This is a simple fix that most anyone can do without much knowledge of airsoft guns. For this example I'm going to use an APS M4 but it will work the same on any single piece hopup unit and can be applied to other guns beyond M4's. Really it depends on how the hopup is pushed against the gearbox, if it uses a spring like most do then it should be possible to do this technique.

Base gun


Things you need: Really all you need to do this mod is a couple small oring's that will fit snugly over the inner barrel that aren't so big that they stop the assembly from going together. As well you might need some minor tools to get to the hopup on your particular gun, since this is a general guide I'm going to assume you know how to tear apart your own gun to the point you can access the hopup chamber and inner barrel.

Oring's and Hopup/inner barrel


Problem: On certain magazines the feed tube is further forward or backward which causes the hopup to move forward which creates an air leak between the nozzle and hopup bucking. The stock solution to this is a small spring about the size of a bic pen spring to push the hopup against the gearbox. The problem is the magazine is long and has allot of leverage which means sometimes moving the magazine will cause serious drops in FPS and consistency.

Hopup Unit pressed firmly against gearbox


Solution: So someone out there(not me) thought about using an oring as a shim more less to push the inner barrel against the outer barrel thereby pushing the hopup chamber back against the gearbox with more force. This gives you more consistent pressure, eliminates that movement or most of it that can cause a problem. I've seen this problem to varying degree's on allot of guns, recently I saw an SR25 that was a 500fps gun consistently shooting 400 or so FPS. Took a quick look and noticed it was just using a spring, added a couple orings and back to 500fps consistently. So this can be a huge compression leak that is fairly hard to find but simple to solve. I forgot to mention when typing this. This particular gun uses two orings to get the right amount of pressure. Other guns might need more or less, the key is getting gentle pressure holding the hopup chamber against the gearbox as mentioned. But two orings may be just right or not depending on the gun. I've got several that use more or less based on how sloppy the QC is, as well as brand and model. So don't just toss two one because I said so;) Make sure when assembling the upper on the lower that it's putting a snug pressure and looks like the picture of the pin hole below with a little overlap but not much.

Here you can see the step that the oring will apply pressure against.


Hopup unit with orings put on the outer barrel, you can remove the spring or leave it doesn't matter.


Hopup unit back installed in the upper.


Upper and lower back together, note there is a little step of distance the upper will have to go further back onto the lower to insert the pin. That's about right in my opinion, just enough give it doesn't take allot of force to put them together maybe 5-10lbs max.


Downsides: Really I don't see any downside to this, when shimming the hopup to the gearbox you don't want too much pressure. You want it snug, so when you slide the upper back in place you need to apply a little pressure to the upper to install the front assembly pin. The upside of this mod as well is the extra pressure on the front pin will make sure it's not going to fall out on it's own if your gun is a little sloppy.

I'm sure there are plenty of guys out there familiar with this technique, and are using it. But there might be some guys out there that haven't seen it or don't use it. In my experience there is little reason not to do this, and it can solve allot of consistency problems when it comes to the hopup/nozzle airseal.

Take care!

Luke

EDIT: Added information about how many orings to use.

EDIT: Well guys I've had some success many hours into today fiddling with this project. I've tried around 10 different high caps at random in this gun, all sorts of brands I've got allot of them from TM, CA, to newer stuff. Either way on a whim I tried an old Star 30 round low cap, and the dang thing fed consistently and fps was +-2. It was a smidge low around 403 where I was seeing some 430's but it's 100% consistent. So I dug around tried some other mid caps and found another original generation G&P midcap that feeds and is 100% as well. So I have some sort of mag related issue that doesn't make a bit of sense to me. These same mags just for reference feed in every other M4 gun I've got around without any issues and they run the gamut brand wise as well.

