Easiest AK build EVER.

Thanatos · 01-02-2006, 01:42 PM

A couple of months ago I did my easiest build ever. Over on gunco.net we used to talk about using "type U drive screws" to do a build, but no one ever got around to doing one that I know of. Well a couple of months ago I got access to about a dozen of the drive screws and I had a kit at home unbuilt so I said "what the hell" and went to work. All it involved was grinding the rivets flush and drilling the appropriate size holes then pressing the drive screws into the holes. No headspacing, pulling of the barrel or removing the rivets. I used the drive screws for 4 of the trunnion holes, the center support, and the rear tang. I did end up using screws for the 2 rearmost trunnion holes because I removed the rivets and the holes were too big for the drive screws I had, but I am sure I could have used drive screws if I had bigger ones. Yesterday I finally got the opportunity to test fire the build and it ran like a clock. I fired about 300 rounds through the rifle with no adverse effects on the drive screws. This would be the ideal build for guys with limited tools.

fraxxian · 01-02-2006, 02:34 PM

so are these some sort of self tapping screw?

The_Weasel · 01-02-2006, 03:08 PM

Looks pretty cool - I'm game - where do you get these and what size are they? Do they require any special prep work???

Thanatos · 01-02-2006, 03:32 PM

Apparently you can get them from Mcmaster/Car (sp?) or just google "type u drive screw" and you will find lots of sources. The only prep work these require is grinding the rivets flush and drilling the appropriate size hole for your drive screw. I think the ones that I used were #10. They are like a rivet that are self holding and don't require any tapping of holes or any barrel pulling. Apparently I am the second one to do this as WinnR on gunco.net did one in June with great success as well.

Mandaree36 · 01-02-2006, 04:00 PM

U-Drive screws are round head metallic drive screws having multiple start threads of large helix angle, with a pivot. Featuring case-hardened threads, designed to be harder than the mating part, The Type U-Drive Screw is used when an attachment is not meant to be removed. It is driven into an undersized hole for great adherence, usually in metals or plastics. U-Drive Screws also have a round, unslotted head, again intended for a permanent fixture.

Sounds like something I want to try.

Some info on sizing of holes to screw size, etc at this site:
http://www.americanfastener.com/fast...elftapping.asp

jwolf74 · 01-02-2006, 06:02 PM

Anyone having more info on this type of build please share with us. What size you used , etc....

mj2evans · 01-02-2006, 08:21 PM

Do you hammer these in or pressed like a regular rivit? Could you use this in tjhe front trunion without removing the barrel?

Thanatos · 01-02-2006, 08:33 PM

When I did my build I removed the receiver stubs from the trunnion, tang and trigger guard. After removing the receiver stubs I simply ground the rivets flush with the trunnion and rear tang, marked center of the rivets and drilled holes for the drive screws. I determined the size hole I drilled by measuring the small end of the drive screw and using the appropriate size drill. I believe the drive screws I used were a #10, but I don't remember the size hole I drilled. For the rear tang I used the drive screws full length, but for the trunnion I ground them off to about .240" because the holes I drilled were only .244" and the drive screws were .250". I then put my parts into my receiver and used my hydraulic press to set the drive screws. The reason I used my press was that I was afraid that I might start one crooked or wreck something swinging a hammer, although I am sure you could use a hammer if you were careful. I could only use 4 of these on the trunnion because after I ground the 2 rearmost rivets flush I pushed the rivets out and my drive screws weren't big enough to use on the holes left so I used some grade 8 10-32 screws I had left over. For the center support I used my usual length of 1/4" stainless tubing and drove a drive screw into each side to hold it in place. For the trigger guard I used nuts and bolts.

d.hauser · 01-05-2006, 03:27 AM

i deal with mcmaster-carr alot at work, so i checked out the drive screws. they come in bags of 100 if i under stood the description right, and they are cheap. i have three kits to build and i now plan on using this method of assembly. but i wont need all of the drive screws. so if you guys are interested maybe you could send me a self addressed padded envelope and like a buck...lol, and i will send you the drives screws you would need. i need to figure out the correct sizes. they have steel and stainless ones. let me know..................

spraynpray · 01-05-2006, 06:54 AM

Very impressive, I imagine that along with everyone else we would be inteered in a "kit" of these that would press into the trunion holes. I already have a couple of kits with the rivets removed and so they would need to go directly into the trunnions. The look and hold of rivets without all of the hassle.

d.hauser · 01-06-2006, 03:41 AM

ok once i actually get my kits, they should be here next week. i will figure out just what size we would need. i will then get the drive screws and figure out how much it would actually cost for a set. then if any one wants i`ll give my address and you guys can send me the actual amount, plus for the padded envelope and shipping. i have a press but i was thinking on making a concave type of drive punch and just use a hammer to set them.

spraynpray · 01-06-2006, 09:21 AM

It might be interesting to see if one of the bolt cutter rivet crunchers would drive them in. The punch idea seems very logical.

