RE…Building my DMR Blaster to Milsim Spec

A long long time ago, I bought my first AR15/M4 variant gel blaster. A Jinming Gen 9. The first decent quality M4 available for the time in early 2019. I have written about then Gen 9 before in TSI Magazine.

 

Recently it has evolved again. Gone with the nylon receiver and nylon gearbox. Now an Aluminium receiver and CNC aluminium gearbox housing from Aztech Innovations.

In its prime the Gen9 was built by Shakkas Clakkas running 35 rounds per second and 330 fps which was quite advanced for its time being run by a Gate Aster mosfet. It was very good, accurate and great range. But eventually the nylon gearbox wore out to the point of massive pressure loss and low FPS, so it sat on the rack for nearly 12 months, so now is the time for a rebirth.

With my preferred event style being the long days out in the bush playing the Milsim style game where power and gels are limited I needed to slow the rate of fire and set an FPS level to maximise range and accuracy. Sticking with the same Midwest Industries metal forend and surpressor it has a defintely DMR (designated Marksman Riflle) look to it, previoulsy referred to as 50 Shades of FDE,

now named...Demi!!! For the new build we decided to use some of the original parts, ie the SHS 12:1 gears that were always in the Gen 9 as they were still in perfect condition from when Shakka of Azraels Armoury build it 2 years ago. Being that I wanted to have this one built to max reliability I simply couldn’t resist going with the new the Aztech Scythe CNC gear box from Azraels Armoury. Aztech have made the housings using the strongest aluminium the machinest could CNC which is 7075 grade and have completely knocked the ball out of the park. These are designed to run the super high quality APS internal gear box parts. With the old setup being Jinming Gen 9, we had to change to a new APS cylinder and head, nozzle and tappet. As I wanted to slow the rate of fire right down from the 35rps to conserve ammo and reduce power consumption we opted to use the old 12:1 gears with a slower torquey and super low amp draw ASG Infinity CNC 18k rpm motor, chosen purely for the long life and ultra reliability of the worlds most proven 480 Long motor brand.

The Scythe gearbox was again screwed together by the one and only Shakka, no one else touches my shit, when Shakka builds a box you can have absolute faith in his incredibly meticulous detail. Unfortunately for Shak the Scythe isn’t the perfect match to the metal WAT receiver I got for it, which meant Shakka had to dremel away some meat from around the T piece of the WAT receiver to ensure a nice snug fit with perfect t piece alignment for magazine fitment and feeding. Fortunately Shakka is he best in the business, so he didn’t even try and fire it prior to cutting away some meat, he quite simply knew it was going to need the touching up. When I bought the receiver there wan't man other light weight options on the market, whilst it feels ok in the hands, I really hate the WAT text and gastly looking QR code on the side which is now blacked out as a temporary cover up. Hoping to get rid of it more permanently some how.

 

Whilst in the gearbox Shakka was very naughty, he opted to change out my Gate Aster Mosfet for some thing else he had lying around, when I say lying around I mean it, he has spent so much money on parts for testing and learning purposes, every thing that comes to market he buys and test, in his words “he cant recommend parts to customers if he hasnt been there and done that”.

So Shak literally has boxes of working high end parts in his tech room not being used. So the Aster didn’t make it into the Scythe, instead a lightly used Jefftron Leviathan went in, Why? Well mostly because he wanted to be able to run the bluetooth connection for diagnostics and ease of tuning in the field. The Aster is cable managed and just a tad less user friendly than the Leviathan. When I found out that the Levi went in, I struggled to hold the smile for the telling him off for doing it. But I am forever thankful.

 

So what is the actual spec list? well here goes nuthin:

-Aztech Scythe 7075 CNC box -Leviathan Mosfet -SHS 12:1 gears -ASG Infinity 18k CNC -Aztech Innovations 440c Stainless bushes -Aztech V2 Spring Set -Aztech gen 1 Speed Trigger -APS 70% ported Cylinder -APS Cylinder head, Nozzle and Spring retainer -SHS Piston and Head Short strocked 3 teeth. -APS mag terminal wiring and plate -Fighting Bro 31cm Tight bore Barrel (measures 7.15mm Internally) Now an Aztech 7.25mm -SHS M110 Spring

-APS Overload grip as Shakka just couldnt get the pinion to bevel mesh nice with the XPower Tan grip I had,

Pictured here with my EMG Falkor Blitz converted to lightweight stock used by Lucas C-4 #crazmaniac the Falkor is considerably heavier with the chunky reciever and forend.

The end result is 325fps, set for Milsim events as the ideal FPS for tuning accuracy. Like all my blasters it has an #Azteck #Muzzletek hop up unit to dial in the max range and reduce grouping size. Currently it is running reasonably consistent 44m-50m with 7 out of 10 shots being accurate enough to hit a man size target. Which isn’t perfect, I would like to dial that in a little more, but with the current market shift to the new #Ausgel Elite gels Im pretty confident I should be able to find a sweet spot to halve that grouping size at around 35m.

The #ASG Infinity motor draw a ridiculously low amount of power, just 15 amps on full auto and 25amps on semi auto. The motor barely gets warm in the hand as its not working hard t all pulling the M110 through the 12:1 gears. It really is a high quality piece of kit.

With Elites being so new we were not too sure yet if they perform best through a tighter or looser barrel. Definitely harder than AKA gels, but on average slightly smaller, they may work just as well through the tight barrel.

My theory goes a little some thing like this: -they are smaller than AKA to start with so they don’t have to compress as far for the tight barrel, even though they are harder than AKA they are smaller so the hardness to squish ratio is probably about the same which hopefully means we will see a good increase in accuracy using Elites as they hopefully wont loose shape in flight as much thanks to being harder and also more consistency in accuracy thanks to more consistent in size.

But one thing I learnt at the 3 day event, tight bore barrels are not ideal for Milsims. You may go hours with out shooting a gel, that means the surface moisture is long gone and the are essentially dry. A tight barrel certainly out performs a normal bore barrel when the gels are wet or moist, but not when the gels are dry on the surface. In fact it was a pain in the arse, the dry gels really slow down in a tight barrel to around 150fps until it lubes up a bit, I was having to regularly add water to the gels in the mag to reduce the issue. Lessen learnt. I now have an Aztech 7.25mm stainless barrel installed ready for re testing.

My normal setup is to have the muzzle and hop up covered by a suppressor cover, this is my preference in look but also to protect the hop up. The last thing I want is to put the muzzle to the ground or bang it on a tree and damage the hop up affecting accuracy.

 

For the Combat Simulations milsim event at Susan River I mounted up the same Bushnel AR Optics 4.5-18 power rifle scope used on the Tavor previously, no this isn’t for rifle aiming and accuracy, this is a gel blaster. But it is for recon and being able to see a bloody long way and very clearly across the wide open spaces of the milsim venue and im happy to say I definitiley utiilsed the clarity of the little scope to "glass" across the open fields.

 
 

The rifle even though reasonably long was light to carry, balanced nicely in my arms when patrolling and comfy to carry. Range and accuracy was great when gels were wet. Unfortunately part way through day 2 the mosfet threw an error code that I couldn’t fix in the field, so Demi did get bagged up and I pulled out my little caramello APS MPX "Tissi" for the rest of the event, I swapped out the red dot for my scope and carried on. The one thing I did notice is the MPX is massively heavier than Demi and the shorter AOL made it harder to balance in my arms when moving making it definitely better suited to CQB style game play. The shorter tight bore barrel didnt have such a noticed effect with dry gels seeing decent range to 35m at just 280 fps and just 13cm barrel.

 
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