SL9 Airsoft AEG Sniper Rifle by Umarex

[wilekcmc]

This is on the H&K Full Size SL9 Airsoft AEG Sniper Rifle by Umarex sold by Evike. I don’t know where this topic is headed but hopefully I keep an open mind about it.

So in late fall of 2015 I bought the KWA G36 and the H&K Full Size SL9 Airsoft AEG Sniper Rifle by Umarex, always wanted these two so I got bought them. My first impression of the SL 9 was one of not bad nice polymer (hated the red tip). So I was basically happy with it. Then I notice that my thumb could not reach the select lever, not too happy about that. As I moved on I hooked up one of my 11V lipo’s and load the mag with .25g bb’s and wen to fire it on semi auto. At first the gun did not want to cycle properly then when it did fire it was not shooting well at all. But guess what than the gun stopped feeding, so I was like scratching my head to say HHHHHHHHMMMMMMMMM. Torn bucking on the very first try not good at all.

Ok Evike says that the inner barrel is 650mm long, this is very wrong the inner barrel is 660mm long and fits to the tip of the silencer, just being 10mm short cause the bb’s to hit the inside of the silencer. So I upgraded the hopup chamber with a ProWin G36 and a PDI buking.

If you use this Hopup chamber you will need to shim between the mechbox and the hopup unit it's self about .03mm or it will not feed at all.

More to come on the Mechbox later :banghead:

[Danke]

Ares the subcontractor?

[Cliffradical]

Yes. Last I did an SL9 by Umarex it was indeed an Ares. They are very nice in lots of ways, but being a G36 dressed in civilian clothing, they always came with a few groans.

[wilekcmc]

So the mechbox is a V3 with a micro switch, right out of the box there was an issue of semi auto firing. The reason for this was the mechbox was over shimmed from the factory so it would not cycle properly. Other issues with the mechbox:

Piston Head would not allow the O-ring to expand, the holes in the head were not cut all the way thru
Cylinder Head Leaks
Air Nozzle Leaks
Metal Spring Guide with washer

Good Points of the Mechbox:
Good Piston All Metal Teeth, already had the second tooth removed
All Steel Gears
Quick Change Spring Guide

Upgrades to the Mechbox:
Matrix CNC Aluminum Air Nozzle for H&K Umarex G36 / UMP Series Airsoft AEG Rifles
Lonex Complete Internal Upgrade Series Enhanced Cylinder Set for MK36C Airsoft AEG Rifles - Mushroom Type

[Covax]

FYI, not sure if others have this issue but I'm not seeing any of the photos.

Goign off topic for a sec: I've always been partial to the SL8/9 silhouette, even though I'm not much of a 'sniper' player (you can blame F.E.A.R. for that I suppose). Currently the Echo 1 MTC 3 my go-to carbine. Best lil' hybrid yet.

[Hectic]

I don't see photos either.

[ThunderCactus]

The barrel being 10mm short causes BBs to hit the silencers aperture?
So the BBs are leaving the barrel at a 3 degree angle?
I think there is something else going on there. You should be able to have a 100mm barrel in that gun and not have the BBs hit the aperture.

[lurkingknight]

I've had bbs hit the suppressor on my g36, doesn't happen all the time, but it happened often enough that it left marks/ fragments and foam bits. The more it happened over time the more foam bits started getting caught and compounded the issue.

On some g36s the inner barrel floats in the gas block/outer assembly. Some guns have grub screws to tighten the barrel down and most likely it's mounted on the bottom near the front, so that might be enough to cant the barrel upwards to cause a strike. I know they were hitting because there'd be a ping and you could see the flight path go off at about 30-40 degrees.

The fliers went away after I went to a K front end and added an appropriate barrel extension to cover the inner protruding from the gas block.

[ThunderCactus]

Hits DO occur, but it's never specifically due to the empty space between the inner and outer barrel.

[wilekcmc]

Originally Posted by lurkingknight

I've had bbs hit the suppressor on my g36, doesn't happen all the time, but it happened often enough that it left marks/ fragments and foam bits. The more it happened over time the more foam bits started getting caught and compounded the issue.

On some g36s the inner barrel floats in the gas block/outer assembly. Some guns have grub screws to tighten the barrel down and most likely it's mounted on the bottom near the front, so that might be enough to cant the barrel upwards to cause a strike. I know they were hitting because there'd be a ping and you could see the flight path go off at about 30-40 degrees.

The fliers went away after I went to a K front end and added an appropriate barrel extension to cover the inner protruding from the gas block.

There is space between the inner barrel and the outer barrel size that does cause some misses.

[wilekcmc]

I posted the photos on google photos and made them public, dont know why they are not showing up for you? If you know a better way to post photos please let me know and I will fix it ASAP.

Thanks

[ThunderCactus]

host to imgur?

Hits are possible, but it a 10mm distance? That is a phenomenally minuscule distance in which the BB can change course and hit the suppressor. Most likely, the inner barrel is misaligned, or there's a burr on the end of the inner barrel.
With a setup that's shooting straight, you can have over 300mm of distance between the inner barrel and end of the suppressor and never get any aperture hits.
Something else is definitely going on there.

[wilekcmc]

Originally Posted by ThunderCactus

host to imgur?

Hits are possible, but it a 10mm distance? That is a phenomenally minuscule distance in which the BB can change course and hit the suppressor. Most likely, the inner barrel is misaligned, or there's a burr on the end of the inner barrel.
With a setup that's shooting straight, you can have over 300mm of distance between the inner barrel and end of the suppressor and never get any aperture hits.
Something else is definitely going on there.

The suppressor on a SL9 is only 8.5mm opening to support the inner barrel, most suppressors opening is around 12mm which is allot.

Again How do I pos pics to show what I am talking about?

[Covax]

Originally Posted by wilekcmc

I posted the photos on google photos and made them public, dont know why they are not showing up for you? If you know a better way to post photos please let me know and I will fix it ASAP.

Thanks

If you're posting on a desktop you can upload the files on the post itself. When replying/editing, scroll down to "Additional Options" and you'll see "Attach Files".

[ThunderCactus]

To hit an 8.5mm aperture at 10mm from the end of your barrel, your BB would have to leave at a remarkable 7 degree angle (I did the 3 degree calculation for a 7mm aperture for some reason).
To put that in perspective, a total 14 degrees left to right of potential launch angle is a 48ft spread at 200ft.

The osprey suppressor I have on my M14 also uses an 8.5mm aperture all the way through (since it was for a power-up barrel).
Between the inner barrel and flash hider is 130mm
So for a BB leaving my barrel to hit the aperture that it's flying into, it would have to leave at a miniscule 0.55 degree angle.
But wait, there's more; it also has to fly down 200mm of 8.5mm tube, so in order for the BB to even glance off the very end of the exit aperture, it would have to leave my barrel at an angle of .217 degrees.
And yet, 130mm from inner barrel exit to 8.5mm suppressor entry aperture, zero hits. And through 200mm of tight 8.5mm tube, zero hits.

It is, most definitely, without any doubt, not an issue of your barrel being 10mm away from the aperture. Something else is causing that problem.
Most likely, the barrel is either held to center BY the exit aperture, and floats inside the outer barrel when it's not supported by the exit aperture, so the sag points the barrel right into the exit aperture.
Or, less likely, there's a burr on the 650mm inner barrel.
Could also be the threads for the suppressor are machined on an angle, causing the aperture to not be centerline.