Hi all,
I have taken apart the SOPMOD and am trying to rep[lace some parts but I am unsure how to take the piston head and spring apart. The piston head has a very small hole, but that's it. Do I need to drill it out to access a screw? Once I have removed that will I be able to remove the spring?
I have way too many pieces of SOPMOD on my table, sure hope I can rebuild it
Ok I don't own a SOPMOD but I'm guessing they are generic Marui parts which means the Piston and Piston head are bonded together along with the spring. Basically you are going to need to upgrade the Piston, Piston Head and Spring.
I was under the impression that there isn't yet an aftermarket piston available, just a piston head...which would make me think they are swappable? I can pick up a spring if I need one, but I am not sure about the piston.
Assuming you have bought the laylax piston head replacement, here's how to install it :
On the surface of the original piston head you should be able to see a ring seam in the center. That is a glued-on cap which once pried open (destroys original piston head) you will have access to a screw. Remove the screw to free the spring and spacer from inside the piston. You can reuse the piston. To reuse the spring, you will need to cut off the part that protrudes from the piston facing end so that it can sit flush inside the piston. (resting against the spacer in the piston)
G'luck!
In the SOPMOD disassembly thread Q said...
"So I picked up a Prometheus Piston head. You cannot use the ball bearings/spacers but just the piston head, the screw, and the black plastic screw collar. It's the screw and the screw collar that pushes that brass rod of the blowback engine. Will see how durable it goes."
Was that for the old Piston head? The one I bought is for the M4 Sopmod (ver 2) so I am assuming it is OK to use the spacers and bearings?
Thanks Anarchy
Aargh!
So my SOPMOD upgrades are giving me nothing but stress.
When I first bought my SOPMOD a few weeks ago it powered in at 91m/s. I decided that I wanted to use this as an outdoor skirmish weapon, and misunderstanding some advice about longer barrels improving power I bought a 550mm barrel.
When I installed it I immediately lost about 10 m/s, and tested in at about 80m/s
Yesterday my Chrono came (initial 2 tests were done at stores) and I tested both with the long barrel and the stock, and the stock barrel was up over 90 again.
Having bought other upgrade parts I opened it up this afternoon and this evening and spent about 6 or 7 hours installing a new piston head, cylinder (type B), cylinder head, and nozzle. I figured with these 4 upgrades I should be able to gain a few m/s and get as close to the limit as possible. Unfortunately I ended up going backwards, and am instead now at 86 m/s. All this time, money, and frustration and it went backwards! I am so disappointed.
Any ideas as to what my next step should be? Do i open it again and try to put back some stock parts (the piston head is dead)...or should I just forget about ever getting it stronger. A new spring maybe. I don't know what I did wrong. Surely these extra parts should have contributed in some way?
Have you tested the range? FPS is not the be all and end all of the equation! Other factors maybe in play now, such as range, more back spin much higher accuracy and so on.
Welcome to the world of modding dstole, you're gonna need to squish a few lemons to get to the cheesecake. (or whatever the proverb is)
Few questions :
- Can you list the exact parts you replaced?
- Can you post a pic of your mechbox opened with the new parts installed?
- When you were testing was the hop on?
- Still quite shocked your gun chrono'd in at 91m/s stock, I've not seen anything higher than 84m/s stock. Can you also post a pic of the stock parts you replaced?
Break a few eggs to make an omelet I think is the actual term.
Update:
So things get more interesting...
Stock Inner Barrel before upgrades 91m/s
Stock Inner Barrel after upgrades 86m/s
550mm 6.03 barrel before upgrades 82m/s
550mm 6.03 barrel after upgrades 87m/s
So looks like the upgrades brought me down 6 m/s with the standard barrel but up 5 with the tight bore. Really trying to figure out how this all comes together
@FarEast > Haven't had a chance to test outdoors so not sure about hop etc. Will test when I have a chance.
@Anarchy > Yes, Daniel was very surprised when we tested it that Saturday as he had made changes to his and I was a good 5m/s more than him stock.
The exact parts that I have changed at this point are
1. Laylax POM Piston Head Ver.2 for Sopmod
2. Laylax Sopmod Sealing Nozzle
3.Laylax Aero Cylinder Head
4. Laylax Cylinder B(which doesn't look like the picture, it has ports cut at the very end, not mid-way like the photo.
5. Laylax Soft Hop-Up Bucking
6. Laylax 6.03 tight bore barrel (550mm)
I didn't take any pictures at the time, but I will open it again to try and make some small changes again soon, and will take photos then. I think the 2 main issues might be the cylinder and the fact that it is ported and I think the B type is made for a 420-400 barrel so mine is to long, and the inner barrel is too long. I have ordered a SystemA M85 Spring and am thinking of putting that in as well to see what happens, and then will start mixing and matching. I think I will get a non-ported cylinder or a shorter barrel to see if that helps.
My apologies to the board for venting the other night. I had literally spent 8 hours doing my first take apart and rebuild. When I put it all back together and pulled the trigger there was nothing! I was so gutted...I seriously felt ill
But it turned out that one of the wires didn't connect back to the motor properly. OK, ready, upgrades done, it's gonna be awesome...and -5m/s...I am sure many of you can imagine.
Spirits are renewed though and I am looking for other ideas/suggestions/etc.
Oh, and my wife now thinks I am a geek and my son has upgraded my "cool dad" status...he wants me to do upgrades on his "Boys MP5"
Is there anything I should know about replacing the spring? The one in there now is the stock one that I had to cut after I replaced the cylinder head. Is it just a matter of dropping it in?
Well, mine shot at 92~94 when it was brand new, after replacing the inner barrel with a 407 mm one.
Anyway, here's my take on your problem:
Your cylinder is too small for an inner barrel of 550 mm. If it has cuts at the end that is a Type B cylinder. Try putting back the stock cylinder and see how it goes. If it still comes up short, try getting a spring guide for new version 2. That will give you a bit more power. But I advise you to check first if the stock spring (with the protruding part cut) is as long as a Laylax spring for version 9. If it's longer a lockup might occur when you put a new spring guide.
For comparison, the parts in my gun are:
Laylax Cylinder Head
Laylax Air Nozzle
Laylax Cylinder (type D)
Stock barrel cut to 280 mm (CQB-R length)
KM/Head 1950 Piston head
Stock spring and spacer/nut
This setup yielded 94 m/s in SEALs last Sunday.
I also bought a few mech parts, mabe we can hook up again for specific SOPMOD work...
@ Hazard > Thanks that is what I suspected. For future reference, which is the Laylax cylinder that isn't ported? The pictures on their website all look the same.
@ Hawk > Sure. I am probably going to get on it this Saturday as Sunday is Father's Day. Do you want to come over again? We should start early as it take a while. I will remove the ported cylinder and put the stock one back on as well as replace the spring with a SystemA M85. I will try the spring first though, then I might not have to take it entirely apart again...although maybe I should just to make sure all is well and to lock things down with some locktight (or whatever that stuff is called). What are you planning on doing Hawk?
Another Question
How tight should the stock pipe be? When I replaced it a stopped tightening it as soon as it started to get real snug, and then loosened it off half a turn to line up the battery wires. When I put the buffer and stock ring back on there seemed to be more threads visible then when I started, but the wires fit almost perfectly. Is there any chance that the stock pipe could be loose and this isn't putting enough pressure on the spring, hence a loss in power? Not entirely sure yet how the spring/blow back/piston all interact so forgive me if that is a dumb question
When re-attaching the stock pipe will it naturally stop or is there the potentially to over tighten?