6526 · 01-06-2006, 09:47 AM

Quote:

Originally Posted by spraynpray

It might be interesting to see if one of the bolt cutter rivet crunchers would drive them in. The punch idea seems very logical.

I think I'd use a bit of silicone or graphite lube on the head for that to encourage rotation. Are these critters hard enough to bite (thread) into the trunion itself? Does anyone know what the Rockwell hardness of of the trunion usually is? thanks

lpspinner · 01-06-2006, 02:48 PM

Would you/Could you add some Red Loctite? Do the have a larger size for the rear that would fit the existing hole left over when the rivet falls out?

mj2evans · 01-06-2006, 11:46 PM

d. hauser - I would throw in a buck or two for a couple of screws to play around with.

Tilton Hilton · 01-07-2006, 12:01 AM

I'm also very interested in hearing anything additional regarding this method.
Jim

sct1886 · 01-07-2006, 10:05 AM

Quote:

Originally Posted by d.hauser

i deal with mcmaster-carr alot at work, so i checked out the drive screws. they come in bags of 100 if i under stood the description right, and they are cheap. i have three kits to build and i now plan on using this method of assembly. but i wont need all of the drive screws. so if you guys are interested maybe you could send me a self addressed padded envelope and like a buck...lol, and i will send you the drives screws you would need. i need to figure out the correct sizes. they have steel and stainless ones. let me know..................

Pm'd you no answer. Please send contact info. scottbattlesREMOVE@juno.com

gaucho1 · 01-07-2006, 03:54 PM

Quote:

Originally Posted by d.hauser

ok once i actually get my kits, they should be here next week. i will figure out just what size we would need. i will then get the drive screws and figure out how much it would actually cost for a set. then if any one wants i`ll give my address and you guys can send me the actual amount, plus for the padded envelope and shipping. i have a press but i was thinking on making a concave type of drive punch and just use a hammer to set them.

PM sent
Thank You

tanlover442 · 01-07-2006, 05:24 PM

wow...

....now this is one heck of an idea!!!

this selfsetting rivit idea would be fantastic!!!

lets hear from someone who has built one and had it working for awhile.

cntrailrider · 01-08-2006, 02:43 AM

I like this idea. You have my attention -

Steve in El Paso

Wrangler · 01-08-2006, 09:30 AM

Hi, I just ordered some 8s and 10s from Mcmasters. Should have them this next week. It would be interesting to try them.

Wrangler · 01-08-2006, 09:32 AM

Just for the record I am another West Texan (native).

tanlover442 · 01-08-2006, 11:01 AM

Wrangler..........howdy pardner

tanlover442

cntrailrider · 01-08-2006, 01:29 PM

Wrangler - email me direct cntrailriderNOSPAM@msn.com

I cannot send PM's on here anymore for some reason.

Steve

xuanloc69 · 01-08-2006, 08:45 PM

I'd like to try it. Can you send me enough for 2 builds?. How much & where to? Thanks.

Mandaree36 · 01-09-2006, 12:20 AM

Wow this thread is growing. I am in too. PM with your contact info - I want to try these as well. Damn and I just got my rivet kits...oh well I guess I will have to build more of each...you know for evaluation purposes....

Bruce R. · 01-09-2006, 10:24 AM

I hope you realize that these pins are for location, and don't supply any reliable clamping force. If and when they back off, even a little, you lose all the integrity of the joint. Hammering them back will not help because you will have lost the fins on the shank of the pin, and that's what holds these things in place. Both rivets and screws work because they are under tension and act like springs to an extent, you don't get that action with a drive pin. I think you are making a mistake by trying these pins, and I hope you don't get hurt when they start to loosen up.......

robdog · 01-09-2006, 10:31 AM

I agree with Bruce, There is a reason that rivets are still used to this day for building AK's. Superior holding power. If it aint broke dont fix it. Stay with the tried and true method that has worked for 50+ years.

lpspinner · 01-09-2006, 12:15 PM

Back to my original question...

