Homemade AR-7 type rifle

[A-BOMB]

Well Its been awhile since I've posted anything about the guns I make, and this gun is going to be a good one so heres some specifics about it. I'm still waiting for some of the parts. Well I'm going to buy the barrel/s from HERE (http://www.e-gunparts.com/featureproduct.asp?chrProductSKU=878300&Super=N&MC=YJ) Numrich has more gun parts than God. And if you ask why about the rusty barrels it because I'm cheap and 5 for $19 you cant beat that.
And I'll be buying the metal tubes for the receiver/barrel block/bolt from here www.onlinemetals.com. I'll post my diagram in a minute right now I have to get some stuff out of the drier before it rinkes.

[knowledgehungry]

Very nice site, thanks for posting it. What type of action is your gun going to be? bolt action? semi auto? full auto:D ? Sorry but im not familiar with AR7's.

[A-BOMB]

Its going to be a semi-auto in .22lr caliber but its to hard to explain right now I need to scan in my diagrams I'll get around to posting them later, it depents if I can finish this damn VB course work.

Here is a picture of the parts I have currently aquired they are ontop of some of my schematics for the gun I'll scan them or take pictures of them soon.

HERE (ftp://ewf:sd332gf@209.195.155.80/Hosted%20Images/A-BOMB/Pcdv00054.JPG)

[zaibatsu]

Is it going to be blowback? Open or closed bolt? Are you making it so that you can dissemble/stow it away in the stock like the AR7? AR7s look like fun rifles, I think you can also buy them over here.

[A-BOMB]

Its going to be a closed bolt, blowback, semi-auto, Its going to be AR-7 like but will not be able to be disassabled its going to have a strong center pin on which the action and barrel will fold on like a door hinge. I pull out the bolt that hold it in place and fold it back into a slot cut in the stock. I'm thinking of useing a mak-90 or AK thumb hole stock because there big and look cool and real cheap like $16. And ya I could buy a AR-7 at a gun show or from there website but they offen have big problems, metal shaving left in the chamber, bent parts, screw holes stripped, massive feed problems. I'm not saying that mine wont have these at first but in mine I'll have know I've built it myself, and it I'll be cheaper too.

[Charlie Workman]

Sounds cool A-bomb. Love to see it when you're done. Personally, I hate the AR-7. Owned both the pistol and rifle versions and neither were reliable for shit. Most people I talked to really like them, so maybe I got the bad ones. Had a manual on full-auto conversion for it, which I always thought was a giggle, since I could never get them to fire more than two rounds on semi before they jammed.

"To paraphrase Aristotle, life is a gas!"
-Gidget

[A-BOMB]

I just ordered the barrel, stock, receiver tube, bolt metal, springs, and other part that I didn't have. Since the barrels I was going to order is out of stock I have to order this one HERE (http://www.e-gunparts.com/product.asp?chrProductSKU=586860). But the rest of the parts were in. Here is the metals I am going to use the .75"(ID) tube if for the rifle and the .875"(ID) is for the SMG version which will need a heavier bolt to contain the recoil of the shorter length bolt that is needed in the SMG version. The SMG version is going to be P-90'ish that it is going to be a bullpup unit with the mag over the barrel. Its even going to have bullets that are similar, .125" TI rod in a 5.45mm semi- dicarding teflon sabot.
I should have the parts by Saturday or Sunday Monday the latest. But first I have to find a .375"(3/8") metal drill and get a new belt for my drill press.

https://www.onlinemetals.com/check_order_status.cfm?id=49500&step=2

[A-BOMB]

Well I got the barrel and stock to day, and all I can say about the barrel is I HATE cosloimine grease it is the anti-christ lord of no come-offyness and stickyness it doesn't want to come off! I used a couple of quarts of kerosen taking that shit off. And the stock has some dinks and nicks, and I'm happy with the files I got too, thought I did forget some things one the order, I'll get the sight rail/scope rings later.

Here is a pic of the blue print because my scanner just bit the dust (I cracked the glass plate) perminatly so heres a pic.

[angelo]

A-BOMB have you ever used shellite. Its more expensive than kerosene but it does the job alot better.

[Arkangel]

I've not found any lubricant that acetone won't dissolve in a jiffy

[A-BOMB]

Angelo, do you think this 'Shellite' it avalible in the US? And if it were, where do you think I would be able to find it,?

