Lowering fps help

[mirlock]

Hi Peeps

Tm Thompson slapped a kanzan strong motor and m110 and longer barrel mad bull python II tight bore 320mm (300m stock) and got 370 fps which was bang on what i needed.

Piston must have been crap as it ripped off the 1st tooth so i did an upgrade

200% Helical gears
Modify High Strength Piston
New Piston Head
Cylinder head and cylinder

Now the damn thing is 410 fps
how much do you think the spring will set to if i leave it compressed

failing that do you think m100 will bring it down to 370 or will it have to be a m90

Using branded Springs like Mad Bull

( i also could shorten barrel if it will help getting 370 )

Thanks in advance

[ChuckNorris56]

Re: Lowering fps help

An m100 MIGHT bring it to 370, or just slightly over. if your site limit is 370 fps, i would run the gun under that limit, because if one variable increases and your gun shoots over 370 you won't be allowed to use it, which would be a shame if you have just spend time upgrading it.

Before you spend money on a new spring, try compressing your current spring for a few days, and go from there. It it doesnt come down sufficiently, then change spring. Its important to remember that most springs require time to settle into a gun, so a brand new spring will gradually weaken with use, so dont be hasty to change spring if you dont get the results you want

[Genesius]

Re: Lowering fps help

I don't think compressing the spring will help. You've improved your arsenal and now the spring is putting out the power it should. Mif it were me I would buy a guarder sp90 spring and a spring spacer and chrono without the spacer and add it if it turns out a little low on fps. Pm me and I'll tell you where to get both items

[mirlock]

Re: Lowering fps help

Thanks for replies guys. Indeed i think 40 fps is alot for the spring to come down from it being compressed aand settling in.

But i looked at the spring chart that was tested with a upgraded p90 which is fairly simular to the thompson being both version6.
And it rated a systema m100 at 365 fps. so i went and got one of them and it chrono's at 379fps whih i think should come down to 365-370 fps after some settling in.

fingers crossed and thanks again for replies

[Crude Skinny B]

Re: Lowering fps help

You could always trim 1 coil of it if you have the means.

[mirlock]

Re: Lowering fps help

You could always trim 1 coil of it if you have the means.

I tried shoooting about 4k bb's and it didnt lose a single fps lol

Ive now trimmed a coil off and putting back to gether ill let you know how it goes

[mirlock]

Re: Lowering fps help

You could always trim 1 coil of it if you have the means.

Update .. Thanks Dude cut 1 coil off and its a solid 366 fps now