Hello! I'm a Norwegian Redneck who purchased 2 lower receivers last year.
Project #1 was assembled right away, but #2 was not.
Attachment 33438Attachment 33438
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Hello! I'm a Norwegian Redneck who purchased 2 lower receivers last year.
Project #1 was assembled right away, but #2 was not.
Attachment 33438Attachment 33438
The crack goes all the way trough the receiver, the anodizing fills the crack.
So this happened early in the process.
Was thinking to make a dedicated .22 of it, but will it hold up .223 if properly welded?
A guy i know is like Master Yoda when it comes to welding.
Any input is highly appreceiated
Aluminum lowers are made from either the 6061 alloy or the 7075 alloy. 7075 is not weldable, and 6061 will have to be re-heat-treated after welding. This heat treating is not just quench-and-temper, but an involved precipitation hardening process.
Your crack is at a critical stress point. It looks to me like you should scrap the receiver.
thank you for your opinions, in Norway, the lower is the registered part.
according to website, it's 7075 T-6.
so, scrapping is an option. but i think maybe i can use it as a dedicated .22 trainer.
it's all up to master Yoda then.
when the lower cross the atlantic, it turns to silver.
after crossing the Norwegian border, it turns to gold...
i paid approx. $240 each, +approx. $70 tax (equalent to your tax stamp)
but got a full refund for the cracked part.
so, welding seems like an option -IF possible.
You are wasting time attempting to weld it. It couldn't be cracked in a worse place. There is no where to leave any added material. The front, back and top would have to be dressed back to spec and threads chased if he breaks through. Even if he gets the 7075 stuck back together it is most likely going to crack again. Throw it away.
You can build 22 rimfire out of it, but realize it will eventually get worse and finally fail. It may be possible to have a clamp machined to go around that part that will hold it together after the receiver extension is installed.
For your 5.56 rifle, get another receiver. I don't suppose you can get your money back on the cracked one...?
Thank you Sir.
Will scrap it and obtain a new receiver.
The source is dry, so i need to find a new supplier.
I wouldn't weld it, MistWolf has the right idea about making a clamp. You could probably use something like this Troy or DD sling adapter and drill/tap into the extension threads and use set screws to hold it in place. http://www.brownells.com/shooting-ac...prod27321.aspx or http://www.brownells.com/shooting-ac...prod40330.aspx
I like the Troy slingmount, but i found a supplier who got a shipment of Bushmaster lowers in transit.
It will be approx. $ 175 and the Troy slingmount will cost me $ 80.
The broken Stag will most likely become a lamp or something :-)
Beerman, if I'm understanding correctly, this sounds like a manufacturing defect. Have you contacted the manufacturer? If you explain the situation, perhaps the manufacturer will stand behind their product even though it's been a while since you purchased it. Good luck!
I got a full refund from the dealer, nice guy.
So i was just wondering if i should try to fix it or scrap it.
At this moment, i think it will become a lamp, wallhanger or paperweight.
If your good with a drill press you could run a 1/64" steel rod through the crack and possibly save the lower but like old cars. "You don't know what the problem is until you try and fix something". The company you got it from should honor the fact that your lower was broken before you used it and replace it. But if that doesn't work try drilling for a 1/64" hole missing the threads for the buffer. If the crack was lower down on the receiver I would tell you to take a 1/32" threaded rod to it if it would be clear of anything but in your case your you are kinda screwed if you can't do the repair and or replacement.
If you want to use it, and if buffer tubes and parts kits are less expensive than the other prices you've posted, I would consider a temporary/permanent fix by gluing a buffer tube in place using one of the metal-bonding epoxy cement products. (Here, an example is JB Weld.) It won't be ideal or elegant or as strong as new, but it might give you some long period of use, especially if you use it as a dedicated .22 rimfire lower since those see insignificant recoil or movement across the cracked area. If you go this route I would thoroughly clean and degrease both the lower threads and the tube threads, and glue the tube in place around the entire circumference, so that the strength and stiffness of the tube helps to minimize flexibility in the lower. I think this is more likely to turn out OK than trying to weld it, regardless of the skill of the welder.
I emphasize that this is a "hey, why not?" type project, but since you (1) are in Norway (not our current paradise of $50 lowers here in the USA), (2) have already received a refund, and (3) have a somewhat large cost to buy lowers - why not?
If it was me, Id permanently install a 7075 A2 RE, and I would TIG (or in your case hire Master Yoda) the flange of the RE around the entire circumference of the back of the lower, thus utilizing the material of the RE to add rigidity. 7075 is weldable, with a few ** behind it, depending on application.
You have nothing to lose, as you have already been refunded. I would bet money youd be GTG for thousands of rounds.
If it fails, then plan B would be make a .22LR pistol Sans RE.
YMMV, but this is what I would LITERALLY atempt with it, if your lower were in my hands. I certainly wouldn't scrap it, at the end of the day its a lower in your possession that's been transferred and paid for. Id hate to REMOVE a lower from the AR15 gene pool.
EDIT Wow, Ive been lurking here so long I didn't even realize this is my first post. I guess theres a first time for everything.
Christmas tree ornament.
As stated above 7075 is not weldable. If it were mine and I wanted to use it for a.22lr I would consider gluing a receiver ext in with something like Locktite 648 ( http://www.henkelna.com/industrial/p...=8797927964673 ) with a clamp to align the crack as best you can.
Set it up on a mill, drill/tap a set screw through there on an angle. If it breaks into the threads, clean up the threads. Then take the set screw out and relieve it so it doesn't affect the threads. Loc-tite for good measure. Then get back with us if/when it breaks again. I'd be curious how long it holds up and wouldn't be surprised if, with some thought, it turned out to be a non-issue.
Can always make a 22 receiver out of it, but that's no fun.