prying on it. It wasn't until I buggered the snot out of it that I discovered there was a hidden screw that I missed. Thanks to my ignorance I managed to ruin a perfectly good, vintage 4-barrel carburetor and it cost me $400 to buy another one.
 

·
Registered
Joined
·
7,687 Posts
As my wise Father taught me, "Tight is Tight, Too Tight is Loose".
 

·
Administrator
Joined
·
72,105 Posts
On the bright side... that detent plunger is really easy to lube now. :D
 

·
Registered
Joined
·
831 Posts
Excellent post, RB. You don't see a lot of people willing to post anything more than a happy face, a thumbs up, and three dozen +1's any more. So I really appreciate the quality of your composition and your excellent photography. Well done from a neighbor just down the road in upper East Tennessee. We need more of this kind of participation in our hobby.
 

·
Registered
Joined
·
1,345 Posts
Discussion Starter #11
So did you actually figure out why it was stuck in the first place?
It must have been a burr in the detent channel. Once I removed the receiver extension I had to use a long small punch to drive out the detent. Once I drove it out it was smooth as could be. I did not see anything like a small piece of metal, but that's the only thing I could figure it was.
 

·
Registered
Joined
·
482 Posts
I did a similar thing once

To a Colt AR15 lower. This time it was removal of the selector switch. I was, as you were, sure I'd done it all and yet the switch would not easily come out. Thinking back I had to have been in a total brain fog. That is not the time to be doing anything to a firearm. I did get out the ballpeen and punch and sure enough, it did come out. After breaking loose a piece of the pin housing inside the receiver. At least it was not noticeable and I could '2 part Epoxy' it back. It did work fine once repaired. Of course from then on I'm thinking about that slight imperfection. But the firearm never malfunction, nor did the selector detent pin come loose.
Lesson learned the hard way, which is pretty normal around here.
Have a good one!
Oh...and since then I'm the guy who says, "If it takes more than a screwdriver it's not going to happen"...haha...well there are carefully considered exceptions now and then using a brass punch and plastic hammer...lightly as she goes
 

·
Registered
Joined
·
3,701 Posts
I liked your solution to the problem. I would have likely used JB Weld epoxy to fill in the damaged spot. Then drilled the out hole again. But your fix is good though.
 

·
Administrator
Joined
·
72,105 Posts
I just fixed the OP for you.
 

·
Registered
Joined
·
816 Posts
For years, I used to think the Delrin pin punch for takedown pins was a really dumb idea. But last year, I picked one up on impulse at a gun store, as I have an LMT lower - to VLTOR MUR upper gun that has a really tight fit on the rear pin. Now I am greatful that I have it. It doesn't marr the takedown pin, it's Delrin nature discourages me from whacking away at it with a hammer, and every time I think 'it will just be easier to give this a careful tap with a screwdriver' I am reminded that I have the right tool for this particular job.

I am very sorry for your mishap, but fascinated and appreciative of the fix.
 

·
Administrator
Joined
·
72,105 Posts
I think a lot of guys forget just how easy an AR lower is to break or damage if you're in a hurry, not paying attention or not using the right tools for the job. RazorBurn is lucky that he was able to figure out an effective fix. Some guys do things like break off the ears that hold the trigger guard retaining pin because they didn't adequately support them while driving the pin out. The end result is a ruined receiver. The AR may be a military-grade rifle, but in the end it's made of aluminum and you can't just solve every problem you face with a bigger hammer.
 

·
Registered
Joined
·
3,701 Posts
I think a lot of guys forget just how easy an AR lower is to break or damage if you're in a hurry, not paying attention or not using the right tools for the job. RazorBurn is lucky that he was able to figure out an effective fix. Some guys do things like break off the ears that hold the trigger guard retaining pin because they didn't adequately support them while driving the pin out. The end result is a ruined receiver. The AR may be a military-grade rifle, but in the end it's made of aluminum and you can't just solve every problem you face with a bigger hammer.
I don't know, a BFBH could work pretty well.

I remember reading a travel story about a woman traveling in China via motorcycle. She had bought a Chinese copy of the Russian copy of the German BMW/DKW flat twin. One time she had to stop in a small town to get repairs to the bike, and the only guy in the town who was a mechanic, only had a hammer for a tool, nothing else. He seemed to work magic with that hammer too.

Anyway my BFBH is used mostly for installing wheel bearings.
 

Attachments

1 - 19 of 19 Posts
Top