Well I got $18 dollars left on my prepayed credit card to use up any ideas, I borrowed the drill bits I'll need and the locking pins and cutoff wheels for my dremel tool. Oh that reminds me I bought every thing with one of those new prepayed credit cards I got a CVS I think this thing is great you pay a $9 dollar one time fee and then can put any amount from 20 to 500 on it. To recharge you just buy a recharge card for $4 and then put more money on it. Though you do have to call in and give them information on were to send the card with you name/exp date/pin.

So anybody have any idea on what I could buy with it item+ shipping for $18 ?

[GibboNet]

Shellite is a spirit like metho, used for old style camping stoves. You'll find it at most camping / hardware stores.

Also, would you mind explaining the pre-paid credit card ?

[A-BOMB]

Sure, I was a CVS( a chain drugstore over here in the US) picking up some candy and cold-packs, while I was at the counter getting rung up I saw the prepaid credit card. So I bought one it has a $9.95 activation fee then I could put as much money on it as I wanted($20-$500) so I bought it for $90 dollars gave the man at the counter his money and he activated the card and it temporary pin. I got home and opened up the papers that came with it I went to the website and read/accepted the end user aggrement. Entered in my information address,phone,birthday etc etc etc. Then I called the number on the form, gave them the info again and then they gave me the new real pin number, exp date, and security number and then they asked me if I wanted to upgrade etc etc etc and other shit, then said I'd get the real card with the data on it in 7 to 10 days and that I could use that temporary card online till the real card comes, that will allow me to use it in a real store(the temp card has a one time use magnetic strip).

It was a bit of a hassle but hell its easies than sending a check, to recharge the card you just buy a recharge card for $4 and then add more money to the account, and there is a $4 monthly service charge but aleast I'm not paying intrest anymore+ the monthly charge so I works for me for how little I use it.

check out www.mymccard.com to see more

[angelo]

Well I know shell produces it. I do believe its proper name is x-55 petroleum spirit. But I'd have to check for you. We recently bought a 200 litre drum of it at work.

I don't think acetone would be very safe. Sure it will dissolve anything, but that includes your hands. Be careful Arkangel.

[A-BOMB]

The metal tube for the reciever was suppost to come today but the the UPS guy got lost and called me for directions, he said that me address must not exist because he could not find it. Then he reads me the address and its the right address and I tell him its right, and he said I was wrong about that. Then I tell him if my address doesn't exist then how am I on the phone with you from it now. Then he asks me for directions, so he can deliver it the next day because his shift is over. :mad: I'm thinking of killing him and taking his truck tommarrow, I wonder how much goodies would be inside?

[chemwarrior]

Hehe, A-Bomb.. killing him might be a little extreme... but tying him up and leaving him in the woods.....

Also, I have one of those pre-paid credit cards too.. They work wonders when your under 18:)

[A-BOMB]

The metal Tubes just came! Let the production begin! But there is one thing wrong with my order when I talked to the guy from the store I he told me the tube would be seamless, well its welded seam tube I will just take me some time to grind it out with a file. I should be able to start it this evening right now I got to sleep, I've been up for the last 23 hours clearing the water and shit (real shit) out this house I was rentovating the main sewage line broke,up in a wall on the second floor and it ran down throught the walls down into the basement.

[A-BOMB]

I just cut the 12 gauge plate steel for the lower receiver and bent in the flanges for welding, have ground the seams out of the pipe and have started adding metal to the outside of the barrel with my MIG, as the barrel is sightly less than .75" on the outside so I have to add more metal then grind it away to make it fit in perfectly. I should have the bolt started soon and the extractors, firing pin, and sear finished soon too.

[A-BOMB]

I haven't updated my progress in a long while so here it goes I have finish milling out the trigger group and drilled the respective holes in the lower and have finished the bolt and have gotten it hand cycling shell semi-reliably just need final polishing. Soon I will have to take all the parts over my budies metal shop to have them heat treated, harden and blued then comes fire testing.

[NickSG]

Cant wait to hear the results. Make sure to get some good pictures too! :)

[A-BOMB]