So rather than my long question below which I'll leave there in case it might help someone seeing my issue in full and having any ideas. So now I'm curious to guys that have dug into mag compatibility problems and their solutions. What is actually causing the issues, is the hopup not pressing the release on the mag fully, too much pressure too little? Just curious what you guys have found, this is honestly the first time I've had mag issues with any of my m4's over the years. I used to only run TM mags so that could be part of it, but I'm wondering if anyone else has dug into it. I'm curious at this point but I'd also like to be able to correct this issue so I can use any of my mags as well.

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Well guys I've been working on a project for a while now basically a DMR M16 built from bits and pieces. I got a bunch of random parts and threw it together but I've been having problems and honestly I'm out of ideas of what could be causing this issue at this point.

So first I'll describe what it's doing. Random feeds probably feeds BB's 9 out of 10 shots maybe a bit higher but FPS is down in the 100-200 range most of the time with an occasional full speed BB at around 420fps with .25's. Hopup of course is all over the place because the velocity is all over.

Parts, metal body upper and lower don't know the brand but the fit together is fine, same goes for stock, and outer barrel. I've got a G&G plastic hopup chamber I was trying to get to work but once these problems started I suspected the hopup unit was the cause so I went ahead and bought a ZCI unit, but the issue still is there. I've tried several different buckings, several hopup chambers and same basic results. A few buckings gave me more misfeeds but I think it was how tight the lips were for feeding. I wasn't sure what nozzle came with the gearbox I picked up used so I thought despite the specs being on length wise I'd replace it also with a ZCI nozzle since it would match the hopup unit hoping for good results. Same thing. I did put an M140 spring in here along with an upgraded motor, cycle rate is good but I don't think it's fast enough to cause any issues, especially with that heavy of a spring. I replaced the tappet plate with a new SHS tappet plate. The other one I had was slightly too thick causing some issues or I thought. After thinning and fighting with the old one I decided it might not have been putting enough forward pressure on the nozzle to feed properly and seal but the same issue was still there. Spring on the tappet seems to be strong doesn't seem any different than any other version 2 boxes I've had apart over the years. Tried several barrels with the same results. I forgot to mention above the hopup unit is shimmed with orings to the geabox and it's got a fair amount of pressure against the box and should have a good seal.

So I'm looking for suggestions, I've been reading and racking my brain trying to come up with possible causes and honestly thought I had it on the run today with the new nozzle and hopup unit, but alas same issues again. So ideas would be more than appreciated, particularly if you've seen this issue or something like it and other things I can try.

Take care!

Luke

Hey guys in the background of the site mods/admins have often talked over things we've thought about adding or doing differently over the years. I wanted to see if any other guys had ideas or suggestions of things you think we as a group should be either doing differently or something we're not doing now that we should be doing. This isn't directly the site, IE add this feature or that. More so just MIA as a whole.

Those of you who know me I've only been back a short time, but I've been involved in MIA for a long time now. And I've seen allot of trends come and go, as well as members come and go over the years. I know allot of folks these days believe there isn't as much of a place for forums in light of the expansion of people using facebook and other alternatives. I personally don't agree with that, not that Facebook isn't a good place to share some information etc, but it's got some serious shortcomings especially when it comes to going back and finding information that has been previously posted. Also without organization and categorization it makes something as diverse a topic as airsoft very difficult to dig through information to find what your looking for.

Either way I just wanted to post a quick thread and see if there were any suggestions from the community that would help us all make a better community going forward.

Take care!

Luke

Well guys I went ahead and enabled a "like" system. So under posts now you can click "like" if you like a post. I didn't have a ton of time today to test things and find any bugs yet so post them in off topic in the bug reporting thread if you see them. I do know the default MIA style theme there are some bugs with the text at the top for "like stats" etc, I'm planning on plugging those here as soon as I have some time. On the "cake" digital theme things appear to render properly. So if the text instead of image label at the top bothers you switch to the cake theme for the time being and I'll get it fixed and update this thread once I get it done.

Take care!

Luke

Oh and I forgot haven't checked but I highly doubt this will function through Tapatalk only through the web view, doubt there is much I can do about that since Tapatalk is their own system.

