[bobcat]

First, I don't know where to put this thread. Please move it!

So after much frustration with making a nub and attempting to perfect my M700's hop up, I decided that going a different route may be a better option. I recently caught wind from another member about ER-Hopping the gun would help greatly with accuracy and the such. After pricing everything and consulting HS5, I decided I am going to send my stuff to Skag to have him help me out with the ER-Hop. I know that there are a few members here with KJW M700s who are somewhat in need of a better hop-up system so I decided to venture into the unorthodox ways in hopes to find the best system for this rifle. And so we begin...
Last Tuesday I purchased the beginning parts:

First I purchased a PDI raven barrel. Why? Because I was sick of my Angel Custom barrel and I just so happened to have a $75 credit at Amped Airsoft from the white .43s I ordered. Also with that credit I purchased a Prometheus soft bucking.
Next I went to Air Rattle and got myself an IER-Hop patch. IER because I live in an area where the summer and winter are polar opposites and I plan to use the gun year round.
Next I went over to shape ways.com and ordered the Hunterseeker5 ER hop chamber for the M700. This is needed because of the extended hop up window, which requires a larger EM-Nub (which shall be provided by Skag). Shapeways will take around 10 days to complete the print, and they estimated May 29 that I will get my part.

So in short, heres what I ordered:
1) PDI Raven Barrel
2) Prometheus Purple AEG soft bucking
3) IER-Patch
4) HS5 Chamber for ER-Hop in KJW M700

Next portion is to get everything in, package it up, and send it to Skag to mill the barrel and install the patch.
I'll try to keep everyone updated on the build here. I remember the last thread about KJWs and ER-Hops was more of a question thread, so here I'll be actually updating you on the progress of a build. If all goes well, this thread will end with a shooting test, which will hopefully push the limits of the gun. Stay tuned!

 

[bobcat]

Alright so today we get a very simple update.

All parts have been shipped! Turns out Shapeways had prebuilt a model of the chamber I ordered so I don't have to wait a week for it to print. Yay!
Today the IER-Hop patch arrived. It's a nice blue color.

The PDI barrel and Prometheus bucking have been transferred to my local Post Office. If I get home from school tomorrow and the package is still not there, I'll just drive over and pick it up.

 

[bobcat]

New update…

PDI Raven Barrel and Prometheus Soft Bucking arrived today.
Turns out that Shapeways had a model of the chamber already printed. So instead of arriving May 30, it'll come to my doorstep tomorrow.

With that said, tomorrow I will receive a quote from Skag for his services. I may have this little project done by next week.

 

[bobcat]

Sorry for being so lazy in this thread… Seems like no one is interested. But a promise is a promise and I will update once again.

Since the last update, I got the shapeways chamber. The chamber for some reason did not come with the C-Clip, which is very necessary for keeping the barrel in the chamber. Shapeways sent me a whole new chamber (arrived yesterday), which is why I delayed until now for the update.
With everything here, I sent the package to Tony Zito, the HS5 certified ER-Hop technician.
Things should arrive to him on Thursday this week, hopefully I'll have everything back before my local skirmish on the 21st. If I don't, that whole hide goes to waste. I asked Tony to use priority mail and not delay with the project.
I also sent him my outer barrel so he can even the cut on it.
Photos later

 

[bobcat]

Thats for the input guys

 

[bobcat]

Ok, thanks guys.
Maybe at some point when everything is done I'll make a final "build thread" so I can tie all of the previous project threads together.

 

[bobcat]

Well, I am thoroughly disappointed.

