Hangtight Posted May 18, 2017 Share Posted May 18, 2017 Seeing as bullpup AKs are a little thin on the ground, I'm just going to have to build my own. £30 at the local Airsoft car boot got me a somewhat unloved SRC RPK. It looked awful, but a fresh battery coaxed it to cycle and once it was disassembled it turned out that apart from a lightly stripped piston the internals are barely used and in great condition. A cheap (less than £20) AK rail was purchased from China. Which has had one of the parts reversed and is going to be used upside down... A quick rummage in the scrap bin at a local fabricators sourced a couple of bits of 2mm aluminium sheet, and then there was a lot of sitting and looking/thinking until my son suggested that I just 'Think like a Russian'. Simplicity wins the day, so out with the hammer... Link to comment Share on other sites More sharing options...
Hangtight Posted May 18, 2017 Author Share Posted May 18, 2017 Then there was quite a lot of cutting, drilling and filing... More updates when I can be arsed. Link to comment Share on other sites More sharing options...
Head Moderator Jedi_Master Posted May 18, 2017 Head Moderator Share Posted May 18, 2017 You do realise that the Bullpup design means that the gun's action parts (and magazine) and located behind the trigger assembly, as per the British L85A1 rifle. Yes, P90 does have top mounted magazine. It will be interesting to see how you reconfigure the gun. I do like the attached RIS. Link to comment Share on other sites More sharing options...
Hangtight Posted May 18, 2017 Author Share Posted May 18, 2017 Trigger extension is next. It might need a bit of CAD, which in keeping with the low tech 'Russian' approach in this case stands for Cardboard Aided Design. Link to comment Share on other sites More sharing options...
Hangtight Posted May 19, 2017 Author Share Posted May 19, 2017 Or I could just get a BTC Chimera and fit a slave trigger switch... so hours of twatting about for a mechanical set up that might not ever work properly or buy something that is easy, has umpteen fire control modes, pre cocking, ROF control, battery protection...Hmm. Link to comment Share on other sites More sharing options...
Sacarathe Posted May 19, 2017 Share Posted May 19, 2017 SRU makes kit for a bullpup AK. Link to comment Share on other sites More sharing options...
Hangtight Posted May 19, 2017 Author Share Posted May 19, 2017 47 minutes ago, Sacarathe said: SRU makes kit for a bullpup AK. But only for a couple of models of GBB rifles as far as I could tell. Plus it looks like it fell out of the sci-fi ugly tree, and hit every feckin' branch on the way down... Link to comment Share on other sites More sharing options...
Hangtight Posted May 19, 2017 Author Share Posted May 19, 2017 Can I get a V3 BTC Chimera anywhere, including the States? Not a chance. Until I check the classifieds on this here forum. Brand new, unused and posted for the sake of poking PayPal with a stick. Be rude not to. The only problem is if I decide I want them on the rest of my guns. That could get a bit expensive. Link to comment Share on other sites More sharing options...
Hangtight Posted May 21, 2017 Author Share Posted May 21, 2017 Bit more tin bashing done... The butt plate will hinge and latch (at least it will once I've made it) off the motor cover, covering and holding 2200mah lipo bricks. Link to comment Share on other sites More sharing options...
Hangtight Posted May 23, 2017 Author Share Posted May 23, 2017 Not the prettiest, but it'll work. Link to comment Share on other sites More sharing options...
Hangtight Posted May 24, 2017 Author Share Posted May 24, 2017 Stockage ... Plenty more Dremel abuse and sanding to do yet. Link to comment Share on other sites More sharing options...
Hangtight Posted May 24, 2017 Author Share Posted May 24, 2017 I'm sitting here looking at the stock and trying to decide whether I like it or not... maybe something simpler. Link to comment Share on other sites More sharing options...
PopRocket123 Posted May 24, 2017 Share Posted May 24, 2017 I think it's a little fat. Any way to slim it down? Link to comment Share on other sites More sharing options...
