|February 27th, 2008, 23:29||#1|
Delierious Designer of Dastardly Detonations
Join Date: Dec 2001
Location: in the dark recesses of some metal chip filled machine shop
Impressions on Systema's new MP5 PTW
*reposted from Airsoft Mechanics where I also visit*
I've finally gotten some help handling my ShotShow photos.
I got to see the new SystemA PTW and even partially disassemble it. Because Kumi brought only one prototype I had to resist completely taking it apart for fear that I might damage their only showpiece. Still I saw a few interesting things.
Wallace and Kumi showing off their Revolution gearbox and shiny new PTW MP5
Side by side comparison of M4 and MP5 cylinders (top to bottom respectively)
It looks like there are a few differences between the two cylinders that prevent cross compatibility. The M4 cylinder has an alignment feature and shoulder at the rear of the cylinder which centres it in it's receiver and fixes it's orientation. The MP5 cylinder does not have this shoulder or the same alignment feature. There is also much heavier cutouts close to the piston window to clear other gears in the MP5 gearbox which sit higher than on the M4 PTW.
Side view of lower receiver
Two single conductor connectors connect the lower to electronics in the upper. Individually these connectors can pass through a restricted opening in the upper. To prevent connecting them backwards, they swap male-female ends.
You can see the hole in the sector for the optical gate turned up and out of the gearbox.
Shot into the mag well
It was hard to get light in here so I could photo the features that engage the magazine. Look like the same magazine engaging features as on the M4 PTW. Two machined fingers spread retention fingers on the mag. This isn't exactly a fitment tolerant means of releasing bbs from the mag. The TM style downpipe drops 3 bbs, but it's got a lot more slop tolerance than a M4 PTW which suffers from some feeding related issues caused by mag-hop up engagement technique. In the M4, this is exacerbated by having the mag latch so far from the engagement features (about 2" apart). At least on the MP5, the latch is very close to the engagement zone so the latch more positively pushes the mag against the engagement features on the hopup.
I'm disappointed to see the same hop up design as on the M4. The design is fussy and not very consistent. You can't adjust hopup with a mag breeched so have to keep popping the mag back out to make adjustments.
Upper receiver and front end
Man this is a nice assembly. I didn't get to take it apart (sigh), but when assembled it's very solid. No silly flexion. It has a stiff press fit to the lower and foregrip which makes disassembly a little difficult, but results in a very solid fitment when it's all together. No creaks of wiggles. The stock is aggressively pressed on. Even with the retention pin removed, pulling it off is a bit of a nerve wracking chore because you're expecting it to fly off and eviscerate some electronics. Luckily this isn't so. The stock comes off stiffly, but the wires inside are long enough that they don't whip tight and pull on strain reliefs. I figure the two electrical connections to the lower would probably disconnect if you yanked on them which is a nice failsafe.
Overall, this is a tremendously solid feeling gun! A pair of Europeans real steel MP5 manufacturers happened to come by while I was stripping the SystemA MP5. Talk about nervous. I was taking apart Kumi's only MP5 in front of Kumi and a pair of real steel makers. Luckily there were no spare parts on reassembly. It was funny watching them shoulder Kumi's PTW and comment excitedly. They were enthusiastic about the solid feel of SystemA's replica. I haven't got enough experience comparing the two. Too bad they didn't bring one of their guns over to compare side by side.
Specific overall comments:
-very solid build (you could probably practice face breaking with this)
-nice feeling heavy mags (aesthetics, but still nice)
-selector has solid engagement at any setting. You have to push a little hard, but it snaps into settings very positively
-Oh boy! A MP5 which can do the HK slap!
-logical takedown (I didn't run into any confusing dead ends, modular upper, lower, stock, front end)
-sexy demi glace finish *patissier kisses fingers* Very nice black semi gloss finish that seems very hard. Foregrip and stock were sandblasted for a matte sharp grippy surface
Thanks to Kumi for trusting me to not screw up a very expensive and important prototype!
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