What if you use the drive screws with Red Loctite? Wouldn't that help?

JohnFreeman · 01-09-2006, 12:27 PM

Quote:

Originally Posted by Bruce R.

I hope you realize that these pins are for location, and don't supply any reliable clamping force.

Hi,

I'm following this thread, and am interested in your statement. Do you know that they are designed not to provide clamping force? I have looked for application notes for these and have not been successful.

I'm neither encouraging nor discouraging use of these, but the idea in an interesting one. Why would you claim that they're not to provide clamping force? Let's forget for the moment whether they will, or will not, back out.

Would seem to me that the only significant load on the rivets in an AK (at least front and rear trunion) when shooting, are shear loads parallel to the axis of the barrel, not tension or compressive loads which would perpendicular to the axis of the barrel

Rgds
John

Oregon-Jet · 01-09-2006, 06:37 PM

Quote:

Originally Posted by JohnFreeman

Hi,

I'm following this thread, and am interested in your statement. Do you know that they are designed not to provide clamping force? I have looked for application notes for these and have not been successful.

I'm neither encouraging nor discouraging use of these, but the idea in an interesting one. Why would you claim that they're not to provide clamping force? Let's forget for the moment whether they will, or will not, back out.

Would seem to me that the only significant load on the rivets in an AK (at least front and rear trunion) when shooting, are shear loads normal to the axis of the barrel, not tension or compressive loads which would perpendicular to the axis of the barrel

Rgds
John

I too would be interested in this as well, any info on the screws?

VaFisher · 01-11-2006, 05:47 AM

Bump

Bruce R. · 01-11-2006, 05:59 AM

This may come across as insulting, it is not meant to be in any way, shape, or form.
These drive pins are used for things like attaching name plates to motors and equipment. You have seen them used that way I'm sure. They are probably what's holding the data plate on many of the hydraulic presses we use. How many times have you seen a loose name plate on a piece of equipment or a motor?
In order to provide clamping force you have to stretch the bolt, screw, or rivet by some method. These drive screws can't be stretched because they are hammered in from one side. In point of fact, they get compressed when hit, and then spring back just about guaranteeing that they will not be tight. No matter how tight you think you have them, all it takes is a few shock loads and there will be movement, and there is no way that you can re-tighten, even if you try to hammer the pin back in. All that will happen is that you will wear away the "fins" that are providing the friction that holds the pin in place. These drive screws are NEVER used in critical installations because they can't be relied on to hold anything together tightly.
I have been looking through all of the major suppliers catalogs for some data to back up what I have stated, but so far I can't even find a manufacturer of the pins. However everything I have found is limited to name plate attachment and light duty fastening where an ALUMINUM pop rivet will do the same job. It's certainly not my place to tell anyone what they can or can't do, after all it's their rifle, and their head and eyes, but I think that a bit more research is called for before we jump to the conclusion that any fastener will work to build an AK. If that were the case we could use ordinary hardware store screws, or even aluminum rivets to hold these things together. I would respectfully ask if anyone here has ever seen these fasteners used on any centerfire firearm, ever,….. I know I haven't, and if they are useful and will work, particularly in a stress location, don't you think some one, some where, would have used them?
"Would seem to me that the only significant load on the rivets in an AK (at least front and rear trunion) when shooting, are shear loads normal to the axis of the barrel, not tension or compressive loads which would perpendicular to the axis of the barrel."
That's not entirely accurate. If you saw the very slo-mo photo's of the AK being fired on the History Channel a while back, you might have noticed that the receiver bounced and flexed as if it were made of rubber. There are forces going in all kinds of directions. I once thought as you do until I saw that film, the loads were clearly not only in shear. You might also have noticed that some of the rivet holes are counter sunk into the trunion. When the rivets are pressed in place, they force the sheet metal of the receiver into that countersink adding significantly to the shear strength of the joint, while not transferring that load to the rivet, instead a tension load is applied because of the sloped angle of the two pieces.

Thanatos · 01-12-2006, 08:06 AM

Bruce, thanks for the pearls of wisdom, but I know for a fact that there are drive screw builds out there with cases of ammo through them with no failures. I also have a slow motion video of an AK firing full auto with the dust cover removed and I can't say that I notices any "rubber-like" tendencies associated with the receiver. While I appreciate your commentary, I am very confident that this is a very feasible option for the home builder. Although I believe this is a great idea that I wanted to share with the community, if you have ANY doubts about the integrity of these fasteners, please DO NOT build this way. And if you do build this way, do like I do with every firearm I shoot: Always be looking for any type of abnormality with the firearm, and inspect it at regular intervals. With my drive screw build I checked it after every few rounds when I first shot it, now I check it less often.