Hangtight Posted May 25, 2017 Author Share Posted May 25, 2017 The reach was too long and I didn't like the foreend.... So I threw it away and started again. I've made a new trigger box that fits up inside the rail section which is cut away. So the trigger sits much closer to the barrel and the grip can move back towards the magazine. I Hacked the grip off my previous effort to mock things up. Link to comment Share on other sites More sharing options...
Hangtight Posted May 25, 2017 Author Share Posted May 25, 2017 The grip is short, but still comfortable... A tweak to the mag catch means the mags rock in and out easily Link to comment Share on other sites More sharing options...
Hangtight Posted May 26, 2017 Author Share Posted May 26, 2017 Nailed it... I don't know why I didn't think of this before. I've had the rail kicking around for a while, but this morning, for some reason I saw it in a different light. So I chopped it up. Im not going to be short of rail space. Link to comment Share on other sites More sharing options...
Hangtight Posted May 26, 2017 Author Share Posted May 26, 2017 I've decided it's an AK7, cos it's like an AK74 but shorter... Link to comment Share on other sites More sharing options...
Head Moderator Jedi_Master Posted May 26, 2017 Head Moderator Share Posted May 26, 2017 1 hour ago, Hangtight said: I've decided it's an AK7, cos it's like an AK74 but shorter... The new AK(20)17. It should look good (or at least matching) once painted. Single shot, semi, or full automatic? Link to comment Share on other sites More sharing options...
Hangtight Posted May 26, 2017 Author Share Posted May 26, 2017 It's going to have a Chimera ECU, so semi with pre cocking, three round burst with a trigger tap on auto and full rock and roll if you keep the trigger down. Link to comment Share on other sites More sharing options...
Hangtight Posted June 1, 2017 Author Share Posted June 1, 2017 I've finished cutting, filing, drilling and tapping... Bits, and pretty much all the tools used to make them. Assembled. Enough space for 2200mah 11.1v lipo bricks, and the spring latch makes them easy to access. Paint next. Link to comment Share on other sites More sharing options...
DarkAssassin Posted June 4, 2017 Share Posted June 4, 2017 Really looking forward to seeing the finished article! Link to comment Share on other sites More sharing options...
Georgeturner2001 Posted June 4, 2017 Share Posted June 4, 2017 Looks really good so far! Link to comment Share on other sites More sharing options...
Hangtight Posted June 4, 2017 Author Share Posted June 4, 2017 Ta. The irony is, sorting out the rubbish standard bits is proving harder than the conversion. At the moment I'm on my third version of trying to stop the top cover rattling and the fake bolt/hop up cover wobbling all over the place. Paint may have to wait until I've stopped taking the thing apart every five minutes. Although if anyone has any tips on getting a blued steel paint effect, I'm all ears. Link to comment Share on other sites More sharing options...
Hangtight Posted June 5, 2017 Author Share Posted June 5, 2017 Last bit of fabrication. As standard the top cover rattled and the fake bolt flaps around all over the place. I've made a small block that is epoxied into a gap in the receiver onto this is bolted a strip that bears against the top inside face of the bolt stopping it tipping inwards. The bolts also locate the recycled leaf spring that used to fit under the rear sight. This pushes up on the inside of the top cover, holding against the metal of the receiver. No more rattle. There's a bit of fiddling around getting wiring into place and then at last I'll be able to get rid of the blue! Link to comment Share on other sites More sharing options...
Hangtight Posted June 6, 2017 Author Share Posted June 6, 2017 I threw together the gearbox today to see what the SRC Ultra High Torque motor was capable of. 7.4v, 18:1 gears, M100 spring, 12rps and pulled 24A doing it! No wonder the motor gets warm. That's really poor performance for something with such strong magnets. And I know I said the gearbox was thrown together, but it was decently shimmed and lubricated, I just didn't spend a lot of time fine tuning. So a SHS HT and 13:1 gears are on the way, along with bits that are definitely better than the very average SRC internals. On the plus side, the BTC Chimera is an awesome piece of kit. I want them in all my guns. The pre cocking is fantastic. I was monitoring the piston position and it is absolutely spot on every time. You can set it right to the point of piston release which means the trigger response is instant. Love it! Link to comment Share on other sites More sharing options...
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