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View Full Version : AK top rail idea... what do you think?


jason41987
August 25, 2012, 04:53 PM
hey everyone.. this will sound cliche, but i came up with this idea in my sleep... happens a lot to me for some reason.. but here it is

i notice people coming out with top rail solutions either offer a fixed rail above the top cover so the top cover can still be removed, or some hinged mechanism so the rail can be attached to the top cover... well, my idea requires a bit more work.. but i really like this idea

so.. for this idea, the rear sight block is machined flat on top, and on the top of the rear sight block, a top rail is mounted extended all the way to just in front and above the rear trunnion... and it just hangs there (i may support it on the left side with a piece that shares rivets with the rear trunnion, but ignore this for now

anyway.. this rail rests directly on top of the top cover... why this doesnt matter is im ignoring the traditional means to remove this top cover.. and instead the bottom of the rail that hangs over the cover will be dovetailed on the bottom so that the top cover can be slid over the dovetail from the rear of the rifle...

the rear trunnion will be a little taller, and contain a rail for the top cover to slide into as well.. so the top covers slid over both the rail on top, as well as over a groove in the rear trunnion, bridging and supporting the top rail to the rifle... to lock the top cover in place i havent decided what method would be used... a pin, perhaps a lever, but the idea id like to try out is using a couple ball detents to not lock the top cover on, but to add retention so itll stay secure and not come lose, but require a tug on the back side to pull it off and expose the internals of the rifle for field stripping

this rail could be extended forward too... a new gas block could be machined that would support the front end of this rail so you will have a straight, uninterrupted rail stretching from the very rear of the top cover to the top of the gas block

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so.. what do you guys think of this idea of adding a fixed full length top rail to an AK that would maintain a perfect zero at all times, allowing red dots, magnifiers, scopes, and NVG devices to be mounted anywhere you choose?

Crow Hunter
August 25, 2012, 06:06 PM
How will you get the bolt carrier/piston out?

If your rail is touching the rear trunnion and is mounted where the rear sight is today you won't be able to get it out. ;)

5.56RifleGuy
August 25, 2012, 06:12 PM
I had the same thought. Good thing you never need to clean them or replace any parts. :)

jason41987
August 25, 2012, 06:13 PM
the rail would be supported in the rear while the top cover is in place.. the top cover would lock between the rail and the trunnion.. with that removed itll be open straight through and on both sides...

however... to prevent damage to the rail with the top cover off, ive considered having a piece riveted to the left side that would act as a leg for the rear of the rail when the top covers off... this would only be on the left side though so itll can be lifted up and out through the right side

im trying to debate if i should have this one-sided leg on the back rear of the receiver to further support it or not... this "leg" would probably share the rivets with the rear trunnion.. or in this case the left side of the trunnion would be tapped for screws

Crow Hunter
August 25, 2012, 06:29 PM
I am still not seeing it.

If you have a rail that is mounted to the front trunnion that extends all the way to the rear trunnion. How do you get the bolt carrier out? Are you taking the rail on and off the front trunnion?

jason41987
August 25, 2012, 06:44 PM
crow.. the rail is just a narrow piece of metal with cuts in it to mount optics... with the top cover off the rail would just hang there above the receiver and the top cover is installed by sliding it onto the receiver between the receiver and the suspended rail from the back side of the rifle

5.56RifleGuy
August 25, 2012, 06:48 PM
Yes, but to get the bolt carrier out, you have to slide it back and lift out of the receiver. It doesn't seem like you would have enough clearance to get it out, and it would be a pain to get back in.

jason41987
August 25, 2012, 06:55 PM
you dont have to lift the bolt out that far...some side mounts on the market for AKs have just barely enough clearance to get the top cover off and still dont have problems pulling the bolt out.. so i dont think it would be a problem.. if it was you could just raise the height of the rail on the order of millimeters to make clearance

5.56RifleGuy
August 25, 2012, 07:11 PM
Don't most of the side mounts have a quick detach? Can they be disassembled with the mount in place?

jason41987
August 25, 2012, 07:13 PM
yeah, most the AKs with attached side mounts can be stripped without removing it.. unless the mount is directly on top of the cover.. why?

5.56RifleGuy
August 25, 2012, 07:17 PM
I didn't know so I asked.

Crow Hunter
August 25, 2012, 07:40 PM
I think it could be done, but you will still have the crappy chin weld that you do with most Commbloc optics and all the parallax issues that results in, unless you build up the stock to compensate, then you can't get the bolt out. Again.:D

jason41987
August 25, 2012, 07:49 PM
i should make a concept AK using this top rail system and improved ergonomics (extended mag release for drop free magazine, left side safety lever, and perhaps a tool-less barrel change)

5.56RifleGuy
August 25, 2012, 07:51 PM
You have to be careful with making an extended mag release. Some surplus mags have a steel spine on the back that will get in the way and prevent the mag from releasing. Pretty annoying to try and correct.

jason41987
August 25, 2012, 07:56 PM
not to get off topic... but im thinking of machining a new trunnion where its railed on top to support the dust cover and gas tube so i can eliminate the the rear sight block and make the rifle entirely free floated.. then mount the rail to the gas block, have it slide into a dovetail on top of the trunnion, across the top cover and secured by the dust cover to the rear...

reason for this would be i would machine the locking lugs out of the rifle, and build a barrel-extension to fit the receiver-end of the barrel thatll contain the locking lugs so i can slide this along with the gas system and rail system onto the rifle, secure with a lever or detent-locked thumb screw / castle nut to hold the barrel in, and since this top rail system could be made as part of this system it would maintain zero when the barrels removed

MagnumWill
August 25, 2012, 07:57 PM
I see what you're saying - and I dig it! That would be ├╝ber cool to modify that dust cover so it just slides right off the back. And I think that you coul make it just high enough to get the piston out without it interfering- I think a lot of people are under the assumption that the piston is practically touching that cover. I think if the sight rail you make is only about 3/8" higher than the (current) dust cover, you'd have room for said dust cover and dovetail.