Here is a link to the slow motion firing of the AK. I don't see any of the dramatic flexing that you talk about. Full auto AK in slow motion.

Bruce R. · 01-12-2006, 04:18 PM

As I said before, these are your rifles, and you can build them any way you want to.
I have reviewed once again the History Channel footage, and the flexing of the receiver is obvious. For what ever reason I can't seem to pull up the web site you mentioned, so I can't comment on it.
I also went to the web site mentioned in Bubbajj's post:
http://www.sksboards.com/forum/view...p?p=94952#94952
There is some obvious mis information there. The type U drive screw is shown in doneking's post to be deformed after being driven into a hole. That seems to me to be unlikely because the screw is supposed to be hardened to the point that the fins bite into the base metal of the bored hole. It's highly unlikely that you can have it both ways, that is hard enough to bite into a hardened trunnion and soft enough to deform when it strikes the barrel.
Again, all I can say is that I have never seen these "screws" used in any high stress location, and I certainly will not take the chance of finding out.
Best of luck with your build, and I promise I'll say I was wrong, and you were right when you put 10,000 rounds through your gun without a failure as they routinely do with rivet and screw builds.

01-02-2006, 03:08 PM	#3
The_Weasel Member AKaholic #: 3868 Join Date: May 2005 Posts: 450	Looks pretty cool - I'm game - where do you get these and what size are they? Do they require any special prep work??? __________________ Eagles may soar... but Weasels don't get sucked into jet engines...

01-02-2006, 03:32 PM	#4
Thanatos Member AKaholic #: 2620 Join Date: Aug 2004 Location: Omro, WI Posts: 126	Apparently you can get them from Mcmaster/Car (sp?) or just google "type u drive screw" and you will find lots of sources. The only prep work these require is grinding the rivets flush and drilling the appropriate size hole for your drive screw. I think the ones that I used were #10. They are like a rivet that are self holding and don't require any tapping of holes or any barrel pulling. Apparently I am the second one to do this as WinnR on gunco.net did one in June with great success as well. __________________ A village in Massachusetts got their idiot back.

01-02-2006, 04:00 PM	#5
Mandaree36 2nd Class Member Platinum Contributor AKaholic #: 4562 Join Date: Oct 2005 Location: North Dakota Posts: 14,470	U-Drive screws are round head metallic drive screws having multiple start threads of large helix angle, with a pivot. Featuring case-hardened threads, designed to be harder than the mating part, The Type U-Drive Screw is used when an attachment is not meant to be removed. It is driven into an undersized hole for great adherence, usually in metals or plastics. U-Drive Screws also have a round, unslotted head, again intended for a permanent fixture. Sounds like something I want to try. Some info on sizing of holes to screw size, etc at this site: http://www.americanfastener.com/fast...elftapping.asp __________________ CENSORED.. I wont check my religious beliefs at the door....to accomodate you - nor will I apologize for them... We do not ask for your poor or your hungry. We do not want your sick and tired. It is your corrupt we claim. It is your evil that will be sought by us. With every breath we shall hunt them down. Each day we will spill their blood. ‘Till it rains down from the skies приедьте и получите некоторых Вы трусы Last edited by Mandaree36; 01-02-2006 at 04:06 PM. Reason: found more info

01-02-2006, 08:33 PM	#8
Thanatos Member AKaholic #: 2620 Join Date: Aug 2004 Location: Omro, WI Posts: 126	When I did my build I removed the receiver stubs from the trunnion, tang and trigger guard. After removing the receiver stubs I simply ground the rivets flush with the trunnion and rear tang, marked center of the rivets and drilled holes for the drive screws. I determined the size hole I drilled by measuring the small end of the drive screw and using the appropriate size drill. I believe the drive screws I used were a #10, but I don't remember the size hole I drilled. For the rear tang I used the drive screws full length, but for the trunnion I ground them off to about .240" because the holes I drilled were only .244" and the drive screws were .250". I then put my parts into my receiver and used my hydraulic press to set the drive screws. The reason I used my press was that I was afraid that I might start one crooked or wreck something swinging a hammer, although I am sure you could use a hammer if you were careful. I could only use 4 of these on the trunnion because after I ground the 2 rearmost rivets flush I pushed the rivets out and my drive screws weren't big enough to use on the holes left so I used some grade 8 10-32 screws I had left over. For the center support I used my usual length of 1/4" stainless tubing and drove a drive screw into each side to hold it in place. For the trigger guard I used nuts and bolts. __________________ A village in Massachusetts got their idiot back.