Well here is a update I have to make a new trigger group and alot of other stuff now, I got it out to the range and terror strikes, I load a shell up and it fires so far so good, I load up 2 shell and they fire once with each pull of the string then I load up the whole clip of 21 this is when the bad happens, It seems that the sear slowly falls down after holding the striker for awhile, I get up and go over to the bench were I got the gun bolted to and I look through my spotting scope at the target to see were I hit it and the gun just goes full auto on me. One of the shells mis-chambers and fires in the action blowing out the rear receiver plug, springs, striker and bolt out the rear of the receiver into me as I'm over the gun looking through the scope. Well the damage is bad I need to cut off the chamber section of the barrel and rechamber it. Grind out the gouges out of the face and sides of the bolt, grind out the cuts out of the receiver then I'll need to see if I need to make a new receiver or if this one can be salvaged. And redesign the trigger group and make a new set and harden them. So after this I find the internals and servey the damage and packup everything to get home as I'm driving home I see this estate sale so I stop by, and god I wish I got there earlier, I mean this guy would have be a perfect member, he had so much stuff guns, paintball markers, rockets, RC cars/planes/boats, a big lab room with every thing we would ever want electronics, chem equipment, metal working equipment, and a shit load of military surplus. I wish I could of bought it all. I wish I could of bought the entire house! But there is never enough money when you need it :mad: I only was able to get this box with all this paintball stuff and a bunch of electronic and a military gear harness set kind of think and a bunch of D rocket motors. But I may be able to use some of the paintball gun stuff especialy this E-trigger that what is the box. If I can get it to work and fit I will have a semi,3rd burst, and full-auto functions.

[Jacks Complete]

Oh, shit!

Lucky for you you hadn't gone forward to change the target!

Did you get hit by anything?

[A-BOMB]

I got a finger nail torn off and some metal fragments from the case in my right hand right now so I'm typing lefty, I'll dig out my surgical kit later and dig them out some time right now it just give me an excuse to not be at work. The most damage was to the rifle I'll heal quicker than the rifle will.

[xyz]

Very sorry to hear that A-BOMB, looking forward to seeing the AR-7 whenever you eventually get round to finishing it.

Next time a newbie posts a stupid thread about how they want to make a homemade firearm, give them the link to this post so that they can see what .22LR can do to an experienced member.

That should make them think twice about wanting to make a .308 or a .50BMG...

[A-BOMB]

Well I thought about it and I'm going to rebuild the rifle into a bullpup design like in this drawing, I have looked at the e-trigger and it is lacking in sear strength so it is out but one of the other triggers will work so i'll use that. the lower drawing is was the gun looked like before the upper one is what the gun will look like after I'm done rebuilding.

[Jacks Complete]

A-BOMB,

are you going to list the notations? It would help! :)

Nice idea.

[A-BOMB]

Sorry about that forgot

A: Barrel
B: Trigger/trigger guard
C: Stock
D: Clip
E: Clip relese
F: Stock again
G: Buttplate relese
H: trigger group
I: Buttplate
J: Receiver/recoil and firing pin springs
K: Firing pin/extractor
L: Bolt

I got the idea for remaking it a bullpup from the fact that the stock is now gouged out were the receiver was before I would looke neater as a bullpup, So I'm going to put the stock on my bandsaw and cut it in two then I will hollow out the sections of each side to acommindate the receiver and mechinisms

[Ammonal]

Just throwing ideas around A-BOMB, I am working on Bill Holmes .22 Machine pistol at the moment and I have had to improvise a couple of things because I lack a mill. I like your idea of converting to bullpup, but I have one concern with bullpup firearms (yes I have experience with the Steyr AUG, and the only thing besides that the weapon is made out of plastic) is that the action is right beside your face. Because of this I am making double of each part for the machine pistol in the hope that once I get the standard layout working well, I would like to try a bullpup version. The only difference is that I have made all of the upper reciever alot heavier (3mm wall DOM seamless) and the endcap is 12mm thick with a 6mm pin holding it into the end of the upper reciever.
Earlier in this thread you spoke about making a P90'ish model, and as I am lacking in high capacity magazines and they are extremely difficult to come by, I was wondering if you had any information or diagrams of the magazine system used in the P90

[A-BOMB]

The P-90 uses a horizontal double stack maginzine with a rotating section on the rear to line the bullets up with the barrel. The P-90ish unit is on the shelf for right now(to much stuff to do) but the clip I made was just a of rectangular tube that the case of the shell (minus case rim) fit into then another tube that the first could fit in, I cut the rear off of the tubes so they could fit inside each other then I spaced them apart so the rim of the .22 fit then I drilled and put in the pin in the end so It folds open for loading after the spring follower is pulled back and locked, (look at the drawing. One thing you see is the curved part on the end of the clip that part turns the shell to be inline with the barrel. But there is one thing that I couldn't draw effectively and that is the spring steel ends on the clip they keep the shells out of the turning section of the clip till it is inserted into the weapon there two metal rod push back the springs and allow the shells into the turning section and the weapn.