Well guys I'm hunting for some small parts to finish building out a gun out of my piles of parts. I realized as I started putting things together that I'm going to need a few things that someone out there likely has lying in a box somewhere and wants to get a couple bucks for;)

Looking for:

*M4/M16 Mag catch/release along with spring, button and screw
*M4/M16 grip plate, or grip and plate. But I've got several grips and no motor height adjustment plates around

Now on another project I've had sitting, I need some AK bits as well.
*AK Selector switch along with hardware
*AK Lower receiver for full stock, and possibly the stock. Can be plastic on both, must be TM compatible.

I think that's it, price wise will depend on the part etc, but most of this stuff is cheap little bits bar a few. But generally I figured I'd could raid someone's excess junk and give them a few bucks for the privilege;)

Take care!

Luke

Edited to remove items.

Hey guys I had updated the youtube plugin to function the other day, but I didn't like the way it was working(and I apparently wasn't alone;) So I asked around and installed a different plugin. Now all you have to do is post the link to the video and it will embed in the message automatically and it works with Tapatalk as well.

Any trouble or questions just give me a shout.

Luke

Guys if you notice you don't have mod status say on a sub forum that you did have before just shoot me a note and I'll fix it. We've gone through and done most of them at least with who is active still but I'm sure there are some that I missed here and there so if you notice your missing your mod status in some portion of the forum you had before I can fix it for ya.

Take care!

Luke

Well guys normally I don't post much for reviews etc and this will be a short one but I had a less than stellar experience and I figured it might save someone else the money as well as headaches. I've heard allot of bad things about angel's custom products around the web on other forums. But recently I needed a spring for my sniper rifle and I figured hey I've got another Evike order why not put a spring on there as well and save shipping. So I looked around and the only option in an SP170 available was the Angel's custom. I figured why not I'll give it a try.

Installed the spring and it went well shooting 530fps on the chrono which is a touch low but with the short barrel on my TM VSR10 G-Spec I was willing to say it was likely just too short to get full velocity. Range was good, I was actually able to reach a bit further than my SP150 I had before in this gun with it setup as it is I could fairly consistently hit a 55 gallon drum at 100+ yards best was 120 yards. Previously I was having a very hard time carrying BB's past 80 yards or so with the SP150.

Fast forward 3 weeks or so and around 500 rounds, I noticed the bolt throw was getting much easier. I also noticed that my range seemed to be dropping off. Since most of my practice target shooting is at 75 yards I didn't noticed a change in accuracy really or range but I did notice my trajectory was changing as well as my hold over slightly. Well today I decided to do some longer range shooting and I was surprised I couldn't reach 100 yards. So I walked in and around 80 yards I could hit again, which made me wonder what FPS it was actually shooting and if I was right that the spring was loosing allot of strength fast.

Well I tossed it on the chrono and instead of the 530 I had, I'm running 400fps. Nothing has changed compression wise, and I haven't done it yet but I'm planning on tossing my SP150 back in until I get another spring in hand but I expect it will jump right back to where it was before I put in the SP170. But the basic results are the spring got weak enough in less than 500 rounds to drop the FPS 130 or so lower than where it started which in my mind makes it garbage. I'd read that same result elsewhere but really wasn't sure if I trusted it, should have listened.

Also called Evike and explained the situation since it's been nearly exactly a month since I placed the order only a few weeks since I got the spring and was basically told that springs are not under any sort of warranty and basically I'm out. I understand the theory here, and that they probably get allot of guys trying to replace parts that aren't bad. But I gotta feel that was a negative knock against them as well. Which is unfortunate since I've been pretty happy with Evike and have ordered quite a bit from them over the last 5 months or so.

All in all it is what it is, I won't be buying anything else with Angel's custom on the package that is for certain and I'd probably recommend other guys do the same, just too many reports of the parts not being worth the price at all.

Take care!

Luke