01-06-2006, 03:41 AM	#11
d.hauser Member AKaholic #: 5060 Join Date: Dec 2005 Posts: 98	drive screws ok once i actually get my kits, they should be here next week. i will figure out just what size we would need. i will then get the drive screws and figure out how much it would actually cost for a set. then if any one wants i`ll give my address and you guys can send me the actual amount, plus for the padded envelope and shipping. i have a press but i was thinking on making a concave type of drive punch and just use a hammer to set them. __________________ NUMBER ONE WITH A BULLET

01-02-2006, 01:42 PM	#1
Thanatos Member AKaholic #: 2620 Join Date: Aug 2004 Location: Omro, WI Posts: 126	Easiest AK build EVER. A couple of months ago I did my easiest build ever. Over on gunco.net we used to talk about using "type U drive screws" to do a build, but no one ever got around to doing one that I know of. Well a couple of months ago I got access to about a dozen of the drive screws and I had a kit at home unbuilt so I said "what the hell" and went to work. All it involved was grinding the rivets flush and drilling the appropriate size holes then pressing the drive screws into the holes. No headspacing, pulling of the barrel or removing the rivets. I used the drive screws for 4 of the trunnion holes, the center support, and the rear tang. I did end up using screws for the 2 rearmost trunnion holes because I removed the rivets and the holes were too big for the drive screws I had, but I am sure I could have used drive screws if I had bigger ones. Yesterday I finally got the opportunity to test fire the build and it ran like a clock. I fired about 300 rounds through the rifle with no adverse effects on the drive screws. This would be the ideal build for guys with limited tools. __________________ A village in Massachusetts got their idiot back.

01-02-2006, 02:34 PM	#2
fraxxian Member AKaholic #: 3845 Join Date: May 2005 Posts: 335	so are these some sort of self tapping screw?

01-02-2006, 06:02 PM	#6
jwolf74 Member AKaholic #: 4590 Join Date: Oct 2005 Location: S.E. Pennsylvania Posts: 27	Anyone having more info on this type of build please share with us. What size you used , etc....

01-02-2006, 08:21 PM	#7
mj2evans Member AKaholic #: 4121 Join Date: Jul 2005 Posts: 25	Do you hammer these in or pressed like a regular rivit? Could you use this in tjhe front trunion without removing the barrel?

01-05-2006, 03:27 AM	#9
d.hauser Member AKaholic #: 5060 Join Date: Dec 2005 Posts: 98	drive screws i deal with mcmaster-carr alot at work, so i checked out the drive screws. they come in bags of 100 if i under stood the description right, and they are cheap. i have three kits to build and i now plan on using this method of assembly. but i wont need all of the drive screws. so if you guys are interested maybe you could send me a self addressed padded envelope and like a buck...lol, and i will send you the drives screws you would need. i need to figure out the correct sizes. they have steel and stainless ones. let me know.................. __________________ NUMBER ONE WITH A BULLET

01-05-2006, 06:54 AM	#10
spraynpray Member AKaholic #: 4634 Join Date: Oct 2005 Location: Great Smoky Mountains Posts: 89	Very impressive, I imagine that along with everyone else we would be inteered in a "kit" of these that would press into the trunion holes. I already have a couple of kits with the rivets removed and so they would need to go directly into the trunnions. The look and hold of rivets without all of the hassle.

01-06-2006, 09:21 AM	#12
spraynpray Member AKaholic #: 4634 Join Date: Oct 2005 Location: Great Smoky Mountains Posts: 89	It might be interesting to see if one of the bolt cutter rivet crunchers would drive them in. The punch idea seems very logical.

01-06-2006, 02:48 PM	#14
lpspinner Member AKaholic #: 4329 Join Date: Aug 2005 Location: CO. Posts: 28	Would you/Could you add some Red Loctite? Do the have a larger size for the rear that would fit the existing hole left over when the rivet falls out?

