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Frat
05-07-2006, 04:57 PM
Been playing around with using HPA and doing a low pressure sort of mod on the MR1 I have installed a delrin bolt, polished the internals and installed a regulator. When I tested it out his morning I was getting 285FPS at 300 PSI. I am having some intermitant cocking issues that I believe is gas related. I am still using the stock valve. I have a magnaport but I had to order some cupseals from Lapco. Nothing I could do could make the Magnaport valve stop leaking air. I have a low mass striker comming and between the valve and striker I am hoping to get it down to around 200 PSI

ooglieboogliebob
05-07-2006, 06:05 PM
... umm... your probably gonna need a spring kit ... heavy valve spring and light mainspring ... the stock mainspring might be hard for it to recock ...

Frat
05-07-2006, 10:38 PM
umm... your probably gonna need a spring kit ... heavy valve spring and light mainspring ... the stock mainspring might be hard for it to recock ...

Ahhh forgot to mention that. Already have it and have been playing around with it. Right now I am running heavy main and light vavle to keep the valve open longer. Something that would be nice is if one of the manufacturers out there would make a LPC for the MR1.

DRAGON
05-08-2006, 01:10 AM
..........I have a low mass striker comming and between the valve and striker I am hoping to get it down to around 200 PSI

What you don't know will hurt you. You don't seem to know that taking the pressure down as far as possible is not your goal. Finding the mean of pressure, velocity and efficiency is. Expect your pressure to esculate once you install a very light striker. Not sure about this because all you did was generalize and gave no specifics. A secret huh? -

Far as the leak prob, put the stock valve pin, cup seal and cup seal guide in and the leak should cease. You should get a relatively decent pressure from that till your Lapco is delivered -

druid
05-08-2006, 01:30 AM
the intermittant cocking issues are because the marker's starving for air. until you get a high-flow valve in there, it will. Also, you didn't say what delrin bolt you are using. If it's an ACS bolt, sell it and get one like a sunbear (eaglelox on this forum) with O-rings...

Sunbear bolt Here (http://insanepainsports.com/page2.html)
review on PB Review (http://www.pbreview.com/products/reviews/3629/)
review of Nightstriker XL (http://www.pbreview.com/products/reviews/3620/).
With the MR series, I doubt that you would feel the air rushing past a delrin bolt... You need to seal the bolt chamber to get greater psi in the chamber, as well as the striker tube. I used ^^Eagle's products with huge success and highly recomend them.
If that new striker you ordered doesn't work out, get a Nightstriker or go to Otter's site and look up the "dish" mod...should be in Project LP...

Frat
05-08-2006, 09:09 AM
http://i19.photobucket.com/albums/b170/lhofeld/MR1002.jpg

What you don't know will hurt you. You don't seem to know that taking the pressure down as far as possible is not your goal. Finding the mean of pressure, velocity and efficiency is. Expect your pressure to esculate once you install a very light striker. Not sure about this because all you did was generalize and gave no specifics. A secret huh? -

I did not mean to be secretive just tired when i wrote the post last night. Here is what I have done so far.

Delrin bolt from Alamo City. I have also ordered one of their strikers. I ordered the one with the orings and a feature I like about it is the air passage going from the valve port to the bore is cut at a radius. This should offer a smoother transition.
http://www.alamocitypb.com/manufactpages/kingman.html

Magnaport valve Ebay

Aim Shock regulator Ebay

Lapco bottom line adapter block, Vertical ASA adapter and cup seals.
http://lapco.net/prod/accessories/spy_accessories.html

OK my understanding of LP is that you are trading volume for pressure which is why the high flow and low mass components are required. When I install the new striker and get the magnaport valve to work I expect to drop down to a medium main spring. Right now the gun is set up with a heavy main and a light valve. With the magnaport, light striker and lower pressure there should not be a problem with getting the valve open and getting air through the marker. I am going on what I have read and my understanding of how the marker works and air flows through it. I would like to see if I can get it down to 200PSI and see if it will still function. I am happy to have it working below 400PSI but I am curious to see exactly what I can squeeze out of it. I am going to get a T board with a bounce beam eye set up. I have found with the E trigger installed that you can shoot faster than the gun can feed. I never chopped a ball with the mechanical set up but I have cut quite a few with the E-trigger. I thought at first it was the new bolt but when I put the stock bolt back in it was doing the same thing.

DRAGON
05-08-2006, 10:52 AM
OK you got some of it right and some not.

1) You cannot predict what the best spring combo will be. That's up to your marker and trial and error -

2) Depending on the weight of the striker, lighter means less dwell duration, less dwell duration means less flow to the barrel and striker, less flow to the barrel and striker means upping the pressure to achieve velocity and recocking. All depends on the weight of the striker -

3) The aformentioned depends on the volume put out by the reg as well -

4) You have no LPC on that setup therefore you have no excess volume reserve to feed the valve at high rof's -

If I were to do a project as such I would:

1) Use a bottom line reg -

2) Use a New Designz or Rocket valve -

3) Keep a modified heavy weight striker for a decent dwell -

4) Drill out the existing foregrip for volume and tap the bottom for an adapter for a line-in -

