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Old January 18, 2013, 04:33 PM   #1
s2thalayer
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AK riveting question

Since the scare happened, I bought kits while so many were looking for rifles. Ended up with a Bulgarian 74, Egyptian Maadi, and Hungarian AMD 65. All of which are kits. I found some blank receivers also. In the time I've been waiting for them to ship, I've done quite a bit of research and decided on bolt cutters for the riveting. Seems tothtools makes some great jaws for the cutters that turn out perfect rivets easily. If I can't get my hands on those, I'll just make my own.

However, I suppose they won't work on the trigger guard or the mag catch rivets. I've built several Saigas, so I know the trigger guards on those go on with bolts. I hear the argument against screw builds for AKs is that the screws can shear off under all the pressure. I can't imagine the trigger guard or mag catch is under all that much pressure. I would guess bolts would work just find for that area. Am I right on this?
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Old January 18, 2013, 07:53 PM   #2
Dfariswheel
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Yes. Button head machine bolts are extremely strong, and have a durable black finish.

Somewhere on the internet a few years ago, someone supposedly "mounted" an AK trunnion in the receiver using tooth picks and fired it, and it stayed put.

I've never heard of screw builds breaking bolts, because a bolt is stronger than most rivets.
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Old January 19, 2013, 01:17 PM   #3
s2thalayer
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Thanks.

I ordered the 3 kits with no idea how to start from a blank receiver. I've done a lot of Saigas though so I figured it can't be too hard.

Turns out it's a bit more complicated, but I bought a couple rivet sets, and i think I'll buy a screw kit, too. Might do a little of both or whatnot. I've never riveted anything before, and I don't know how to headspace or press a barrel, so I got to barrels pre-installed. Might end up having to screw the front trunnion, too. Just going to see what happens. I'll probably rivet everything later though.

I see a lot of hate everywhere on the internet for bolts/screws in AKs. So many say they're not safe and "it's your head next to the trunnion" yet through google searches, I've yet to see a single example of an injury or a broken rifle from a screw build. And in my opinion, from seeing pictures...once it's painted I don't really see a considerable difference.
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Old January 19, 2013, 01:31 PM   #4
Willie Sutton
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Yes. Button head machine bolts are extremely strong


Which is why things like jet engine cores are bolted together...


Rivets are CHEAP and LIGHT which is why they are used in AK's (cheap) and aircraft structures (both considerations)

Bolts are EXPENSIVE and HEAVIER which is why they are not used in aircraft structures, but this is why they are used in critical areas needing additional strength where weight is not an issue, and re-entry (IE disassembly) is possibly contemplated.

Bolts are just fine when you do not care about the cost, have back-space for the required hardware (washer and nut), and do not care about the cumulative weight of the additional hardware.


Willie

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Old January 19, 2013, 09:17 PM   #5
s2thalayer
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Hm. See, that's what I tend to hear. screws/rivets should be stronger.

However the rivet lovers come in and call all of them idiots....but like I said...still yet to see anyone hurt or complain about a screw build other than looks.

I wonder what adding some JB weld to some of the parts along with screws would create a greater amount of stability. I wasn't too confident about a receiver block I installed in a Saiga once so I covered it with JB weld then screwed it and it's extremely stable. I hear to use locktite also, but like I said...I can't imagine JB weld not helping.
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Old January 19, 2013, 11:05 PM   #6
Willie Sutton
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However the rivet lovers come in and call all of them idiots....


Find one who is an aeronautical engineer and not some yahoo and we can listen to their opinions. Otherwise I think we can safely say that if it's good enough for a critical application, it's good enough for a low tech one.

Of course, the correct stuff is probably not found at Home Depot.... You might need to visit Fastenall if you cannot visit Boeing Surplus in Seattle...

Willie

.
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Old January 20, 2013, 08:10 PM   #7
Dfariswheel
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Many of the better hardware stores will carry blackened steel high strength button head socket bolts or you can buy online:

http://www.boltdepot.com/Socket_butt...il_finish.aspx

For better strength, buy fine thread.
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Old January 21, 2013, 01:23 AM   #8
gizmo688
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Quote:
Find one who is an aeronautical engineer and not some yahoo and we can listen to their opinions.
You rang? A properly done rivet is almost always more sound than a bolt. The simplest explanation I can come up with is that bolts leave wiggle room, while rivets mold themselves to the hole, thus properly transferring forces. I'm not going to pretend I know anything about AK builds, but if it were my build I would play it safe and rivet.
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Old January 22, 2013, 10:49 AM   #9
5thShock
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The receiver was designed for rivets. It is not a jet engine and the attributes of bolts by themselves don't matter. A screw build is the trailer trash of Kalishnikovdom, if you build one spray paint it gold.
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Old January 24, 2013, 05:14 PM   #10
blfuller
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There are fixtures available specifically for riveting the trigger guards. If you don't have access to a shop press it will not do you much good.

What I would recommend is to use a plate inside the receiver where the 4 rivets would attach the trigger guard at the mag release. 1/8" flat stock works well.

Essentially size the plate to be the same footprint as the trigger guard. Transfer the hole pattern to the plate, drill and tap as required. I can't remember if the socket head cap screws used were #6-32 or #8-32 x .25. You may need to chamfer the sides slightly to clear the inside radius of the receiver. You may need to notch the plate in the area where the mag release is. Essentially match the contour of the selector stop and you should be good.

If the heads of the screw prevent fully tightening them to make full contact with the trigger guard, you can reduce the head diameter with a file and a drill. Chuck the screw in the drill and file until fit is correct. Use some cold bluing to touch them up. Degrease all threads and apply red loctite on all screws then tighten securely.

For the rearmost hole on the tang you can use a nut or get real fancy and use a PEM self clinching nut that is pressed into the sheetmetal.
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Old February 5, 2013, 05:51 PM   #11
TuxAir
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I riveted mine together except for the trigger guard. I fabricated a plate as mentioned above and used black socket head cap screws. There is no stress to speak of here and made for easy adjustment of the mag catch plate.(which I had to do twice to get the right thickness.)
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