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Here's the start of my rec. welding jig. It's made up of two parts, front and rear. The rear square section rides in the bolt rails. it's cut to approx the same dims as the bolt. I used some 1"x1.25" bar stock. The front section was made from 1" round stock. I just need to turn a bushing for the front barrel support, and I need to add some stops to set the length. Other than that theres not much to it.

Great idea none!!
It the OD of the round stock for the Front barrel bushing?
I can't remember, but the barrel gate door also has a barrel entry hole (size?), and
I think you're set if those two are the same dimen.

Looks like your on the right track. Great minds must think alike since I just logged on to post a pic of the same.

Here is a picture of the jig I use when joining the reciever to bbl jackets . You might consider machining a bushing for the front and rear of your jig, both the front of reciever and rear at stock area are both round.
I have threaded studs on each end of mine to controll overall length also. I like your sq section to engage the rails, I use some blocks drilled for my 1" rod that acomplish the same.

now thats a concidence

panaceabeachbum: i like the rear round section idea. As it was i didnt have a good way of aligning the rear (latch section) of the rec. That should work nicely.


Karbinator: I still need to make a bushing for the front barrel support. it's I.D. is approx 1.150". The barel gate through hole is approx 1.130"

none123 wrote:now thats a concidence

panaceabeachbum: i like the rear round section idea. As it was i didnt have a good way of aligning the rear (latch section) of the rec. That should work nicely.

Id like to take credit for it but I got the idea from Brian at BRP, he used to have pics of all their jigs and tools etc on the old site. I will try to find them since I am sure I mirrored the site somewnere. It works really well. If you look at the front of the buffer where the round step is you can pull the needed dimension for the rear disc.

I am currently working(slowly) on a reciever end only jig that will index off rail rivet holes, rails out, and should allow reweld of the IO type chopped rec scrap. Mainly just a large 3 piece rectangular block the width and length of the inside of reciever with tapped holes that align with rivet holes etc. The thought process is 3 piece so the center one can be pressed or pulled out of place and allow the 2 side pieces to easily be withdrwn. Probably could just be 1 piece but would suck to have it stuck in place.

If you can find them i'd really like to see the pics of the BRP jigs. I need to add some stops to my jig so that I dont need the trunion/cam piece to keep the relationship between the rail section and the barrel shroud correct.

I have not been able to find the hard drive with the pics from brps original site yet but will keep looking. If there are any dimensions you might need i have one of the BRP guns from a few years ago as well as a couple of brians 80% recievers and will gladly pull any needed dimensions , feel free to ask.

What else needs to be welded on the receiver that isn't mentioned?

Pirate wrote:What else needs to be welded on the receiver that isn't mentioned?

I love a trick question.

Is it the bolt block ??????

the older brp semi i have access to has the carrier block pin in rec, welded in place under cross pin for ground mount and then the gstick mount with cross pin is welded in place after riveting. Maybe overkill , newer 80% is the same way