Yesterday, my maximum range was 200 feet with a .43g bb, shooting in the vicinity of 450 FPS. Not sure why 200 feet was as far as it was going, but I continued to shoot.
Those shots would over hop, under hop, then rarely curve to the left.
Near the end of the day bbs stopped going 200 feet. That became a pipe dream, because now the gun was shooting a mere 10 feet. Yes, 10 feet.
I hand tested the barrel seal and found that the barrel could freely move within the bucking because the chamber only holds it in via friction, what fun. I pushed the barrel closer to the chamber, it became all sealed up.
Shot it again, first shot flies…11 feet! QUE BUENO! The next few shots, well, some didn't even come out the barrel. It became obvious that I was losing massive amounts of my CO2 somewhere between the barrel, patch, bucking, chamber, nozzle, bolt, and magazine.
I began my autopsy in that order, reversed. I noticed to issues with the magazine, bolt, or the nozzle when hand tested. My investigation continued onto the chamber. The first thing I notice is a small piece of rubber sticking up from the bottom, the first sign of a ruptured bucking. I decide to bypass the surgical removal of the chamber and went straight to the bucking and barrel. My diagnosis concludes as so: The barrel shows that the ER-patch had torn in half and the bucking was torn near the nozzle end.
Not only was the patch torn in half, but it looked like a dog ate it, crapped it out in the mud and let it sit while getting run over by ATVs. The patch, needless to say, was in very bad condition. What happened? I have no clue.
Tony Zito and I exchanged several emails prior to the findings, starting with very easy suggestions, like barrel spacers. Yeah, those will increase the range by 190 feet. Easily. He eventually told me just to check the bucking and stuff and report back, I had already done that when I received the email, I'm anyone looking to fix a rifle would have done that anyway.

All in all, I am VERY DISAPPOINTED with everything. Lets begin with this: I spent more than $200 on the project. Thats $50 in parts and $160 in services from Tony Zito. On the second day of shooting, everything explodes. I'm telling you, if a KJW M700 had an appendix, it clearly ruptured. What does the surgeon do when the appendix has already ruptured? They clean it up and hope the patient lives. That is what I am going to do.
I'll clear this up with Tony and the mess from my gun, and hope that the gun lives.
Thanks for following this project, to whomever actually did, it's over now. I do NOT recommend this. At All.

So what am I going to do, I'm out a good amount of money and I've got a small skirmish tomorrow. I replaced the internals with everything old. Angel Custom barrel, stock rubber, stock chamber, stock nub. Performed better.

 

[bobcat]

To tell you the truth, I have no clue what it was. Even when I don't have experience, I can usually come up with a possible solution other than what you mentioned, but this time I am drawing a blank.
I can give you this, though: Tony did say that the chamber was a tight fit, but I don't think it would have been tight enough to tear a patch after 100 shots.
The ER-hop filing job seems pretty good, though it does look like Tony did a slight downward slope towards the end of the barrel on the window.
I'll post pictures in a bit

 

[bobcat]

Plaz, that seems like a relatively good theory, it makes some logical sense.
The FPS was around 450 using a .43g bb. I don't personally own a chronograph or live near one so I am using a rough estimate based on my pressure gauge, which is of course broken, that showed 200 PSI (it shows roughly 70 PSI greater than true reading)

The IER-Hop was designed for high speed, heavy weight bbs, right?
Also, when I took out the barrel, the patch looked, in no way, glued in place. It freely fell out of the barrel.
I emailed Tony Zito earlier today with no avail as well

Might be a direction to take your M700 if it works.

Keep me posted on that. I'm really close to calling it quits with my KJW M700, I've spent a lot of time and money, not to mention the blood, sweat, and tears (quite literally) I've put into this gun (and cleaned off of the gun, too) I mean, I think its hit around $300 in just the hop-up, I still can't find a solution!

Plazmaburn: I guess it's safe to say, I'm counting on you for the nub design. I've tried a lot of things, and still nothing.

This much work and little play makes this bobcat sad.

@desertsniper, I am currently using the stock setup as a place holder. Skirmish tomorrow, lets see how it goes. Terribly, well, sucks for me. I've run out of ideas with this rifle.

 

[bobcat]

Tony seems to agree to redo the install, he's baffled about the situation. He said he's never seen something that beat up.
Again, this is from 140 PSI with .43 bbs, on a 455mm barrel.

