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· gunco irregular
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Discussion Starter · #1 · (Edited)
As a shout out to VZ58 and his "how I rebuilt my milled ak's for $55" thread stickied above, here is a M70 reweld that got test fired today. Made the sideplates about 6-7 years ago, along with the barrel. Been sitting on a shelf since then but with the corona shutdown our governor implemented it gave plenty of spare time to dust off old projects. Dovetailed, then mig welded in a piece of 4130 to make the ejector from. Welded on the left side repair plate from the inside, then the right from the inside. Cleaned up the welds with the mill. Welded the outsides and cleaned up the welds again with the mill a couple thousands proud then used die grinders with 2" roloc sanding disks to blend the welds. Used woodruff/keyseat cutters to clean the weld out of the rails and the rest of the inside. Added a scope rail for a Zrak scope which requires a 8mm slot be cut in the left side of the receiver. Finished it up earlier today enough to test fire it. Now to strip it down for parkerizing and find where I put the cleaning rod 7 years ago.
 

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· gunco irregular
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Discussion Starter · #3 ·
Used a Hobart 210 mig to weld that one up. Much easier to get a good weld than the HF fluxcore welder that I've had for 20 years. Probably about as close as you're going to come to a metal caulk gun. Pretty much followed VZ58's thread except I'd made the rails as part of the repair plates and used a mill to clean out the excess weld which made it much easier I think. Few more weld pics. Pics don't show the seams "V"ed out but they were just prior to welding.
 

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· gunco irregular
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Discussion Starter · #5 ·
Thanks Gary, hope all is well out west. The first one I attempted 15-20 years ago didn't turn out nearly so well so I was elated when this one went together so nice and easy. It's been hot and humid here in MI (not AZ hot though) so I haven't been working on #2 much past where it's shown above as the lower receiver in post 3 pics 2-3. Going to end up as a M76 clone with M76 furniture but on a m72 type receiver (no top cover lock). Turned and chambered the barrel for it in 2014 also. After that There's still a M70 and M64 pair of underfolders to reweld. Will have to make more repair plates though.
 

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· gunco irregular
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Discussion Starter · #7 ·
The M70 had an occasional short stroke that I chocked up to very tight rails. The more it got shot the more it began short stroking until it stopped cycling altogether. More than enough gas and the rails had been loosened up a little so time to pull the gas valve and replace it. Sure enough the gas valve looked like a goodly portion of it's diameter had rusted away, it's bore in the gas block was oval and looked like the inside of a very old cast iron pipe. I believe initially there was enough rust in the gas block to seal up the valve, but the more it was shot the more the rust and crud got blown out until it leaked too much. Using the the grenade sight that is attached to the valve as a handle you could move the valve back and forth 1/16" on the head side and almost 1/8" on the nut side which it wouldn't do before. Made a new simple oversized valve out of 17-4 SS and reamed out the gas block to .4067" (closest reamer to the AKbuilder oversized .402" valves that I could find in the shop) so the valve bore was smooth and round and the .406" valve would just fit and turn smoothly. It's back to being a brass throwing machine. The head and nut will get thinned a little before staking the gas valve nut on for good. Several places sell replacement gas valves in different sizes if you need one and don't want to make your own.
 

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· gunco irregular
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Discussion Starter · #9 ·
Don't think a standard sized new gas valve would of worked as well for me either since the bore hole was oval on one side. I have an unissued Yugo SKS and had thought about just making a new gas valve for it out of SS. The M76 gas block for the next one has SS parts on it or at least chromed parts, but I've got two UF to do that will likely need new gas valves also.
 

· gunco irregular
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Discussion Starter · #11 ·
Guess what this moron is up to? :D

They still need a lot of chips to come off of them but I started the next set of plates. Three M70 and three M64 . The power feed limit switch on my 9x49 mill crapped out on me so I'm using the bench mill. Got these as far as I want to with the bench mill and will wait the couple days until the switch shows up so the slotting and contouring can be done on the bigger 9x49 mill.

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· gunco irregular
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Discussion Starter · #13 ·
Made some more progress this week on the M70 repair plates and am close to having six M70 sets done. Decided to double up the number of plates to have extras. The bottom sections are still the thicker magwell thickness the full length and will need the rear section for the FCG thinned out and an ejector welded in on the left plate to complete them. Perhaps a little deburing too. Pic1 upper 6mm rail/slot cut, faced cut on outside, top and bottom sides. Pic 2 bottom rail cut and thinned to magwell thickness. Pic 3 just shows a plate with the FCG area thinned and the ejector welded in. Pic 4 shows how the rails fit to the BCG.
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There are also the start of 6 pairs of M64 plates. 3 have been faced on the outside and top and bottom, 3 are just cut to length so far. Still deciding on how accurate I want to make the lower rear lightening cut on the left plate.
 

· gunco irregular
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Discussion Starter · #14 ·
Started a "couple" more since I was out again. Same basic style but divided between specific plate sets for Yugo M64, M70 and Polish. 1/3 of the way though slotting the upper rails for the Polish and M70 plates, which also get trimmed. Because of the lightening cuts on the outside the M64's have a little different slotting setup. Middle pic of the upper rail slot being cut has a lot of steam coming off the cutter from the water based flood coolant so the pic is blurry vs afterwards where the cutter is cool. That's a fair amount of chips on the vise though from just one rail.

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· gunco irregular
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Discussion Starter · #15 ·
Finished slotting the upper rails on all 57 of the plates... Took about 7 hours total over two days just cutting the slots plus cleaning the chips up twice. The ones sitting on top of the stack are M64 left sideplates. The bottom plates will eventually be Yugo M70 right and left plates, M64 right plates and Polish 1960 right and left plates.

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