Increase Swept Volume & more in IHP

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tirths
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Increase Swept Volume & more in IHP

Post by tirths » Thu Apr 01, 2010 10:55 pm

NOTE: I am giving raw data, if someone interested to convert them in CC very much welcome to do so.

Lets see how your compression area looks like when nothing in:
Image

Now when the piston (with seal) inserted there look to be big difference. Yes, almost 24mm (wastage) in length.
Image

What I have done next. I made the piston small by made dovetail front part of it like this:
This thread has been edited to conform with Indian For Guns policy as stated in the Announcements forum

By which I gained fair amount of volume like this:
Image

Now this is how it looks the final product looks like:
This thread has been edited to conform with Indian For Guns policy as stated in the Announcements forum

Further more: Most of DYI guys know the fact that IHP having huge preload which doesn't enhance power. You can reduce preload by inserting this tube behind the spring guide:
Image

Any after that you need spring: Here is the specs:
Wire Dia: 3mm
ID: 12.7mm
Total coil: 39

Hope this help. Good luck!

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Basu
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Re: Increase Swept Volume & more in IHP

Post by Basu » Fri Apr 02, 2010 8:18 pm

dear Tirths,
refering to your image, there is a groove at the rear part of the piston, is that meant for any O ring or simply cosmetic ?

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Re: Increase Swept Volume & more in IHP

Post by Amaresh » Fri Apr 02, 2010 9:32 pm

Dear Tirths , nice one. The weight of the piston is reduced or it is maintained as the original weight.

Regards,
Amaresh.

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Re: Increase Swept Volume & more in IHP

Post by tirths » Sat Apr 03, 2010 10:54 am

@Basu: that is not cosmetics. It is a ring made with hard plastics to elemental metal to metal friction and most importantly wobbling.

@Amaresh: Yes, the idea also to reduce the weight. The ideal weight is 200g for the spring it can use (I may not give you the calculation).

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Re: Increase Swept Volume & more in IHP

Post by santhosh » Sat Apr 03, 2010 11:30 am

What is the cost of this

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Re: Increase Swept Volume & more in IHP

Post by t20 » Sat Apr 03, 2010 11:53 pm

Great Post tirths!

I used the seal in my IHP mod 25 what you are selling in This thread has been edited to conform with Indian For Guns policy as stated in the Announcements forum and I would say the gun performing very very well now. I must buy mod35 to try out this piston. Please let us know if it will be available for sale. Request you to think for mod25 also.

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Re: Increase Swept Volume & more in IHP

Post by tirths » Sun Apr 04, 2010 12:32 pm

@santhosh: This is not for sale. Just a prototype. I know only very few people will show interest for such product. I would be interested to see someone can do and enjoy the power and smoothness.

Jeetesh, missing your comments man!

@T20: Glad to hear you are happy with the seal and you are not the only one here. Well, may be I will do something for 25. I personally like 25. It is much rugged than 35 and moreover good for 10m.

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Re: Increase Swept Volume & more in IHP

Post by t20 » Mon Apr 05, 2010 12:24 am

Thanks!

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Re: Increase Swept Volume & more in IHP

Post by brihacharan » Mon Apr 05, 2010 6:09 pm

Hi Tirths,

> Simply awsome man! The height of basic physics & engineering.
> You must have this "PATENTED" - its your brainchild.
> The schematic diagrams & explanations are picture perfect.
> As I see it, it's not anyone's DIY thing - it's all about precision engineering.
> Hats off to you.
Cheers
Brihacharan

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Re: Increase Swept Volume & more in IHP

Post by vijaycool » Mon Apr 05, 2010 8:12 pm

Tirth,
Are you sure you can increase the S.V. as much as 16mm just by replacing piston. How does the cocking arm will have the reach of pushing down to the bottom. Or does the OAL(Over All Length) from crown to sear is identical to the stock piston?

cheers,
Vijay

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Re: Increase Swept Volume & more in IHP

Post by pkjeetesh » Wed Apr 07, 2010 12:44 am

tirths wrote:@santhosh: This is not for sale. Just a prototype. I know only very few people will show interest for such product. I would be interested to see someone can do and enjoy the power and smoothness.

Jeetesh, missing your comments man!

@T20: Glad to hear you are happy with the seal and you are not the only one here. Well, may be I will do something for 25. I personally like 25. It is much rugged than 35 and moreover good for 10m.
Thirths....that is a dream piston...make it happen...

reg

pkj

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Re: Increase Swept Volume & more in IHP

Post by tirths » Wed Apr 14, 2010 4:03 pm

Soon after the trigger unit pkj. Very occupied with some domestic responsibilities :(

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Re: Increase Swept Volume & more in IHP

Post by brihacharan » Wed Apr 14, 2010 4:12 pm

tirths wrote:Soon after the trigger unit pkj. Very occupied with some domestic responsibilities :(
> Hi Tirtha,
> The day you blow the whistle when 'The trigger & modified piston" developed by you are ready, I'll board the next train to Chennai with my IHP35 and get them installed by you.
> In the meantime I pray that your domestic responsibilities are fulfilled soon.
Cheers
Brihacharan

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