Does anybody know if this --> http://www.airguns.citymax.com/catalog/item/251488/5614578.htm
is a direct replacement for a 350? The number of coils stock is 39 I think but the other
measurements I'm not sure of. It seems pointless to try and get in touch with them directly
as they seem too busy for that.

That spring is probably aimed at the Patriot/Kodiak. The wire diameter and inside coil diameter are both larger than the spring JM occasionally makes for the 350. I doubt it would fit into the 350's piston, and if it did, the wire diameter would likely result in an oversprung gun.

Jay, you should contact Warren, He knows more about springs than I could ever hope to know. If he see,s this post, Im shure he can be of assistanse. Good Shooting Bud, Tim.

took me a while, there is church on Sunday for some of us and isn't it sunday today??

universal ultra mag .615 ID, 39 coils and .148 wire you said

the 350 is .560 ID, 33 coils and .128 wire

SOOO, NO it will not fit

warren

PS: the key is the OD not much the ID (.560 for the 350, 48, 460 ei. MAGNUMS)

and remember "it's 30% the gun and 70% the shooter"

Thanks, I'll guess I'll just sit unpatiently for another
spring to pop up on there that will fit.

This spring can certainly fit in a 350 with some modifications to the compression tube but if you really look at the OD it's not that much wider at all, just longer. We are talking 1/2 of a tenth of an inch OD which is 5/100's of an inch or 0.05". A Kodiak/Patriot spring was almost in my gun(!) so don't say "it won't fit" Warren You forgot what Curtis can do. I had to come off my power high for a minute and say "no".. I know it doesn't sound like me does it? Then after I hung up the phone with Curtis, I was like "hmm.. Kodiak/Patriot power in my 350 and I said no?" Could hardly sleep that night

Maybe my next .25cal 350 will have this fine spring in it.
Never say never, I mean.. "no it won't fit"
I actually think the 350 will be a great platform for this spring. Just make sure you put weigh down the piston enough with some good brass or SS top hat, button the piston and compression tube well with strong buttoning material, etc. and walla, you have a high 20's FPE 350. The only other thing is that you may need a more powerful (custom) piston to get the most out of this spring but I believe it's doable.

I should have said "will not fit as a OEM spring"

sure you can put a Frd 302 engine in a Bitish MG car, I saw one but at what expense?

bbgunbob put a 350 JM spring in his Crosman Quest in .177 and then changed the barrel tyo a Lothar/Walter .20 cal

you need to modify a whole lot of things to take advantage on a change from OEM to another brand and the know how to do it

warren

PS: You are right Harry, never say NO but I still have the e-mail from JM about this issue in which HE said it will not fit