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View Full Version : The dreaded blind hole rollpin removal...


Skadoosh
June 26, 2012, 10:39 AM
A friend of mine (NOT me) just made a huge blunder by installing a roll pin into the front trigger guard hole on his AR15 lower. He is not sure how to remove it.

Because it is a very small diameter roll pin, the only thing I can think of is to basically drill it out.

Any suggestions?

dahermit
June 26, 2012, 11:35 AM
Depends on how small. A tap small enough to turn into the center of the roll pin. However, as the tap screws in and forms treads, it will expand and tighten the roll pin against its hole.
Another thing worth a try, is to blow high-pressure air into the hole. I have had chips come out of a blind hole with enough force to cut the skin. So apply the appropriate cautions.
One other thing that might work, is to pour melted Cerrosafe into the hole. If the roll pin is not bottomed, it may go through the pin and get some purchase on the off-side of the pin. You would need to build up a "collar" around the hole to build up an amount of Cerrosafe to grip with pliers.

brickeyee
June 26, 2012, 12:16 PM
A tap small enough to turn into the center of the roll pin. However, as the tap screws in and forms treads, it will expand and tighten the roll pin against its hole.

Use a left hand tap.

Drilling will be a real chore since roll pins are spring hard.

A left hand carbide bit might have a chance.

oneoldsap
June 26, 2012, 01:51 PM
Doesn't matter if you use a lefhand bit or a righthand bit , neither the pin or the hole are threaded , and the pin is just going to spin anyway . I'd try to find a screw small enough to screw into the center of the roll pin . Then pull it out by the screw . Give your friend a good smack in the forehead , and tell him not to attempt things that are over his head ! ;)

dahermit
June 26, 2012, 03:24 PM
I'd try to find a screw small enough to screw into the center of the roll pin . Then pull it out by the screw . That is the idea I had with the tap. However, a tap is hard and would likely end up broken off. Your idea is better in that the screw is less likely to break.

saands
June 26, 2012, 03:29 PM
I like the idea of a small screw. You might even consider tapering the end, so most of your purchase will be at the very outer end of the pin.

As for drilling, I don't know if you were thinking of drilling the pin itself, or the back side of the trigger guard. Drilling the pin will not likely go well. Drilling through the back side, however, might buy you access to the pin to push it out. A really small hole, drilled slightly off center, might be just the ticket ... but it would be last resort kind of ticket.

Saands

Skadoosh
June 26, 2012, 03:40 PM
I think the screw idea might work but its an awfully small roll pin. I don't know where he'll find one small enough....

I am going to see if can send me a picture of it (he's in Florida and I'm in Virginia)

saands
June 26, 2012, 03:53 PM
Tapering the end of a #2 screw might get in there ... a 0-80 would almost certainly fit in ... 0-80 is only 0.060" in diameter and that is a .125 or so hole.

mapsjanhere
June 26, 2012, 03:59 PM
use epoxy glue and an appropriate thickness wire, you got lots of surface area that way to get plenty of traction

Skadoosh
June 26, 2012, 05:03 PM
I talked my buddy through the screw idea via Skype.

No joy.

Apparently roll pins are EXTREMELY hard...and very good at staying secured in place. No screw was able to get a good enough purchase to remove the roll pin.

So I asked what the trigger was made from. Joy of joys, it was a plastic trigger guard. After a quick discussion, I suggested that he sacrifice the trigger guard in order to exposed the rollpin.

My buddy went to his local hardware store and bought an 1/4" chisel for $8 and in a second Skype session that lasted all of 5 minutes, we had the trigger guard chiseled off, the roll pin exposed and a needle-nose Vise-Grip pliers locked onto the roll pin. A few taps on the Vise-Grips with the hammer and the roll pin was out.

My buddy sent these from his iPhone:
http://i43.servimg.com/u/f43/12/63/91/01/img_5814.jpg

http://i43.servimg.com/u/f43/12/63/91/01/img_5815.jpg

James K
June 26, 2012, 08:43 PM
It would have been easier to just drill a hole in the left side and drive the roll pin out from that end. Doing that wouldn't even interfere with reinstalling the plunger and spring if wanted unless the shoulder was drilled out of the hole to install the roll pin in the first place.

Jim

HiBC
June 26, 2012, 11:40 PM
OOps!I posted this after problem solved.I will leave it up,works with a metallic guard.I have made the same mistake.Slow down!!

Good news,absolutely no damage need be done to your lower.No drilling,tapping,etc.

Order another trigger guard and pin.

The Blind hole is actually only drilled through one side,the other tab has no hole.
So,the trick is,the dremel abrasive cutoff wheel.I use a Foredom motor.You slice the corner off the trigger guard,cutting through the pin.This would be slicing off the corner you drove the pin into.You are only cutting the ejection port side corner off the trigger guard bar,and cutting the pin as you do it.Wear eye protection,put the lower in a vise,use both hands to keep your die grinder stable,and watch what you are cutting.If you want,slip a piece of feeler gage between the guard and the mag well as a shield.Be very carefull not to cut into the mag well.Once that corner is free,the rest of the guard will swing down,and then the corner and pin can easily be removed.

brickeyee
June 27, 2012, 11:46 AM
Doesn't matter if you use a lefhand bit or a righthand bit , neither the pin or the hole are threaded , and the pin is just going to spin anyway .

you are aware there are more than a single style of roll pin?

A left handed tap is likely to grab the inside of the roll pin, and it is is a spiral style pin not expand it further.

Even a left handed drill bit might get enough bite to allow the pin to be pulled out.

An actual tap would still be the best option.

A tapered screw may expand the pin even tighter, making removal that much harder.

Gunplummer
June 27, 2012, 09:09 PM
Was it a roll pin or a spring pin? A lot of people do not know the difference and inserting a spring pin into a roll pin application can really ruin your day. Just general info.

samcolt1860
June 28, 2012, 07:54 AM
Skadoosh,

Originally you said your friend was having a problem with the FRONT pin, which is a spring and plunger, but the photos show that he chiseled off the the REAR of the trigger guard to remove the roll pin. :confused: BTW, I checked both of my AR 15 lowers (a PWA and a Spikes) and the rear roll pin hole is not a blind hole.:confused: