SP-01 shadow (what are the lightest springs and still get positive ignition?)

[scottinohio]

What springs and where to buy??  THX  Scotty   PS have extended firing pin

[OpenshooterMclass4lyfe]

An 11.5 hammer spring will still ignite majority of primers.  8.5 will only work reliably for federal primers.       I had an 8.5 in one of my original shadows and it would ignite cci (for the most part) and federal but was hit or miss with just about anything else.     Cajun gun works for all your CZ shadow parts btw. 

Edited April 25, 2022 by OpenshooterAclass4lyfe

[Foxj66]

I use Cajun 11.5 hammer springs and Rami firing pin springs. All 4 of my shadows will reliably light off SRP. You will need to ensure you have your primers seated deep enough as well.

[SouperMan]

Extended Firing Pin with 8.5# Hammer Spring with Federal Primers is probably the lightest you can go. I’m sure you can get it to work going lighter, but you’ll be chasing reliability. 

[MNshooter]

I’ll pile on. 8.5# Federals. 11.5# CCI WIN and FED all day. I did add the extended CGW firing pin. 
 

I would offer that you try a few. I prefer the 11.5# over the 8.5#. Not as mushy. 

[GeneBray]

My SP01 with a 8.5 MS had issues with all Russian primers.  CCI, Winchester, and Federal work significantly better than Russian.  That said those primers were not 100%.  Actually I have had 100% primers with any MS weight upto and including stock.  Eventually a bad primer will slip through quality control.  11.5 lb is better tha 8 for reliablility IMO.  The penalty is heavier trigger pull.

 

 

[Lightj75]

This is all assuming you have the extended firing pin and reduced power firing pin spring as I did with these results.

 

8.5# federal only

9# federal only 

10# fed,win,tula,cci, rem 

11.5# all of the above and cci #550 SPMP 

 

I never tried cci SRP with the 11.5# but I know they will not work with the 10# atleast not in my SP-01.

Also I think the 10# will set off the cci #550 but I can't remember for sure so I left them out. 

[WYgunner]

Running an 11.5# CGW mainspring and a rami FP spring.  I don’t have an extended firing pin and my setup will ignite Winchester spp and fiocchi reliably.