Another AR Build Issue - Stuck/Broken Roll Pin

[etrain16]

Okay, so I've got a build I'm working on and I've run into a problem I've not run into before. I was installing the bolt catch lever and ran into trouble with the roll pin. It started normally and as I tried to further set the pin, it seems to have hit a brick wall and wouldn't go in any further. I tried tapping a little harder and only managed to flare the head of the pin.

I didn't have any spare pins, so I ordered a few online and got them today. I then went to remove the other pin, and that's where I really ran into a problem. As this is my first time trying to push that pin out, I came to realize that I couldn't get a straight punch into the hole coming from the mag well direction because of the flare in the lower on the side of the mag well.

So, I tried a few things - I tried using a small allen wrench that I could get in there, but couldn't get enough force on it without damaging the wrench itself. When that didn't work, I tried a small nail that I had filed the point off of, but that didn't work either. Next, I used a vise grip and grabbed the roll pin and then tapped the side of the vise grip with a hammer to try and work it out, but just as I thought I was making some headway, the pin snapped in two. Now I've got a partial pin firmly lodged in place and almost nothing to grab on to. My last attempt was to try and drill it, but the only bit I had that was long enough to let me get a straight shot (the drill chuck is too wide to get right up next to the lower, so any bit has to be longer than the lower), snapped the minute I started the motor. All this is starting to scuff up the finish and I want to put myself on hold before I do any serious damage.

So, I'm open for suggestions on how to get this partial, very stuck, roll pin out. I am pretty well equipped with various tools, I'm just running out of ideas that won't cause potential damage to the lower. I have a feeling one of the brilliant minds at NWFA will have a good solution for this problem.

Here are two photos - one from each side:

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[2A2Dend]

@etrain16

If you have a scrap piece of flat stock steel, longer than the distance from the front of the magwell, to the bolt release, 1/4" thick, on the thickness side of that, drill a (1/4-3/8") deep hole that will accept a shank of a drill bit for the appropriate size pin. Tape to protect the lower, drive the broken pin out.

The drill bit shank may break, so drive as straight through the hole as possible.
Better to use a long punch, but my idea may work

 

[Velzey]

You need this combo.

First thing is cover everything whackable with blue tape! So we don't ding it up anymore.

Stick the long pin punch in from the front, I use two different sizes sometimes. And tap. Takes two people when you get a tricky one like this. The long pin punch's are flexible. (but not to much) Enough to put a pencil under to hold it up off the rcvr.
Oh and I have found that I take the roll pin and polish a slight taper on the end first..Ease of entry.

 

[etrain16]

@etrain16

If you have a scrap piece of flat stock steel, longer than the distance from the front of the magwell, to the bolt release, 1/4" thick, on the thickness side of that, drill a (1/4-3/8") deep hole that will accept a shank of a drill bit for the appropriate size pin. Tape to protect the lower, drive the broken pin out.

The drill bit shank may break, so drive as straight through the hole as possible.
Better to use a long punch, but my idea may work

Good suggestion, I'll give that a thought.

You need this combo.

First thing is cover everything whackable with blue tape! So we don't ding it up anymore.

Stick the long pin punch in from the front, I use two different sizes sometimes. And tap. Takes two people when you get a tricky one like this. The long pin punch's are flexible. (but not to much) Enough to put a pencil under to hold it up off the rcvr.
Oh and I have found that I take the roll pin and polish a slight taper on the end first..Ease of entry.

View attachment 282097

Okay, that might work, though I may not have a long pin punch that's the right diameter. I'll do some looking through my tools and see what I can come up with.

As for the roll pin taper, that's a great idea. The replacement pin I bought is actually pre-tapered, so hopefully that one will go in easier once I get this bugger out.

 

[jbett98]

Sell me the lower and start with a new one.

 

[ZA_Survivalist]

With a steel punch and some wiggling of yhe BHO, could you back out the jammed roll pin from the other side?

*Edit, someone beat me to it in the comments.

Edit #2.. Or should I say, someone beat me to the "punch"

 

[308]

Blue tape on the receiver (while assembling) is your friend...just saying'

 

[etrain16]

With a steel punch and some wiggling of yhe BHO, could you back out the jammed roll pin from the other side?

*Edit, someone beat me to it in the comments.

Edit #2.. Or should I say, someone beat me to the "punch"

I actually did try something similar to that - before I posted this - the biggest issue is that I can't come straight at it from the other side, I don't know if I described it well - so here are 2 more photos showing why getting a straight punch in from the other side is tough - the flare on the outside of the magwell gets in the way.

Velzey's idea suggests a "long" punch, something that is somewhat flexible - that may work, but I'm not sure yet if I've got the right tool for that. I've got some digging to do.

(Sorry for the out of focus photo)

 

[etrain16]

Blue tape on the receiver (while assembling) is your friend...just saying'

Yep, I had heard that before, but forgot to do it on this build. Always new lessons to learn - some harder than others

 

[jbett98]

Your best friend is a roll pin punch starter set. Well worth the $12.00.

 

[etrain16]

Your best friend is a roll punch starter set. Well worth the $12.00.

I've seen them, but haven't invested in one yet. I've got a regular roll pin punch set and a set of flat pin punches too. Probably time to get one of those starter kits next. Always more money to spend.

 

[MilitantBEEMER]

I was recently helping a friend build his first lower, and we ran into the same problem. I used a long small punch from the front and worked the damaged pin out. The only difference is I cannot remember if his lower had that flare? Good luck, it is an addictive adventure... Oh and in case you haven't heard it enough... BLUE TAPE

 

[jbett98]

Harbor Freight sells a nifty set of transfer starter punch's that have a dimple on one end.
Once you start the roll pin, the little dimple helps keeping the punch from wandering while the roll pin is being driven into the hole.
I also use these as a blind pin while installing triggers and hammers.
The long length also keeps you from wanging the lower.

 

[JayDub]

Google up "bolt catch punch" and ditto on the blue tape, cuts down on the "apprentice marks".

 

[2A2Dend]

I've got two extra sets of armory issue punches, 9 piece I believe. I would trade someone a set, for a set of quality roll pin punches.

Thought to toss it out there.

 

[Kruel J]

I had a similar experience with the trigger guard. Yep, installed the winter trigger backwards. Anyway, I VERY carefully drilled it out. Slow and low. Not a scratch on the receiver.

 

[etrain16]

Harbor Freight sells a nifty set of transfer starter punch's that have a dimple on one end.
Once you start the roll pin, the little dimple helps keeping the punch from wandering while the roll pin is being driven into the hole.
I also use these as a blind pin while installing triggers and hammers.
The long length also keeps you from wanging the lower.


View attachment 282102

Looks like I may need to swing by Harbor Freight on the way home tomorrow

 

[etrain16]

View attachment 282101
Google up "bolt catch punch" and ditto on the blue tape, cuts down on the "apprentice marks".

Interesting, never seen that before, looks like yet another tool to add.

 

[jbett98]

There only $11.99 for the set and they are handy for all kinds of uses.
And, they do work as advertised when transferring a starting center when drilling a pattern hole.

 

[etrain16]

There only $11.99 for the set and they are handy for all kinds of uses.
And, they do work as advertised when transferring a starting center when drilling a pattern hole.

Yeah, I think you sold me on that set. It starts at 3/32", which is exactly the size I need - at that length, I may just be able to get enough flexibility to get around that bump out in the mag well. I pass by HF on the way home from work.