...and here's another thing- if you're planning on making a new dust cover that has the locking dovetail, then you COULD properly mount stuff on it as well, since it's now pretty solid with the sight base. ACOG on top, CQ red dot sight on the side at 90 degrees? Fricken' count me in man. Good thinking :thumbsup:

Crow Hunter
August 25, 2012, 07:58 PM
Like this?:D

http://www.m4carbine.net/showthread.php?t=97688

MagnumWill
August 25, 2012, 08:08 PM
Just did a quick look on the Internet, and I like this idea. I've found that people who make scope mounts go through a great ordeal to build a scope system that works around that crappy, crappy piece of metal that is the dust cover. I would rather make a good scope mount that doubles as a dust cover, and not the other way around... :)


And Crow, it looks like that one's hinged up at the rear sight base as well. If you were to redesign the dust cover shape, why not covert it to a left-side charging piston while you're at it?

jason41987
August 25, 2012, 08:20 PM
see now.. that AK-12 hinges the top cover.. theres a break in the rails and its not going to hold a perfect zero as long as a fixed top rail would

im not sure id use a lever to lock the dust cover though.. it would be the most AK-esque way to do it.. but im really liking the ideas of adding retention with ball detends so you could just yank it off.. a lever with a cammed shaft would work too though

could you imagine this rail system though... if i was able to get a free-floated quick change barrel on there for easy caliber conversions....

of course.. with a full length top rail there would be little need for that barrel mounted front sight

i really need to start working on specifics in 3D, then i can render the receiver and the carrier with the rail installed and see if there are any clearance issues, and if there are i can adjust them in 3D before ever spending a dime on a prototype

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ive seen AKs that were left side chargers.. had to remove the old bolt handle and drill the opposite side of the receiver for a new one... bolt handle could be easily moved to one side or the other

i think the AK could benefit from a left side charger more than an AR could.. since it doesnt have a bolt hold open feature and youre required to rack it everytime you change a magazine... ive seen aftermarket hold open modifications, but no true bolt hopen with a bolt release

5.56RifleGuy
August 25, 2012, 08:29 PM
The ak 12 can be converted to a left side charging handle and features a bolt hold open.

jason41987
August 25, 2012, 08:33 PM
id love to see the specs on their bolt hold open feature.. if it works on that it can easily be adapted to an AKM

izhmash is actually working on civilian-legal AK12 prototypes, most likely to be sold in the american market now that russians a WTO organization theyll most likely be exporting a lot of their guns here soon... AK12 as well as standard AK-47/74 and quite possibly their AN-94 could quite possibly be purchasable by us in the near future... and brand new rifles too, not this "assembled from a box of used parts" crap

Rampant_Colt
August 25, 2012, 09:25 PM
Sounds like a version of the Polish Beryl piccy (http://www.robertrtg.com/berylrail.html)

http://i47.tinypic.com/54br83.jpg

MagnumWill
August 26, 2012, 02:25 PM
Nope, that's ALSO a hinge mount. Think if you could, it was a solid piece attached to the front trunnion. Again, had to make a very expensive bracket so you could keep the same crappy bent sheet-metal dust cover :rolleyes:

1BIGGUN
September 2, 2012, 04:11 PM
LOL i have been making a canter leaver type sope mount on aks for over 6 years. its not very hard . mill the top of you RSB off an then weld in a steel rail. I mill my own rails with a chanel on the under side to get it even lower to the dust cover. you can also w make one that attaches tot he side of the RSB if you dont want to mill the top off.

my 223 varmint Build uses one an it shoots under 1/2" lots of pics of it on GUNO. gettting the mount away from the reciver is key the reciver has flex. if the mount touches it or the rear trunion or any hting its not going to be as good as my set up.

a couble pics of one of them

1BIGGUN
September 2, 2012, 04:24 PM
here is a pic of one i did on my sons hunting build to hold a 3x9 leuopld scope. the welds were not cleaned up in the picture but the scope is very low an the cover will come off. use a smooth cover to get it lower an id advise adding some side support on the LH side this perticular nount will likely bend if it was dropped. It holds zero an the gun shoots pretty good ;)

shot the goup with Lapua brass an 110 gain vmax in a .310 dia

jason41987
September 3, 2012, 12:16 AM
now if only you could make it low enough to touch the top cover.. and extend it all the way back.. perhaps support it with a piece that shares rivets with the rear trunnion... then make a top cover that slide in and out from the back and youll have what im describing.... like how a FAL cover is attached