Polish build kit follow up and completion

Well i had my video series on Kalash and Brass so while i finish having it edited, I thought I would fill y’all in. Above is a picture of the kit on the work bench. It was a bit exciting with the build about to commence. Everything is ready why all the parts. Once I assembled all the needed parts together on table it was time to start the video. In short we matched up the front and rear trunnion with the receiver and make sure our fit was correct. After that we then started the process of dimpling the receiver. In this way we had the metal on the dimples on the receiver. This way the dome-shaped rivets have a nice surface to bond with as we crush it it will fill that empty space and form a uniform rivet. After this process was done folding the metal for the rivet holes. Then came back with a rat tail file to make sure that any excess metal was shaved off. This is a hand fitting process and it took some time. Slowly but surely we got it all done and from there we went ahead and test fit it one of the long rivets for the back rear trunnion portion.

Once we know we had a nice perfect fit with very little wobble, we then proceeded to get the AK Builder rivet Crusher in place in line everything up. Once this was done we then proceeded to smash good old rivets.

As you can see above the rear tail rivet that is long, came out perfectly. Uniform in shape and flush to the receiver itself. The empty void space that was below filled perfectly and with a nice tight fit. This is the most important river that has to be crushed so that your other rivet holes can be put together and place without any worry of wobble. So this helps with making sure you don’t egg hole out the other trunnion holes.

As you can see above in the photo I perform the same work on the second rivet hole but as you noticed it is pretty much raised out and not uniform. This is happens when there is not enough support because of the nature of a underfolder and the rear trunnion being thin metal in the front portion of it. Using a block jig that I can slide for different heights back and forth I support the metal and allowed it to be crushed uniform. But before we can do all that I have to remove the rivets that I messed up.

Using the mill that I perform the drilling process to make sure the holes were uniform in the correct size. I proceeded to shave off the old rivet and knock them off. After this was done I went back to the process of crushing the new set of rivets into the holes. Unfortunately I didn’t snag a picture of this but it’s definitely in the video that will be edited and upload it soon. After this procedure was done I repeated it for the rest of the rear trunnion holes.

As you can see above they are crushed correctly in flush. One of the rivet present a problem to me with the rear training portion being dimple or bent in slightly. There was a small ring but not really noticeable from a far. This sometimes happens with under-folder since it’s not all one solid piece but it does not impede the function and the rivet was crushed to spec so that it will not interfere with long-term in the picture above you can see that the inner portion of the receiver the rivets are a circular disc that is smashed fleshly and evenly across. It’s very important because this will either make or break your receiver if you decide to use it over extend it. You can experience cracking and rivet wobble.

The next photo above is the completion of the front Trunnion fitted the same way as the rear end drilling into it. Once you use the AK Builder tool front tray and holder it was straightforward and test Drilling the front train with the mill then sliding on the receiver. In and out with out any fuss. Once you drill the holes perfectly these are the Flathead versions so they do not require the dimpling other receiver to work.

We do the same process of crushing them with the AK Builder tool and the process is the same using a 12-ton 20 ton press we made sure that they were crushed uniform and evenly. I highly advise having a second person who will pump the press while you hold the receiver in place and Visually guide them and how many strokes are needed. The beginning stroke on the 12 ton or 20 ton press may seem like it’s not moving but as you feel more resistance and it it will start giving way. It would then become really easy as you proceed forward. Towards the end of the crushing of the rivet it will give you more resistance with a 12-ton pressed Buffet 20 it will seem smooth and fluid.

As you can see above these are perfect rivets that have been crusty receiver. I would say it is Factory looking. This whole build process if done correctly will take about two to three hours. If you run into any issues take your time be patient and work the process. The easy part is getting the receiver together the tuning portion will be for your rails for the bolt carrier and the extractor claw headspacing is really easy just make sure you have your bolt in place and do your twisting back and forth on it to make sure it’s closed properly and if you want a tighter fit. I’m for the latter end of a tight fit Bolt. Preference but you can decide on your own as long as it close completely in the lock and groove.

The same as we did for their front you can see that these are perfectly Crush rivets and they look near Factory. From the outside portion of the rivers to the insides are crushed correctly and perfectly. In the video. Post in the future you will see more. And me verbally explaining everything as we go along in the process of the build. For now look at the pictures and how it looks. This is the same as the previous video series and I explained about the process itself and better detail the video. The next photo you will see is of the assembled Barrel that is pressed into the receiver.

