Gunsmithing HELP Standard practice on cutting springs?

[RJN]

Need a little help here on the standard practice concerning cutting or not cutting springs.
I just received a new firing pin and firing pin stop from CZ-USA for a CZ Kadet .22 conversion kit for a 9mm Shadow. The old firing pin spring is 2" long. It is to long to work with the redesigned firing pin. When I notified CZ-USA of the problem this was their reply instead of sending me the proper $2.00 spring: "The current spring measures in at 1.315” long, so you’d need to trim your old-style spring down until it functions properly".
So, is it bad practice, like the first thing you learn in gunsmithing school to not cut springs or am I off base and should I just cut the spring?
Thanks for the help Rick

 

[NXS338]

A spring is a spring so weather you cut it or the spring manufacturer cuts it there is no difference. The only problem I see with your situation is the diameter of the spring wire of these two different springs. You can have the same spring pressure with two springs of different lengths but the wire diameter has to change, provided the coil sizes and spacing is the same. Its a two dollar spring, cut a few coils at a time till it works. I have heard the same thing about never cut springs, I have also seen alot of them get cut by some of the best in the business.

 

[RJN]

NXZ338,
Thanks for the info. I've always thought exactly what you said. The diameter of the wire and number of coils determine the 'strength' of the spring, not just the length of the spring. That's why I'm a little pissed CZ-USA would suggest cutting the spring not knowing if the wire diameter and number of coils per inch were equivalent.

 

[Turd in the Pool]

Any decent shop will have a spring assortment. A few minutes digging should turn up just what you need ;-)

 

[cal50]

Use sharp nippers or a cut off wheel on a Dremel tool to cut coils.
If you make a "cut" with nippers and do not go all the way thru the indent will leave a stress riser and the spring could possible crack / fail in that area.

Its easier to cut an extra coil off if needed rather than go too far and put it back on or leave an indent.

 

[NXS338]

You may get one of these, I made my own version but this can tell you exactly what a spring is loaded at. Believe me when I tell you, when you actually have a way to test weight springs you will be surprised at the variation in springs even when they tell you they are same weight.

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[NXS338]

Recoil Spring Tester Digital

 

[Hill Country Gunsmith]

I've cut thousands of coil springs with no problems. The only time I've ever gotten myself into trouble is cutting them too short to allow them to work. I keep spring stock in the shop so it's pretty easy for me to make a replacement, though. Springs are cheap so go ahead and experiment.

 

[RJN]

Thanks for the advise. The spring tester looks like a good tool. Where's the best place to buy a spring assortment for gunsmithing to keep in my shop?

 

[cal50]

NO. 71 COMPRESSION GUN SPRINGS | Brownells

 

[Turd in the Pool]

Thanks for the advise. The spring tester looks like a good tool. Where's the best place to buy a spring assortment for gunsmithing to keep in my shop?

I got lucky and nabbed a few boxes from a shop liquidation off ebay. Wolff is the best game around these days. They make a small spring assortment that is great for firing pins and extractors etc. Last stuff I got from brownells was disappointing.