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Regal Beagal
February 18, 2006, 08:19
For almost an hour I tried to remove the pin form my Polish AK Barrel with no success using a heavy duty 6" steel punch and a 2lb hammer. Almost killed my hand a few times. I first tried to do it in the vise but I couldn't get enough leverage and enough swing due to having to strike the punch from the side. Next I clamped it to the work bench and some blocks, giving me more downward drive and force. It still didn't budge. I even ground the end of the punch down to more of a point hoping that the force would be directed more to the center of the pin. I don't have access to a press or the extra cash to buy a press. Any tricks out there that I haven't thought of? My buddie has one of the Romy kits and he was able to drive his out after some exerted effort. Of course, his was built in the early 90s and mine was manuftured in 1972. Would heating the pin do any good? RB

bykerhd
February 18, 2006, 09:56
A press is probably best. Since you don't have one or access to one ? Try clamping on to your punch with a pair of Vise Grip pliers. That allows you to hang on to the pliers instead of the punch so you can really wallop the crap out of the punch and not have to worry about hitting yourself. Amazing difference as most people tend to learn from painful experiences and tend to try not to repeat them, at some level anyway. Should your "remote control" punch fail, you could drill out the pin. Replacements are available from places like Arsenal Arms.

Merl
February 18, 2006, 10:34
pick up a 1/4" x3/4 grade 8 bolt and a pack of large washers. tape the washers to one side so there is a place for the pin to press out and the trunion is supported flat. put it in the vise and close the vise on the bolt to press out the pin. with luck the pin will break free before the vise breaks. once started you can either use a longer bolt and a couple nuts/more washers or the hammer.

I've not had good luck with trying to drive them out with a hammer, ended up just peening the pin some

Regal Beagal
February 18, 2006, 12:48
Merl,
I had thought about using the vise as a press just couldn't come up with a 1/4" pin and a way to support it. The #8 bolt is a great pin. I'll give it a try. If it just gets it to pop I'll be able to get it the rest of the way with the punch. I'll let you know how it goes. RB

sonnydazegunsmithing
February 18, 2006, 12:51
after youve got merls way set up and some tension on the vise hit the front of your vise with your two pound sledge and your pin should come right out

jamesq
February 18, 2006, 13:05
i'm not comfortable using a press under so much pressure. if the thing isn't perfectly square, stuff can fly out at 1000mph. really hurting whatever it hits. if you use a 'made in china' vice for this it might crack in half.
a good solid surface like an anvil and a grade 8 nut with a relief cut in the side to support around the pin and a 1/4" grade 8 bolt cut to 1" long (with the edge beveled) or just long enough to get the vice grips around it and not smash up the trunnion has worked out pretty well. it also helps to get a buddy to told the vice grips and steady the barrel or swing the hammer; depending on who's better at what. one or two good SOLID whacks does the trick usually. make sure you're using kroil or pb blaster to soak for a few days before attempting.

bykerhd
February 18, 2006, 14:48
I've done the vise and 1/4" grade 8 bolt on two AK trunnions. It worked, but it is kind of scary and there is no good retreat if something goes wrong.
Try the Vise grips on your punch. The idea of enlisting a helper is a good one. Sometimes anyway.

ftierson
February 18, 2006, 23:16
Originally posted by bykerhd
The idea of enlisting a helper is a good one. Sometimes anyway.

:)

Pretty funny...

Pretty true...

Sorry, couldn't help myself...

Forrest

ftierson
February 18, 2006, 23:24
By the way, I probably should mention that, of the last six Romanian AIM (AKM) G kits that I've worked on, two had barrel pins that wouldn't budge with a 12 ton press.

That's when it's a good time to know a really good machinist, so that the pins can be milled out... I do, and they were...

Forrest

XHardrock
February 19, 2006, 07:04
Originally posted by sonnydazegunsmithing
after youve got merls way set up and some tension on the vise hit the front of your vise with your two pound sledge and your pin should come right out

+1
I use a 2# rawhide mallet.

raeldridge
February 19, 2006, 09:01
so far, in my humble experience, if you meet three conditions you *will* get the pin to move.

--Secure Mounting. not gonna do it on a bench, on the floor, someone holding it, etc. get two blocks of wood, or better two pieces of hard plastic like the kitchen cutting board are, drill holes for the rivets. clamp into a 5" or 6" vise with the barrel pin barely above the level of the vise jaws. this allows you to use the vise as a 'rest' for the next step.

--Energy Transfer Device. also known as big honking punch. don't screw around with that smaller Sears Craftsman stuff. I have a 12" air hammer punch, inch square on the sides that tapers down to a point. I suspect you could get some 1" re-bar and spend time at the bench grinder and it will work as well, if you don't get it too hot and soften the metal. I wonder if you were able to grind it to 3/4" square and put a socket on it, with an apex bit something like that as a removeable head. don't know if that will take the force though without breaking.

