mcarterbrown.com  

Reply
 
Thread Tools Search this Thread
Old 03-12-2013, 04:26 PM   #11 (permalink)
Ole' Papa Pump
 
turbowagonman's Avatar
 
Join Date: Oct 2012
Location: Mentor, Ohio

Quote:
Originally Posted by surein View Post
IMHO Leave the valve spring as is and muck around with the hammer spring.
I agree, I spent a lot of time trying to spring tune my Sterling and I found the best results with just messing with the Hammer/Sear spring. I tried to mess with the valve spring but it made less consistent shots.

Thanks to this thread I think my gun is out of tune because I have to have the pressure so high (800 psi) to get 280 FPS, but with what James_Blond said about the main pump rod opened my eyes to think mine needs to be screwed out some because I need to have the Hammer/Sear spring so long (I cut a Spyder Spring) when I unscrew the front frame bolt the spring just pushes out the "pick up assembly" kind of violently. After all the gun hasn't been "timed" since I got it back in the 90's.

So it's back to spring tuning again.
__________________
Started with a Splatmaster, moved onto a Nelspot 007, then came the Autocockers, then a STERLING Pump, next was a Bob Long defiant then a PM7. As of now I have 5 Sterling Pumps, 1 Phantom for SC, a CM SS-25, Sovereign 3 and 2 Spyder's plus a bunch of extra parts.


Feedback:
http://www.mcarterbrown.com/forums/f...-feedback.html
turbowagonman is offline   Reply With Quote
Old 03-12-2013, 04:52 PM   #12 (permalink)
Active Member
 
surein's Avatar
 
Join Date: Apr 2011
Location: Toronto

Quote:
Originally Posted by turbowagonman View Post
..with what James_Blond said about the main pump rod opened my eyes to think mine needs to be screwed out some ..
Not sure about the old school Sterlings but the STPs come with the main rod glued to the pump arm. I personally have no idea how one can take this apart
__________________
_______________________________________
Feedback
surein is offline   Reply With Quote
Old 03-12-2013, 08:10 PM   #13 (permalink)
Ole' Papa Pump
 
turbowagonman's Avatar
 
Join Date: Oct 2012
Location: Mentor, Ohio

Quote:
Originally Posted by surein View Post
Not sure about the old school Sterlings but the STPs come with the main rod glued to the pump arm. I personally have no idea how one can take this apart
I have a Proline and mine screws into the Fore-Grip and the piece the sear catches on is threaded as well. That piece has a set screw and I set everything up to "tune" it but my first 5 shots were within 4 FPS, I couldn't bring myself to mess with it.
__________________
Started with a Splatmaster, moved onto a Nelspot 007, then came the Autocockers, then a STERLING Pump, next was a Bob Long defiant then a PM7. As of now I have 5 Sterling Pumps, 1 Phantom for SC, a CM SS-25, Sovereign 3 and 2 Spyder's plus a bunch of extra parts.


Feedback:
http://www.mcarterbrown.com/forums/f...-feedback.html
turbowagonman is offline   Reply With Quote
Old 03-12-2013, 11:37 PM   #14 (permalink)
Seasoned Member
 
Tinman's Avatar
 
Join Date: Aug 2010
Location: Brighton Michigan

I think that marathon has a brand new sterling, these come with very light hammer and valve springs. It is a completely different animal than a proline sterling, with adjustable velocity and all. for consistency arrow recommends 600-650 psi hpa
If he goes and drops a cut spider spring in it, it will do nothing positive for his marker or his pumpstroke.
__________________
Proud Delta Ops member
playing for the betterment of the game.
My Feedback

Last edited by Tinman; 03-12-2013 at 11:41 PM.
Tinman is offline   Reply With Quote
Old 03-13-2013, 01:35 PM   #15 (permalink)
MCB Member
 
Join Date: May 2008

Quote:
Originally Posted by Tinman View Post
I think that marathon has a brand new sterling, these come with very light hammer and valve springs. It is a completely different animal than a proline sterling, with adjustable velocity and all. for consistency arrow recommends 600-650 psi hpa
If he goes and drops a cut spider spring in it, it will do nothing positive for his marker or his pumpstroke.
Then his gun has changed little to none from my AP stp from 2000. It's why I suggested turning the pump rod (if able) otherwise you might have to adjust the pick on the end of the pump rod which either has set screw or is loctited in. I suggested moving the pump rod as it is the easiest to undo if you make something worse. Most likely he needs to fiddle with the input pressure and get his adjustable hammer tuned properly.
__________________
My MCB feedback: http://www.mcarterbrown.com/forums/f...ml#post2245661

For Sale: http://www.mcarterbrown.com/forums/m...ml#post3163559

wanted: cocker beaver tail, reg extender, black anno palmer reg in good shape, ANS 90 frame, mine rail that can be mounted backwards for more length (dovetail).
James_Blond is offline   Reply With Quote
Old 03-13-2013, 08:09 PM   #16 (permalink)
Seasoned Member
 
Tinman's Avatar
 
Join Date: Aug 2010
Location: Brighton Michigan

Ok, James I want to be sure we are talking about the same thing, there are 2 rods on the pump, one is the Pickup Rod the other is the Pump arm.

The pickup rod has two different thicknesses with a step in the middle of the shaft the thicker end being in the pump handle. because of the step in the middle of the shaft there is no benefit to changing the depth of this rod in the pump handle. The pickup rod will always enter the marker the same distance stopping at the step. This is where the stop nut (pickup collar)comes into play (large brass nut that the pickup arm slides through) by adjusting this nut you control the depth the pickup rod enters the marker.