5) Add an e-frame -

Did you make that shoulder stock or buy it and adapt it yourself? Is it steel or aluminum? -

druid
05-08-2006, 10:56 AM
OK my understanding of LP is that you are trading volume for pressure which is why the high flow and low mass components are required. When I install the new striker and get the magnaport valve to work I expect to drop down to a medium main spring. Right now the gun is set up with a heavy main and a light valve. With the magnaport, light striker and lower pressure there should not be a problem with getting the valve open and getting air through the marker.
Provided that there are no air leaks in any other part of the marker
I am going on what I have read and my understanding of how the marker works and air flows through it. I would like to see if I can get it down to 200PSI and see if it will still function.
I doubt that it'll happen. I had an Esprit that I got to 200psi @ 279 (200psi@279) FPS but it required a significant amount of modifications to do it. The parts alone cost me $350 (and most were used parts).
I am happy to have it working below 400PSI but I am curious to see exactly what I can squeeze out of it.
Id suggest shooting for something around 350/375psi and be happy with that
I am going to get a T board with a bounce beam eye set up. I have found with the E trigger installed that you can shoot faster than the gun can feed. I never chopped a ball with the mechanical set up but I have cut quite a few with the E-trigger.
...and now you're going to make it worse...
I thought at first it was the new bolt but when I put the stock bolt back in it was doing the same thing.
It's because of the angle feed and a slow hopper.

Frat
05-08-2006, 11:39 AM
I am going to get a T board with a bounce beam eye set up. I have found with the E trigger installed that you can shoot faster than the gun can feed. I never chopped a ball with the mechanical set up but I have cut quite a few with the E-trigger.
...and now you're going to make it worse...
I thought at first it was the new bolt but when I put the stock bolt back in it was doing the same thing.
It's because of the angle feed and a slow hopper.

Actually I do not plan on shooting it on full auto or ramp it and realize that the angle feed slows the works down. I am using a Revy Tripod on the marker which can keep up with my pilot. For me I want the T board for the eye set up. I want to make sure the marker will fire only when a ball is present. I play in the woods and I do not need the to fire 36 balls a second. The stock is what came with the marker with the top rail removed. I cross drilled it and usa a quarter inch ball lock pin to retain it.

new_Faction64
05-08-2006, 12:44 PM
That cut off stock looks great man! Awesome idea! How's it perform?

DRAGON
05-08-2006, 03:04 PM
Did you make that shoulder stock or buy it and adapt it yourself? Is it steel or aluminum? -

Just noticed, you just cut the top part off the stock that came with it between postin last time and now lol. Well duh me :o Looks better than the stock version. Seems like it might make the marker bounce on your shoulder a little with the top peice cut out. I thought of something similar for the stock attachment point. I heard you have to unscrew the stock every time you put it away if you have a small case for it. I was thinking more in the line of a Cocker q-strip pin but I doubt it's long enough -

Frat
05-08-2006, 09:29 PM
The stock on the MR1 is really beefy. I was not sure how solid it would be but I was sure enough to try it out. The plug part that attaches to the gun is actually aluminum and goes back into the stock itself. With the top rail gone you can get your head in behind the gun and once I finds the sight I am looking for I will be able to use optics pretty well. It has a little flex to it but I think it shoulders nicely and it is more than strong enough. It appears to be glass filled resin and not just injection molded plastic. I laid out my cut lines and used a jig saw to rough cut it. I tried using a Dotco and a 180 grit sanding disc to finish it out but it wanted to melt so I ended up using sand paper and a file to finish it out. If you have access to a real shop a band saw or even better a mill will take more of the work out.

lilc
05-09-2006, 05:37 PM
http://i19.photobucket.com/albums/b170/lhofeld/MR1002.jpg
Gorgeous stock modification (and practical too)! Hope it doesn't break! :rolleyes:

Frat
05-09-2006, 09:27 PM
Hope it doesn't break!

Actually I am more concerned about the receiver but not much.

new_Faction64
05-10-2006, 12:44 PM
Frat, what's that thing sticking out of the rear of the gun, what's it for?

yamaha cow
05-10-2006, 01:05 PM
remoteline

new_Faction64
05-10-2006, 04:02 PM
remoteline

top rear, my bad, right behind where the bolt would be, but on the outside

Frat
05-10-2006, 09:54 PM
That is a ball lock pin that I use to hold the stock in place. It also doubles as a sling attachment point.

http://i19.photobucket.com/albums/b170/lhofeld/MR1003.jpg

yamaha cow
05-11-2006, 05:35 AM
cool

Frat
05-27-2006, 07:24 PM
Well after about 3 weeks of tinkering I have ended up with the following:

Regulator set @ 400PSI
Stock valve with magnaport pin and Lapco cup seal.
Medium main spring and medium valve spring.
polished stock striker and delrin bolt from ACP.
Velocity adjuster backed out and flush.

I had it operating at about 300 PSI but to get it to function right I had almost zero efficiencey. I kid you not I would get no more than 50 shots per 47CI tank. as soon as I tried to do anything that would up the efficiencey I was back to the cycle problems. I think part of the problem is a lack of a volumizer. All in all I am happy with it. I shot about a case through it today with zero malfunctions that were not operator induced. It is still very quiet but not whisper quiet as some of the guns.

yamaha cow
05-29-2006, 11:06 AM
do u have a link for that expansion chamber

kies
05-30-2006, 09:21 AM
hey frat , is that stock any good in the field?

Frat
05-31-2006, 08:18 AM
I bought the reg off ebay. It is an AIM Shock and seems to work very well. The stock works great and when I can find the scope I want theat doesn't require me to have it shipped from Hong Kong I am going to mount an Aim Point clone on it.