--Energy Generating Device. also known as a big honking hammer. minimum three pound sledgehammer, preferably five if you're feeling manly.

rest the ETD on the jaw of the vise (see previous paragraph) against the pin, and whump it with the EGD. doesn't matter left to right or reverse. if *anything* moves other than the pin, i.e. barrel assy, vise, or bench, you've not fulfilled the first condition and you won't pop the pin. if it's secure, the pin will move. if you whump it good three or four times and you see no movement, or minimal movement, reverse it and whump it from the other side.

son and I darn near destroyed one trunnion getting the pin out, we finally took it to a machinest. I've done multiple other kits this way, it's 100%

pm or email me if you want pictures of what I've used.

Court in Fl
February 19, 2006, 09:51
I have had good luck useing a heavy duty air hammer to get out most AK barrel pins.

If it will not come out from one side than try the other side.

Good luck, Court in FL.

ProGunOne
February 19, 2006, 10:48
I tried the method described by raeldridge after attempting the use of a 12 ton press and pin holder tool that slides over the ram. The vise, hammer, and punch method worked like a charm.

Regal Beagal
February 19, 2006, 13:32
Barrel and Trunion- Score 1
Vise and Hammer - Score 0

Well, I tried the vise pressing method with a solid wack with the 2lb. hammer on the front of the press and the barrel and trunion won the battle. My 4" vise base couldn't take the abuse. I needed a new 6" vise anyway. I'll give it another try once I aquire a more heavy duty vise. After that I'll try the sledge hammer method. I'm not going to quit.... I'm not going to quit. I can do it....!

jamesq
February 19, 2006, 14:05
make sure you're wearing all the essential safety gear: crash helmet, welding gloves, protective cup, knee pads, and safety glasses.

Powderfinger
February 19, 2006, 14:39
You need HEAT. Then apply the Knock-ometer. (BFH) One guy here says that's the only way. I don't recall his handle but he said once he did 8 in about a half hour.

And IIRC, the pin is tapered. You are hitting the smaller end, right? :eek:

bykerhd
February 19, 2006, 14:41
I couldn't find any evidence of taper on the barrel pins of an AMD-65 and a Romy that I tore apart. I did drive them left to right, but on inspection there did not appear to be a taper to me or my micrometer. Could be my eyesight.

Powderfinger
February 19, 2006, 14:45
Could be my memory. I thought I had read that somewhere. My AMD-63 was matching # and the headspace checked out fine so I never had to drive that pin out on my 1 and only AK build (welded as per justashooter's advice and direction). I just eyeballed it and if it is tapered it is only a slight amount.

motosapien
February 25, 2006, 11:18
All of my kits have pushed out with my 12 ton press. But I did'nt do a romy yet.
The secret to getting a stubborn pin out is a non yeilding surface. Try setting the trunion on the concrete floor and use a big 1/4" punch and a hand sledge.

Once you get it loose, use a press or a vise to push it out the rest of the way.

Use kroil before hand.........

WJ-Polish Guy
February 25, 2006, 21:08
Well infidels this is how stuff gets done..

http://www.hunt101.com/img/374485.jpg

ProGunOne
February 25, 2006, 21:21
I don't suggest heat. The pins are not tapered, I know cause I measured them. I drove mine out from right to left. Doesn't matter. Chucked it up in a big vise with a couple of hardwood slats. Clamped it low in the vise so pin is just above jaws on vise. Used a Craftsman long tapered punch and a four pound sledge IIRC. Worked like a charm. I have the xebec barrel and pin remover/installer kit and tried it with the 12 ton press to no avail. I'm telling you it works.
http://img508.imageshack.us/img508/5029/xebecjigkit8vq.jpg (http://imageshack.us)

http://img508.imageshack.us/img508/5776/xebecjig9gh.jpg (http://imageshack.us)

ProGunOne
February 25, 2006, 21:33
Here's a couple with the barrel chucked up for pressing on trunion.

http://img114.imageshack.us/img114/5527/xbcjigonakbarrel6ro.jpg (http://imageshack.us)

http://img146.imageshack.us/img146/3227/jigonbarrel20ks.jpg (http://imageshack.us)

ProGunOne
February 25, 2006, 21:43
http://img239.imageshack.us/img239/6194/jignrec2jb.jpg (http://imageshack.us)
http://img239.imageshack.us/img239/7504/jignrec35th.jpg (http://imageshack.us)
http://img104.imageshack.us/img104/9475/jignrec38hx.jpg (http://imageshack.us)

ProGunOne
February 25, 2006, 21:51
And the Barrel Pin Press Adapters that you install on the ram of your press- sold by Tailgunner on the AK Files


http://img146.imageshack.us/img146/8595/barrelpinpressadapters3gs.jpg (http://imageshack.us)

radkoch
February 25, 2006, 22:04
I use my trusty rivet gun. I'm an aircraft mechanic so this is a tool I have for my job. Some of you may be able to use an air hammer/ compressor and it is the only way to remove barrel pins. An air hammer turned up all the way will knock the pins out as well. I use a rivet set that is designed to drive 1/4 rivets out after drilling them. I've done at least 30 barrel pins this way. At a build party I drove out 8 pins in about 2 minutes. As quick as they were handed to me they were removed. These were a mix of AMD's Yugo's and romanians. As for barrel pins as stated above they are not tapered and can be installed and removed from either side.