01-06-2006, 11:46 PM	#15
mj2evans Member AKaholic #: 4121 Join Date: Jul 2005 Posts: 25	d. hauser - I would throw in a buck or two for a couple of screws to play around with.

01-07-2006, 12:01 AM	#16
Tilton Hilton Member AKaholic #: 4685 Join Date: Oct 2005 Location: SW PA., USA Posts: 53	I'm also very interested in hearing anything additional regarding this method. Jim

01-07-2006, 05:24 PM	#19
tanlover442 Member AKaholic #: 4557 Join Date: Oct 2005 Location: TEXAS...by God! Posts: 431	wow... ....now this is one heck of an idea!!! this selfsetting rivit idea would be fantastic!!! lets hear from someone who has built one and had it working for awhile.

01-08-2006, 02:43 AM	#20
cntrailrider Senior Member Contributor AKaholic #: 3152 Join Date: Nov 2004 Location: EL Paso TX in the desert / NFA Country Posts: 818	I like this idea. You have my attention - Steve in El Paso

01-08-2006, 09:30 AM	#21
Wrangler New Member AKaholic #: 4597 Join Date: Oct 2005 Posts: 8	U drive Hi, I just ordered some 8s and 10s from Mcmasters. Should have them this next week. It would be interesting to try them.

01-08-2006, 09:32 AM	#22
Wrangler New Member AKaholic #: 4597 Join Date: Oct 2005 Posts: 8	EPT Just for the record I am another West Texan (native).

01-08-2006, 11:01 AM	#23
tanlover442 Member AKaholic #: 4557 Join Date: Oct 2005 Location: TEXAS...by God! Posts: 431	Wrangler..........howdy pardner tanlover442

01-08-2006, 01:29 PM	#24
cntrailrider Senior Member Contributor AKaholic #: 3152 Join Date: Nov 2004 Location: EL Paso TX in the desert / NFA Country Posts: 818	Wrangler - email me direct cntrailriderNOSPAM@msn.com I cannot send PM's on here anymore for some reason. Steve

01-08-2006, 08:45 PM	#25
xuanloc69 Member AKaholic #: 5137 Join Date: Jan 2006 Posts: 43	Screws I'd like to try it. Can you send me enough for 2 builds?. How much & where to? Thanks.

01-09-2006, 12:20 AM	#26
Mandaree36 2nd Class Member Platinum Contributor AKaholic #: 4562 Join Date: Oct 2005 Location: North Dakota Posts: 14,470	Wow this thread is growing. I am in too. PM with your contact info - I want to try these as well. Damn and I just got my rivet kits...oh well I guess I will have to build more of each...you know for evaluation purposes.... __________________ CENSORED.. I wont check my religious beliefs at the door....to accomodate you - nor will I apologize for them... We do not ask for your poor or your hungry. We do not want your sick and tired. It is your corrupt we claim. It is your evil that will be sought by us. With every breath we shall hunt them down. Each day we will spill their blood. ‘Till it rains down from the skies приедьте и получите некоторых Вы трусы

01-09-2006, 10:24 AM	#27
Bruce R. Member AKaholic #: 2020 Join Date: Apr 2004 Location: DC area Posts: 200	I hope you realize that these pins are for location, and don't supply any reliable clamping force. If and when they back off, even a little, you lose all the integrity of the joint. Hammering them back will not help because you will have lost the fins on the shank of the pin, and that's what holds these things in place. Both rivets and screws work because they are under tension and act like springs to an extent, you don't get that action with a drive pin. I think you are making a mistake by trying these pins, and I hope you don't get hurt when they start to loosen up.......

01-09-2006, 10:31 AM	#28
robdog Senior Member AKaholic #: 5069 Join Date: Dec 2005 Location: NC Posts: 884	I agree with Bruce, There is a reason that rivets are still used to this day for building AK's. Superior holding power. If it aint broke dont fix it. Stay with the tried and true method that has worked for 50+ years.

01-09-2006, 12:15 PM	#29
lpspinner Member AKaholic #: 4329 Join Date: Aug 2005 Location: CO. Posts: 28	Back to my original question... What if you use the drive screws with Red Loctite? Wouldn't that help?

