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All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: kevinbrian on September 08, 2012, 02:41:09 PM

Title: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: kevinbrian on September 08, 2012, 02:41:09 PM
Good afternoon friends. My new spring came in the mail today. He actually sent two!!! I'll email him when I am through making this post and let him know that he sent me two instead of one.
 First, after removing scope (I used masking tape to mark where the mounts where) and removing the stock, I removed the bolt, and the endcap.  I them slowly and carefully backed out the 1/4 inch Allen screw counting the turns precisely. The factory had mine set 3 and 3/4 turns in. I adjusted NOTHING else. I kept the hammer preload Allen screw (1/4 in) backed back until it was stopped. I slipped out the old spring, put in the new. Put gun back together, filled two clips with Exacts, and went to the basement where my chrony was waiting. First shot on a 3000 fill was 809 fps.  My factory setting with factory spring would have been in the 840's. SO......still using the new spring, I started making quarter turns of the 1/4 inch hammer preload screw until my peak velocity was 873. It took all of 15 minutes to find the rainbow, since I was determined NOT to adjust the other two adjustments. What have I gained? Well, I don't know. I could have screwed my hammer preload in a half turn and gained the velocity that I did (in full factory config). But this spring seems more robust and less likely to take a set.  I can easliy have my gun shooting identical to what it was by backing the 1/4 in screw out a quarter turn. But I decided that I wanted a bit higher peak velocity (873 fps). Here is the present shot string using a 210 BAR fill: 855, 860, 861, 866, 868, 870, 871, 871, 868, 873, 868, 867, 864, 861, 861, 856,  Ending pressure was 160 BAR.   That is 16 shots with an extreme spread of 18 fps. Not too bad eh? I have not shot for accuracy, but since I didn't remove barrel, or change anything else, i am satisfied that accuracy should be the same. If it's not, I will back the hammer preload out one quarter turn bringing peak velocity into the early 860's (like it was), and THAT should do it. I SURE wish that one of you engineers would create a drop in "slingshot" valve like my Daystate Huntsman has in it!!! I'd like to see if air usage could be cut down while velocity stays the same, if that's possible.
 QUESTION!!! Can I take a q tip with some blue locktite on it and wipe around the threads that I see through the back cap? The thread that the 1/4 inch Allen are riding on??? Wouldn't that lock my adjustments in place?? By the way, the factory had put NOTHING on those threads as the allen screw turned very easily and didn't need extra force to start it (when I started counting turns when I first started).  Thanks y'all. I will now perform a field test and see if accuracy is same.
Title: Re: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: Motorhead on September 08, 2012, 03:08:35 PM
While End Cap is off, drill & tap it for an 8-32 set screw. ( Use Plastic tip set screw of place a piece of weed eater line in front of set screw )

http://i7.photobucket.com/albums/y297/pad617/boltclosed_small.jpg (http://i7.photobucket.com/albums/y297/pad617/boltclosed_small.jpg)

Picture NOT mine and with the factory bolt handle passing by on right side, placed my lock screw mod on LEFT side  ;)
Title: Re: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: kevinbrian on September 08, 2012, 03:42:48 PM
Man that's a great idea!!!!!!!! I even have an 8x32  drill and tap. Does it REALLY matter about the weedeater line and plastic set screw though??? I didn't quite get that part.  How about i drill a hole and tap it 8x32 like you said, and use a short set screw of brass since I don't plan on changing it alot. I will go back and read your post and try to picture the weed eater line and stuff. I am just a little slow today. lol
Title: Re: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: Motorhead on September 08, 2012, 03:59:42 PM
Man that's a great idea!!!!!!!! I even have an 8x32  drill and tap. Does it REALLY matter about the weedeater line and plastic set screw though??? I didn't quite get that part.  How about i drill a hole and tap it 8x32 like you said, and use a short set screw of brass since I don't plan on changing it alot. I will go back and read your post and try to picture the weed eater line and stuff. I am just a little slow today. lol

Because the threads are so coarse  on the preload adjuster, just running a metal tipped set screw down onto them will SCREW UP THE THREADS !!
The nylon tipped set screw or *weed eater line allows preload adjuster position to be retained while still allowing forced rotation so adjustment position can still be changed easily WITHOUT thread damage.
Title: Re: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: kevinbrian on September 08, 2012, 05:39:06 PM

Because the threads are so coarse  on the preload adjuster, just running a metal tipped set screw down onto them will SCREW UP THE THREADS !!


  Okay, got it. Loud and clear.  THANKS FOR CLEARING IT UP FOR ME!!!!  ....lol   Sure enough, I appreciate it.  I'm just not the sharpest knife in the drawer and sometimes need stuff explained to me. I'm obliged.
Title: Re: Marauder w/ #10 Spring (shot string) (I have a question, too)
Post by: Talon22 on September 10, 2012, 05:36:51 PM
Kevin,
A friend of mine on another forum makes hop up valves and gauge blocks. I haven't tried them out but, I plan on it when I get back to work. Very good prices and nice looking work.
http://www.addicted2airguns.com/ (http://www.addicted2airguns.com/)
dave@addicted2airguns.com