 

[bobcat]

Update time… sort of.

Its been a week… I have still not gotten an official, "Yes, I will redo the install." I have only gotten small hints…

Since my last post, Tony has been 100% unresponsive to my emails. Even prior to that, he only answered emails as to why it could have done that, nothing to do with sending it back.

Everybody I know thinks I'm crazy because my KJW M700 curves left and right, which is apparently "alright, even if its a sniper rifle"

 

[bobcat]

I'm giving Tony until tomorrow before I call him for a 1-on-1 talk over the phone.

I did see your posts on the Mantis, I followed that all the way. You were using .66g bbs, which contributed to the awesome ranges. I also noticed you said that accuracy was not perfected yet. What do you plan to do about that?
Do you think that the ER-Hop was giving the bb too much friction therefore reducing its velocity and range? Not going past 200 feet seems odd for a system like that. As I recall, you are using a simple R-hop design?

 

[bobcat]

Whats actually funny…
I can safely conclude that range, prior to the ER-hop, was never an issue. I've got a 500-foot pond in my backyard, and 300-foot natural range, the bbs have always flown 300-400 feet without issue, but sometimes over-hopping. It has always been the accuracy that has been sub-par.

Last night I got really determined and decided to do something that I have never attempted before, and that is a flat-hop. I've got a bunch of stock parts from the KJW, I've owned several. I didn't want to hurt the fragile setup I have now because it didn't curve (but has inconsistent hop) so I decided to use stock everything. This means the stock plastic chamber, stock brass barrel, stock nub, and the stock bucking flat-hopped. Being my first time flat-hopping a bucking, I did a sub-par job, hell I probably double-bogied it… prior to installation I did notice a little piece was hanging out on the left, so instead of fixing it my lazy self decided to let it be and assume there would be left curve.

I can finally say I am thoroughly impressed with the performance. I mean, shooting 230 feet accurately was a pipe dream before… And yes, I was correct about the leftward curve, my fault entirely.

But there is one thing that has bothered me since I shot the rifle and hour ago: I'm using a stock barrel with a 6.10 bore, and who knows how good the quality control is on that. Why has this bothered me? I never feel satisfied until I know why something happens the way it does. Popular belief has it that stock barrels are bad for accuracy no matter what… I've been thinking about the theory behind using wide-bores for polar star rifles, do you think this could be the answer? I could use some input here…

 

[bobcat]

It just ticked me off that I spent $200 with the only HS5 Certified tech to ER-hop my barrel. The tech wanted to charge me another $15-20 just to have it reinstalled, plus two way freight charges along polar ends of the coast.
Considering Tony is the only HS5 certified R-hop tech, I'm sure you're right, Vanevery. I don't know what kind of test setup he had.
I will tell you I was surprised to hear he finished the job literally overnight… (Shipped Tuesday, arrived Thursday, done by Friday, shipped back Monday, arrived Wednesday)

Because I still have the ER-Hop products (chamber, barrel, nub, etc.) I was planning on going to McMaster for the tubing, not making the mistake of spending $21 on two patches, then having Tony take the extra… And trying to reinstall the patch. If it breaks, hey, I got 10+ feet of it…

Thanks for the input, Vanevery

 

[bobcat]

Truth be told, I don't like HS5 either… They over charge way too much.

Paid Tony Zito of HS5 $160 to do an "excruciatingly difficult" ER-Hop, and an extra like $30 because it was a steel barrel…
Later that month I spent ten minutes with a metal file, vice and another steel barrel, did an ER-hop cut just fine… it made me angry

As for your offer, That is just awesome. I cannot believe how nice people are on this forum; I've gotten several offers from other members here about this thread, its just fantastic.

I'll have to consider the offer, basically its either I give it a go myself or I send it to you… Maybe I can attempt an R-Hop on my other barrels… (AKA, leaning towards having you do it…)
Do you have the material available, or will I have to supply?

Thanks again!