Para Driver
February 25, 2006, 22:12
Make friends with someone who has a press, most auto repair shops have one,,, who wrenches on your car?? use a drill bit shank as the push pin, you'll need one that is about 1/2" long and then 1" long to do the job...

it is easier putting them back, just freeze the barrel and the pin, and they slide in very easy..

ProGunOne
February 25, 2006, 22:13
Nice, Rick. I've used one like that before (Sioux?) I borrowed from trailer shop mechanic once. They use them in the trailer repair shop for fastening panels and many other uses on intermodal trailers. Very strong I will say. Mechanic at shop would work alone sometimes, call down to power shop and ask me to come down and help him buck rivets. :rolleyes: :uhoh: :eek: Noisy as hell but I'm sure it works like a charm. I used air hammer before in auto repairs to knock out ball joints and remove tie-rod ends, etc. Never replaced mine after it broke, don't do much car repair anymore. Have you tried to set rivets on a build with it yet? I seem to remember them jumping around a bit.

WJ-Polish Guy
February 26, 2006, 08:27
Originally posted by ProGunOne
.... I seem to remember them jumping around a bit.


High end airhammers have pretty good trigger control and more precise, cheap are on-off noise makers difficult to control precisely.
Anyway air hammers are crude tools but if press fails I would use them before pounding with the sledge...

freefalle7
March 12, 2006, 22:34
I just use my 12 ton press.

I have pressed out the pin on 3 Romy, 1 polish, and 3 yugo barrels with no issues.

I tried the hammer and it didnt work, I must have not been holding my face right:tongue:

The press is easiest for me:D

plus its safer for my fingers and ears:D

FREE

http://pic2.picturetrail.com/VOL965/4056977/8434974/133048185.jpg

Regal Beagal
March 13, 2006, 11:22
-The Saga Comes to an End-

Well, I finally ended up taking the barreled trunion to a machine shop on Friday, thinking the pin would have to be machined out. The guy looks at it and asks, "Is this an AK47 barrel?" I state, "Yep" He states,"Not a problem." I had to leave it with him over the weekend which wasn't any big prob for me. Well, he calls this AM with the good news. As he stated, "Not a problem." He was able to knock it out with his 40 ton press. His 12 ton wouldn't budge it. Halleluah! Now lets see if I can get the barrel out of the trunion. :rolleyes:

I plan on soaking the heck out of it with PB blast before I even attempt the feat. I'm hoping the I'll be able to sail through the rest of this build like a breeze. I'll let you know if I run up against any more stumbling blocks.

ftierson
March 13, 2006, 12:54
The good news is that the barrel usually comes out quite a bit easier than the barrel pin.

On the two Romanian AIMs that I had to have the pin milled out in because I couldn't budge it with a 12T press, the barrels came out reasonably easy. They were still tight, but not that bad using a 12T...

I hit the trunion/barrel interface quite liberally with Kroil or Liquid Wrench and let it soak for a while before pushing the barrel out.

And, as an aside, I'd personally rather have the pin milled out if a 12T press won't budge it than use a bigger press.

I'm not trying to say that the person using the 40T press on yours didn't do a good job or anything either. It just strikes me that having that much force available requires extreme care in supporting the trunion so that it isn't damaged in the process. Not all people know enough about AKs to use the right amount of care...

But that's probably just me...

Forrest

Regal Beagal
March 13, 2006, 16:55
Okay so the Saga doesn't end.... To find out my machinist has a personality after all. The 40 ton press doesn't exist and he was only trying to get my goat. Yep, he was a little suprised that I didn't make a crack at him on the phone when he told me. So, he did have to machine the cross pin out. Actually, what he did was bore it out leavng a thin wall of the pin left and left some steel at the bottom of the pin, then took a punch and drove it out. I can't complain, he only charged me $5.00 to do the job. I was expecting $20.00. So, it has all ended well with me only shelling out a little more to get this kit put together. Now, all I have to do wait for the receiver to materialize and I can proceed with the build. Thanks Again Folks for all of your help. I'll probably still need some more advice once I get rolling with the rivets.