Advice on Downgradi...
 
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Advice on Downgrading 500fps to 350fps Please

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Barrie and Anne
(@barrie-and-anne)
Posts: 1124
Noble Member
Topic starter
 

Hello all.

After soldiering on with a DBoys K98 at a couple of rifle games, I have now decided enough is enough and I need to take the plunge and dial my ShootnScoot No.4 back to 350fps - from the 500fps I upgraded it to a while back in a fit of madness.

The problem is, the only springs that seem to be available are super ultra powered - like the one I foolishly bought last time.

The question is - can I just cut the spring I have right back? I'm thinking starting with 5 or 6 coils but might have to go much further than that and I just don't know if there's a minimum length for it to work correctly.

Our No.4s are APS2 L96 based.

Thanks.

 
Posted : 16/04/2014 7:35 pm
Sgt.Heide
(@sgt-heide)
Posts: 5882
Illustrious Member
 

Something like this http://www.fire-support.co.uk/product/p ... -thin-type should do it. You need to verify whether your rifle takes the thin or thick type of spring, which you can tell by the size of the spring guide.



When I want your opinion - I'll tell you what it is!

 
Posted : 16/04/2014 8:13 pm
dadio
(@dadio)
Posts: 3523
Famed Member
 

there is a limit to how much you can cut off a spring , the stopper (that is removed in order to remove the bolt) is held in by the spring pressure ,once you cut the spring so short that it has free play when not cocked then the stopper can drop out .my no4 home build has a spring that is loose when not cocked and to overcome the problem i had to pack under the stopper with foam rubber to stop it falling out , if you do the same then there is no real limit to how short you cut it .

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Posted : 16/04/2014 8:23 pm
Sgt.Heide
(@sgt-heide)
Posts: 5882
Illustrious Member
 

Additionally, the problem with cutting springs, is that they bounce around because they're not a tight fit and can damage the inside of your piston, as well as shake other stuff about. If you cut them too short and then have to pack them out to overcome the bouncing effect, you will also lose the fps loss that you had achieved. Cutting springs is always a false economy and, not an exact science in any gun.



When I want your opinion - I'll tell you what it is!

 
Posted : 16/04/2014 8:44 pm
Raffles
(@raffles)
Posts: 1402
Noble Member
 

Well given the amount of people who upgrade snipers someone may have a 350 spring from a project gun left over. Might be worth asking on some forums.

 
Posted : 16/04/2014 9:07 pm
Barrie and Anne
(@barrie-and-anne)
Posts: 1124
Noble Member
Topic starter
 

Thanks for the advice all.

I was thinking of maybe turning a wooden spacer to take up the slack of the shorter spring but it's just getting too complicated. I'll keep it simple and get a new spring. Unfortunately the Firesupport one is too thin for the spring guide but I've found this site which has just the thing - [link]http://www.x-fire.org/etop/bolt_sp_thicker.html[/link].

I'm now in limbo waiting for an email to confirm my order or something (not used to ordering from overseas).

 
Posted : 18/04/2014 4:19 pm
(@libris)
Posts: 35
Eminent Member
 

X-Fire are great to deal with although their order process seems archaic it is typical of a small number of Far East businesses dealing with us foreign johnnies. Actual delivery time is pretty good although it's a bit hit or miss whether it gets caught by customs.

- We don't stop playing because we grow old. We grow old because we stop playing -
- While growing old is mandatory, growing up is optional -

 
Posted : 24/04/2014 11:39 pm
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