A: pin
B: Spring
C: Spring Follower

[Ammonal]

Thanks A-BOMB that looks so much easier than trying to backwards engineer a picture of a P90 magazine! I have a day off so I'll try making one today (i have a pile of RHS tubing which should be handy). One other thing what do you use for your magazine springs, do you use the normal music wire DIY springs or have you got another method for them? I have just had the suggestion made to me by a good friend of mine to use clock spring that is the flat strips of spring steel and fold them into a long ?/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\| 'W' spring. I tried this and it worked extremely well in a 15 round .22 magazine. You just get your clock spring, heat it and let it cool, fold into shape (some smooth mouth pliers work well) and the retemper it by heating it to cherry red and dunking in oil, then sand a small section til it is shiny and reheat the spring to the straw colour and dunk it in oil again and it is ready for use. I have covered some old ground there about the tempering, but the information on the spring was just worth sharing.

[A-BOMB]

I went out to my local DIY store and got some long springs ment as replacement for the long springs in the clips on a staple gun. If you got the time and equipment you can make a helical mag by taking to pieces of round tube one smaller than the other and cutting a sloped spiral slot into it (list a screw) and then cutting a piece of sheet metal into a spiral that can fit around the smaller pipe to line up with the slot then mig weld it in place. Then mill out a block that has a curve on the bottom to match the angle of the sheet steel now take a piece of round rod stock that fits inside of the smaller pipe and drill and tap a hole in it to fit a bolt inbetween the curved block and the round block insided the smaller pipe, now take a long strongish spring and put in inside of the smaller pipe so it pushes the blocks up along the spiral shell ramp. Now put the whole asembly into the larger pipe and seal off the one end with a end cap or something else that is removeable. Now is a much harder part you got to make the end shell ramp by cutting and welding together sheet steel, this is one alot harder then what I have now so I scrapped this idea, but if you want you could try it and see how it goes.

[DimmuJesus]

By the time you have this finished, how much do you think it will have cost you total to build? This sounds like it may turn out to be quite a gun! If this works out, are you considering using a similar design for larger calibers? With the select-fire function, what do you anticipate the rate of fire being? And one final question, will this only take mags made for the AR-7?

[Jacks Complete]

A-BOMB,
I think you got B & C reversed on the mag diagram.

How does the P-90 magazine feed the last round? It doesn't seem like it would work with the follower you have drawn, as there are no more rounds to push it beyond the mouth of the stack. Do you get rounds falling out when you take off a full mag? How do the two pins re-engage?

[A-BOMB]

I didn't notice that simstake before, Well the mag in the drawing is for my smg that I was making but right now the smg is shelfed, Now on to the clip the pins have sheet steel springs on them to put the pins back in place. I never finished the smg but right now, when you load a mag 3 rounds are inside the receiver(2 in the mag well and one in chamber) to keep mag in place the are 2 ball bearing locks they are in the chamber just enough to hold the 3 shell in and gravity draws them into them chamber. So if I put a full mag of 28 rounds in and i remove it without firing I will have 25 round left in the clip.

[U.S.M.C-Man]

This might help you with this (see link below). I think a scratch-built AR 7 scaled up to 9mm would be awsome.

http://www.roderuscustom.tzo.com/cgi-bin/ib3/ikonboard.cgi?s=404b5fa503f0ffff;act=ST;f=23;t=92 .

- U.S.M.C-Man

[A-BOMB]

As of now my AR-7 prototype is dead, I'll be working on a new model soon but my first is just a lost cause, Its going to the shelf of forever putoff projects and the SMG version maybe coming back from the dead. I found out that my prototype could not work reliably for any period of time before a case would rupture in the chamber, because of my design. So I am now working on a new type of action which I call a semi-bolt. The new design will use a hexagonal receiver, which will mate with my barrel better allowing for more accurcy(sp). The action utillizes a closed locking bolt, where a bending bolt handle/dust cover folds forward and locks into the ejection port on the receiver after the bolt is released. Locking the bolt inplace till the bolt handle is gripped and pulled back unfolding the dust cover/bolt handle and unlocking the bolt from the receiver. Once the bolt is drawn to the end the empty case is ejected and hammer recocked. The bolt handle is released and the return spring rams the bolt forward putting another shell in the chamber and relocking the bolt unit inplace. I will be posting a diagram once I'm done drawing it to explain the princible.

[Nico]

For those of you who have had trouble with 'genuine' AR-7's working properly, here is an article by someone who was able to work out the kinks: http://www.alpharubicon.com/leo/ar7gm32.htm