It’s always good to have a good friend give you a helping hand or that third hand as they say. Also have something to protect the crown the most pennies for your thoughts, come really in handy. I have my friend Tom give a slight demonstration and how it’s going to look when you press the Barrel in. The first photo shows him using the penny as a crown protector for the barrel and the second after the barrel and headspace were the bolt that was near us is the barrel pin being pressed. Using Lube on the barrel and using lube on the barrel pin is important. You don’t want to t gall to the metal or cause it to go in croked and possibly cracking their front trunnion. This is very rare but it happens on machines at factories versus with a hand-crank we can back off and try again. Be patient also make sure your measurements are correct for the barrel Journal size and the journal size of the front trunnion. Off by a couple thousands is okay nothing more though. After we did the final touches on putting the barrel pin in with the Press we have a complete receiver just have to add your parts like your trigger assembly, safety selector, hand guards and the folding stock. Also I did not mention that we install the trigger guard and latch rivet into it. Basic a plate push down to the jig and Crush below you will see the final photo before we did all the accessories

Once everything was done it was a matter of just patiently putting it all back together. Snakebite is real with those springs for the AK-47 and its variants. Always have a shotgun shells housing on hand to tame those little Vipers. You do not need to pay the blood price on your first time just saying. After you have a assembled everything and taking your time with underfolder. You’ll need to assembled the folding stock, there are three pins one that goes across one holds that the assembly the second one is behind it on the outside ring that is twisted on and then the pin is through shot through. After that the other side of the internal mechanism and you’re done. I’ll provide some nice pictures of the final product and for your viewing pleasure. I know this is a lot to read and maybe a timer for work I hope you enjoyed it and the video will come soon.

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WOW, what a fantastic/thorough post!

Be sure to link the finished videos :sunglasses:

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Amazing writeup!

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:+1: :+1:

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So is that a Bridgeport you got there? Nice mills! I worked on them for a while, then went on to horizontal boring mills. Would be nice to have a small vertical like a Bridgeport with DRO.

DSA/dnc IS the greatest enemy of the USA in the world…next to the scotus!!! And they will prove it inn November!

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We are waiting for the range report. How does it run?

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The range report will be this weekend with some video. I’m going to make sure that it gets excited shoots in and then from there give me some nice little shooting montage. Yesterday my pin retainer plate came in so it will function without no worries. The only thing that’s not original is it trigger that is from ALG and it is nice. A big shout-out to recreatorblanks for making such a precise receiver from sheet metal

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You are correct sir it is a Bridgeport drill Mill. I do not have a Dro on it but it is my friends set up so he’s working on it in the future. I remember when he got it and him doing the setup. Let’s just say it’s not light but it’s a champ and it puts out great quality work especially making his own tooling. It benefits me of well so I can get some nice cool parts that may not be available or solve a really nietsch problem

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Yup thought so. With a good toolmaker’s compound vise and good rotary table there really isn’t too much stuff you can’t do with that little mill.

DSA/dnc IS the greatest enemy of the USA in the world…next to the scotus!!! And they will prove it in November!

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Well today I decided to change things up. After work I decided to make a trip out to the range and see what this underfolder could do. The results were very surprising. Even with the stock has a little bit of wobble in the fix position, bracing it tightly to the shoulder it worked out pretty well. The first photo will be a tragedy and then you’ll see the progression to being cleaned up with a proper zero.

This photo above was the first shot at 50 yards. It started out as a nice-sized fish group at the 11 position from the center. After that I’m a small adjustment and walk it over the outside for bulls eyes are the results of trying to find that sweet spot. This went on for about 30 rounds. The next photo below will show you the results of toiling with the front sight.

It worked out pretty nicely in the end. Letting the rifle cool down a bit there was a shift in the zero when the barrel got hotter but not enough to called alarm. I repeat this process for a few more sessions on the remaining bullseye’s on the paper Target at 50. Once confirmed this bill worked at 50 yards and then took it to the hundred yard line. Once I have my setup complete and I had my State of Mind focusing on the trigger squeeze and the shooting fundamentals the results speak for themselves.

This was the first group at a hundred yards after I let it cool down a bit. Some say AK cannot be accurate in that is a lie. I did this with a basic unmodified underfolder minus the trigger. The following groups were consistent with the first one and a hundred holding about a 2 or 3 MOA on average. Overall I’m very satisfied with this rifle in the performance for what it is. Compact durable and can take a beating when needed. Eventually I’ll try to get it set up so that it can do some bump firing or you can see my PAP M92 for that whole Fiasco of loudness.

I hope you enjoy this little range report in the future some more sessions with other bills I’m working on. I now have my own producer section on full30 posting there from now on four things that are involved with kalash and brass

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Gratulacje! Great job on the build :+1:

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If that means great post I agree, well done!

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It translates to “congratulations” :wink:

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Well yall asked for it and its up

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:+1: :+1:

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Good to see it is running well.

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Thank you I wanted to use Tula as the base testing ammunition because if it can run that crazy stuff then it can run just about everything else. With that said it well and even though the ejection pattern was sporadic and it did so far still cycle

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Great work @MikeBlack47!

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