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vergessen
January 25, 2013, 09:26
https://lh3.googleusercontent.com/-O-VxGXKxcqA/UQKQzCS1dwI/AAAAAAAABrk/LzIFeSytJyk/s786/2013-01-25_06-26-49_735.jpg

So here she is, _amost_ done. I'm missing a locking shoulder and the buttplate, the latter of which is on its way. It was a little bit of a learning experience for sure, and I dinged up some areas where I made some stupid mistakes, but hey, that's the part of learning.

Built on one of the Coonan Argy receivers that Sarco is advertising. For the life of me, I could not get the barrel to hand time past 10:00. Even after putting it on the lathe and taking .002 off the barrel shoulder and getting it into the magic triangle, we could not get it fully indexed, even with the torque wrench set to 150 ft-lbs. All in all we ended up having to take ~.0035 off the shoulder to which point it would hand index to at least 11:40 and final index was achieved at 120 ft-lbs.

Also, one thing I'm still having issues with is one of the two pins on the cocking handle. One of the pins (which I used to hold in the spring and plunger) fit just fine in both holes. The second pin seems like it's just a hair larger and doesn't fit either. I had to file a small notch in the square button-like piece that fits into the cocking handle so that the pin [that would fit] had clearance. I don't believe this is a pin to anything else as my lower came completely assembled and not stripped, so I'm not sure what to do. File or drill the pin hole larger or try to find a different pin?

Roadmarker
January 25, 2013, 09:42
Sweeeeet, thanks for clueing us in on your refinishing technique on the SHOW US SOME WOOD post. Bad news is that you're gonna have to take more pics....but please put a mag in it, it looks naked without it. You sir have committed a mag foul. ;)
A very nice looking build, like I said more pics, closeups too. Also a range report after you get it on paper. We don't ask for a lot, huh? Do you have the bug? Are you planning another build?

vergessen
January 25, 2013, 09:57
Sweeeeet, thanks for clueing us in on your refinishing technique on the SHOW US SOME WOOD post. Bad news is that you're gonna have to take more pics....but please put a mag in it, it looks naked without it. You sir have committed a mag foul. ;)
A very nice looking build, like I said more pics, closeups too. Also a range report after you get it on paper. We don't ask for a lot, huh? Do you have the bug? Are you planning another build?


Heh, yea.. I have the bug, as there are a STG58 and a polish underfolder kit sitting in the manroom just waiting for the attention. :D.

I know the picture is a bit off.. it was the best as could be done at 6am(ish). I do need to go over it again and ensure that I didn't miss anything. I tried inserting a mag, but the one magazine that I do have (that's not currently disassembled) won't lock in place, and I'm not 100% sure why at this point.

And yea, as I said, I made some mistakes putting it together resulting in some dings (ie, on the end of the charging handle), but nothing that a very light filing and repark won't solve.

Range report will be posted once I get the locking shoulder and a little more .308 as the M1A got hungry and make a snack of my stock of Radway Green :rofl:

Roadmarker
January 25, 2013, 10:00
There should be a saddle notch on one side of the charging handle T lug to accept the pin. Don't forget to flare the ends or it might wander off after a few shots. Others have used a roll pin - (Roll pin size for plunger is 5/64 x 1/4. Roll pin size for T lug is 5/64 x 5/16).
You can also use the T lug pin for your gas tube.
Here is a link for a custom search engine for the FAL Files. Save it in your Favorites. http://www.google.com/cse/home?cx=016627024816471058913:jrp-_hjyone

Fiorina
January 25, 2013, 11:05
My argy kit was the same way. Also on Coonan receiver. I had to shave a little off of the barrel shoulder to get it to time properly. Im waiting on a .253 locking shoulder as well which is pretty small. As for the pin being too large for the cocking handle, also had that problem, I just found the right drill bit size (dont remember what that was) and drilled it out. Fits great now. You will also need to file your own notch into the T lug. This is easy enough, I just put it in and stuck a pen through the holes on both sides of the handle for reference marks. Check it often to see if it will fit.

Fiorina
January 25, 2013, 11:06
Not sure why the T lugs came that way, but they have no notch for the small pin

littlematt
January 25, 2013, 13:06
that's a pretty rifle

garyd1961
January 25, 2013, 14:18
"Built on one of the Coonan Argy receivers that Sarco is advertising. For the life of me, I could not get the barrel to hand time past 10:00. Even after putting it on the lathe and taking .002 off the barrel shoulder and getting it into the magic triangle, we could not get it fully indexed, even with the torque wrench set to 150 ft-lbs. All in all we ended up having to take ~.0035 off the shoulder to which point it would hand index to at least 11:40 and final index was achieved at 120 ft-lbs."

This doesn't sound right. I wouldn't have thought hand timed to 11:40 would have torqued to 120 ft-lbs. Did you mean 10:40?


















. I don't think 11:40 hand timed on the shoulder would have torqued to 120 ft-lbs.

vergessen
January 25, 2013, 14:57
Maybe I'm not expressing myself correctly here. My understanding (from reading here and from Gunplumber's video) is that the center of the small flat of the barrel should hand time to around 11:00, essentially forming one of the "legs" of the magic triangle. When we took .002 off the shoulder it would hand time to right around that point, but on setting the torque wrench to 120 ft-lbs it wouldn't tighten much past that point... maybe halfway from the starting point and the final 12:00 indexing point. Increasing the torque to 150 ft-lbs didn't increase it that much.

So we took the barrel back to the lathe and trimmed off another .0015, which then allowed us to hand time the barrel to the point where the short flat on the barrel was "skewed" to the point where the middle was 3/4 of the way from 11:00 to 12:00. We were then able to torque it down to 12:00 with 120 ft-lbs dialed in on the wrench.

So, unless we did something incorrectly (maybe had the receiver portion of the barrel vise too tight?), does that help explain what we did more?

I wish I had taken pictures of our progress.