OK I'm a noob & and idiot: epic bullet guide failure

[bws1 58]

I know this topic has been flogged to death but I have nowhere else to turn.

 

I've been lurking around this and a couple of other forums, hoping to gleen some advice before I lose my mind.

 

Using a drill press, the hole was a breeze. The tapping, on the other hand was nothing short of a f-ing tragedy. I've gone through 4 taps: (2) 6-32's and (2) 8-32's. Before you rake me over the coals, I did all of these by hand, I used cutting oil and I would reverse a half turn when I'd feel the teeth start to bind up. Needless to say the trunion is a bit of a mess. After reading through damn near everything I can get my hands on, JB Weld isn't going to be an option, so I'm left with three alternatives:

 

1) Take it to a shop that can do EDM and have them burn the last tap out and have them weld it

2) Swallow my pride, take it to a gun smith and be the butt end of a joke for a few years

3) Pound out the last tap and go up to a 10-32 screw.

 

My gut tells me #3 could work but I might be better off doing the two former options. My biggest concern is safety (for others and myself), then reliability.

 

Thanks in advance for any advice

[Mullet Man 2,114]

You have more then 3 options...

You can get a TiN coated tap (about as tough as it gets) and try that but it will cost about $25 from Fastenal.

 

Another option is join a site like AK files or the likes and find some local guys who are able to press rivets and hookup with them somehow.

 

One other option is to nut and bolt it in place (use 8-32 hardware), which i have read of some folks doing on here. Might be a little tricky but it should be doable.

 

A competent welder can handle it to. (last resort IMO)

 

Always exhaust all options with the smaller fastener first before stepping up to a larger hole.

 

Edit; Sometimes it's good to put things down for a day or two and regroup. No big deal.

Edited January 2, 2013 by Mullet Man

[chevyman097 2,579]

Is the tap broke off in there?

 

 

What mullet suggested is pretty much best.

 

 

If the tap is broke off you can try to drill it out and remove it. Open the hole up a little and re tap it. Dont be afraid to go heavy on the cutting oil, and dont go cheap on a tap. Slow and steady is the key, by all means dont rush it. When I mean slow, turn it millimeters a second.

 

I have heard of some riveting but you have to have the right tools. Welding it in is an option but dont get a bubba weld. You can fubar the receiver in no time.

[bws1 58]

"Edit; Sometimes it's good to put things down for a day or two and regroup. No big deal."

Mullet, thank you for the perspective and yeah, I've put it down and left it alone for a few days.

[bws1 58]

Is the tap broke off in there?

 

 

What mullet suggested is pretty much best.

 

 

If the tap is broke off you can try to drill it out and remove it. Open the hole up a little and re tap it. Dont be afraid to go heavy on the cutting oil, and dont go cheap on a tap. Slow and steady is the key, by all means dont rush it. When I mean slow, turn it millimeters a second.

 

I have heard of some riveting but you have to have the right tools. Welding it in is an option but dont get a bubba weld. You can fubar the receiver in no time.

Chevyman,

 

Oh yeah, the last tap is still stuck in there, with maybe 1/4" protruding from the trunion. I was thinking about grinding it flat and blow another 15 bucks on some diamond dust dremel bits, but after the futility of the first couple of attempts, there's no way in hell I'm going to be able to drill that thing outta there. I wasted a couple of good cobalt bits trying to drill the taps out, but those suckers were hard and I was afraid I'd ultimately wind up damaging the breech if any of the bits snapped.

 

Given that these things are cockroach tough, I could wail away on it and shatter it but I don't want to press my luck. I know these suckers are rugged weapons but they do have limits.

 

Thank you for the reply!

[Mullet Man 2,114]

Shattering it is about the only way you're gonna get it out, short of standing over a drill press for a couple hours while it wittles away. It's punch and hammer time, give it a sharp whack, you won't hurt anything, just don't miss.

 

They are hardened, they have to be harder then the metal they are tapping. They are also brittle, which is why they break kind of easy. Being brittle helps in being able to shatter them when they break.

[mancat 2,368]

Good suggestions.. When you get to tapping it again, you want to back out the tap each time and clear the threads with compressed air. Unless you did this, it's probably why your tap broke. Even though it's a small hole, you still shoud clear out the threads as you go.

Edited January 2, 2013 by mancat

[bws1 58]

Folks, all awesome suggestions and thank you! But I need to follow up with another question: Since I'm actually reluctant to make the opening any larger than what's required to hold a 8-32, can I shatter the tap and make use of the already cut threads, by inserting a heliocoil (sp)?

 

Thank you again, this is very valuable information!!

[mancat 2,368]

You may be able to just continue cutting the previous threads by carefully chasing them with another tap.

[Mullet Man 2,114]

Inserting a helicoil is way beyond what is needed to potentially get the job done. If the threads are no good after shattering the tap, i would seriously look at getting a 20-30¢ 8-32 nut and fastening it that way. You will be able to access the screw with the handguard removed.

 

If it was an aluminum head in a car with a stripped spark plug threads, then i would look at a helicoil. But IMO, for something like this...looking into a helicoil is a bit goofy.

Edited January 2, 2013 by Mullet Man

[bws1 58]

Thank you all very much! I'll give this another try in a few hours. Now that I've had a couple of days to step back and not think about it (best advice ever, btw), I'm itching to get back into it.

 

Cheers

[thebuns1 4,323]

You may be able to just continue cutting the previous threads by carefully chasing them with another tap.

This is what I would try before going one size bigger. If your tap is broken off with about a 1/4" exposed, you may be able to take some vice grips to it and back it out, and use a new tap. If not just shatter it like suggested if it breaks off down inside the trunnion. Did you drill your hole all the way through the trunnion? I do incase it breaks, I can just shatter it and let it fall out.

 

I always blow the holes out after every insertion. (Chevyman, thats your que lol), but it helps keep the hole clear from debris and puts less stress on the tap.

[bws1 58]

OK I have a new and profound respect for soviet bloc weaponry. It took me about 20 minutes of gentle persuasion, shattered the old tap, blew it out with compressed air, ran a pipe cleaner through and then ran a sacrificial screw through a few times. With a little red loc-tight that sucker ain't going anywhere. Thanks ya'll.

[Mullet Man 2,114]

Good deal. We like to say that AK's are built out of scrapped Russian tanks.

Edited January 3, 2013 by Mullet Man

[Paulry 50]

Next time, lighten up on the cutting fluid and apply more Whiskey!! Don't forget to lube that Avtomat!!

 

Ya, most of us have been there at one time or another. For many it was on a car or truck, maybe an RV??? At home or at work. It makes it hairier when it is fine Russian weapon!!

 

Good job!