When you change the pump arm position it only changes the position of the bolt.
unless you have it wound too far in and it impedes the pickup arm from being able to return all the way forwards. (causing trigger engagement issues)

In a pumping motion, The pickup on the bottom of the pickup rod compresses the spring and picks up the hammer and pulls it to the forwards position. ( If the pickup is too far forwards on the rod it may not grab the hammer, if it is wound too far out it will pickup the hammer but may not engage the sear properly )

I really don't want to argue the point that Springs have changed..But if i must, Hammers with the adjustable velocity nut are intended to have springs that are significantly lighter and shorter than Proline springs. Arrow has them listed as STP springs.
I ordered a handfull from Arrow for my Proline stp, it didn't work out. I cut spyder springs got it back to where i wanted it and later sold it.
I converted a 2000 stp by buying a adjustable hammer, a main spring, and a valve spring. I bought and installed a pickup assembly as well but the pickup assembly was not necessary but the stp pickup assembly is hollow and allows for external velocity adjustment.
I also snagged a rt feed spyder threaded sterling with current stp adjustable internals
Everything i have now runs the newer hammers and springs.
__________________
Proud Delta Ops member
playing for the betterment of the game.
My Feedback

Last edited by Tinman; 03-13-2013 at 09:35 PM.
Tinman is offline   Reply With Quote
Old 03-13-2013, 09:50 PM   #17 (permalink)
MCB Member
 
Join Date: May 2008

Quote:
Originally Posted by Tinman View Post
Ok, James I want to be sure we are talking about the same thing, there are 2 rods on the pump, one is the Pickup Rod the other is the Pump arm.

right pickup rod, I mentioned in an earlier post this thicker rod, but couldn't remember the proper term so the pickup rod is the one in question. Really though it should be called the pump rod as that is what it actually does. The socalled pump rod only moves the bolt back and forth, which isn't connected to anything else. oh well. pickup rod it is then since that is probably what the manual guys went with.

The pickup rod has two different thicknesses with a step in the middle of the shaft the thicker end being in the pump handle. because of the step in the middle of the shaft there is no benefit to changing the depth of this rod in the pump handle. The pickup rod will always enter the marker the same distance stopping at the step. This is where the stop nut (pickup collar)comes into play (large brass nut that the pickup arm slides through) by adjusting this nut you control the depth the pickup rod enters the marker.

true. I forgot about the step, though it seems I have adjusted pickup rod this way once or twice, not sure why it would have worked given your explanation. The brass nut sounds like a better plan. I didn't know it was adjustable. I'll check. Internally, the pickup itself can be adjusted and could be the cause of the op's trouble.
Note: the brass collar on my stp is round on the outside(is it adjustable inside or from the outside on yours?). I believe my old proline bronze was square or hex shaped on the outside.


When you change the pump arm position it only changes the position of the bolt.
unless you have it wound too far in and it impedes the pickup arm from being able to return all the way forwards. (causing trigger engagement issues)

true, my bad for using the wrong term.

In a pumping motion, The pickup on the bottom of the pickup rod compresses the spring and picks up the hammer and pulls it to the forwards position. ( If the pickup is too far forwards on the rod it may not grab the hammer, if it is wound too far out it will pickup the hammer but may not engage the sear properly )

I also wonder if the pickup is to far forward if it would put excessive pressure and open the valve a little?

I really don't want to argue the point that Springs have changed..But if i must, Hammers with the adjustable velocity nut are intended to have springs that are significantly lighter and shorter than proline springs Arrow has them listed as STP springs.
I ordered a handfull from Arrow for my Proline stp, it didn't work out. I cut spyder springs got it back to where i wanted it and later sold it.
I converted a 2000 stp by buying a adjustable hammer, a main spring, and a valve spring. I bought and installed a pickup assembly as well but the pickup assembly was not necessary but the stp pickup assembly is hollow and allows for external velocity adjustment.
I also snagged a rt feed spyder threaded sterling with current stp adjustable internals
Everything i have now runs the newer hammers and springs.
I think you misunderstood me. I totally agree that proline and Arrow sterlings use different springs. However, my stp (sterling threaded, vert feed, has adjustable hammer and super light springs) is by Arrow Precision and I believe was last sold around 2000ish shortly before the lull and the spyder threaded stockclass version came out. Maybe there were two different stps being released by AP during that time? I'm not sure why yours wouldn't have had the adjustable hammer or an adjustable bolt, unless it was actually an earlier stp or a bronze? I am under the impression that all stps had either an adjustable bolt or hammer as it was one of the main features that distinguished them from the bronze model.


replies in blue. Thanks for clarifying a few things, I've been educated and now must pay attention to my more important education that has a big quiz tomorrow. good night gentlemen and get the stp shooting sweetly
__________________
My MCB feedback: http://www.mcarterbrown.com/forums/f...ml#post2245661

For Sale: http://www.mcarterbrown.com/forums/m...ml#post3163559

wanted: cocker beaver tail, reg extender, black anno palmer reg in good shape, ANS 90 frame, mine rail that can be mounted backwards for more length (dovetail).
James_Blond is offline   Reply With Quote
Reply

  mcarterbrown.com » Paintball » The Armory » Sterling

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump


All times are GMT -4. The time now is 06:26 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO
© MCB Network LLC