01-11-2006, 05:47 AM	#32
VaFisher Member AKaholic #: 5065 Join Date: Dec 2005 Posts: 36	Bump

01-11-2006, 05:59 AM	#33
Bruce R. Member AKaholic #: 2020 Join Date: Apr 2004 Location: DC area Posts: 200	This may come across as insulting, it is not meant to be in any way, shape, or form. These drive pins are used for things like attaching name plates to motors and equipment. You have seen them used that way I'm sure. They are probably what's holding the data plate on many of the hydraulic presses we use. How many times have you seen a loose name plate on a piece of equipment or a motor? In order to provide clamping force you have to stretch the bolt, screw, or rivet by some method. These drive screws can't be stretched because they are hammered in from one side. In point of fact, they get compressed when hit, and then spring back just about guaranteeing that they will not be tight. No matter how tight you think you have them, all it takes is a few shock loads and there will be movement, and there is no way that you can re-tighten, even if you try to hammer the pin back in. All that will happen is that you will wear away the "fins" that are providing the friction that holds the pin in place. These drive screws are NEVER used in critical installations because they can't be relied on to hold anything together tightly. I have been looking through all of the major suppliers catalogs for some data to back up what I have stated, but so far I can't even find a manufacturer of the pins. However everything I have found is limited to name plate attachment and light duty fastening where an ALUMINUM pop rivet will do the same job. It's certainly not my place to tell anyone what they can or can't do, after all it's their rifle, and their head and eyes, but I think that a bit more research is called for before we jump to the conclusion that any fastener will work to build an AK. If that were the case we could use ordinary hardware store screws, or even aluminum rivets to hold these things together. I would respectfully ask if anyone here has ever seen these fasteners used on any centerfire firearm, ever,….. I know I haven't, and if they are useful and will work, particularly in a stress location, don't you think some one, some where, would have used them? "Would seem to me that the only significant load on the rivets in an AK (at least front and rear trunion) when shooting, are shear loads normal to the axis of the barrel, not tension or compressive loads which would perpendicular to the axis of the barrel." That's not entirely accurate. If you saw the very slo-mo photo's of the AK being fired on the History Channel a while back, you might have noticed that the receiver bounced and flexed as if it were made of rubber. There are forces going in all kinds of directions. I once thought as you do until I saw that film, the loads were clearly not only in shear. You might also have noticed that some of the rivet holes are counter sunk into the trunion. When the rivets are pressed in place, they force the sheet metal of the receiver into that countersink adding significantly to the shear strength of the joint, while not transferring that load to the rivet, instead a tension load is applied because of the sloped angle of the two pieces.

01-12-2006, 08:06 AM	#34
Thanatos Member AKaholic #: 2620 Join Date: Aug 2004 Location: Omro, WI Posts: 126	Bruce, thanks for the pearls of wisdom, but I know for a fact that there are drive screw builds out there with cases of ammo through them with no failures. I also have a slow motion video of an AK firing full auto with the dust cover removed and I can't say that I notices any "rubber-like" tendencies associated with the receiver. While I appreciate your commentary, I am very confident that this is a very feasible option for the home builder. Although I believe this is a great idea that I wanted to share with the community, if you have ANY doubts about the integrity of these fasteners, please DO NOT build this way. And if you do build this way, do like I do with every firearm I shoot: Always be looking for any type of abnormality with the firearm, and inspect it at regular intervals. With my drive screw build I checked it after every few rounds when I first shot it, now I check it less often. Here is a link to the slow motion firing of the AK. I don't see any of the dramatic flexing that you talk about. Full auto AK in slow motion. __________________ A village in Massachusetts got their idiot back.

01-12-2006, 04:18 PM	#35
Bruce R. Member AKaholic #: 2020 Join Date: Apr 2004 Location: DC area Posts: 200	As I said before, these are your rifles, and you can build them any way you want to. I have reviewed once again the History Channel footage, and the flexing of the receiver is obvious. For what ever reason I can't seem to pull up the web site you mentioned, so I can't comment on it. I also went to the web site mentioned in Bubbajj's post: http://www.sksboards.com/forum/view...p?p=94952#94952 There is some obvious mis information there. The type U drive screw is shown in doneking's post to be deformed after being driven into a hole. That seems to me to be unlikely because the screw is supposed to be hardened to the point that the fins bite into the base metal of the bored hole. It's highly unlikely that you can have it both ways, that is hard enough to bite into a hardened trunnion and soft enough to deform when it strikes the barrel. Again, all I can say is that I have never seen these "screws" used in any high stress location, and I certainly will not take the chance of finding out. Best of luck with your build, and I promise I'll say I was wrong, and you were right when you put 10,000 rounds through your gun without a failure as they routinely do with rivet and screw builds.

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