I was told that SP necks were bad for ICD markers. They said the thread pitch is the same but the diameter is different and it will strip if hit or dropped. So I decided to do some checking of diameters with a caliper.
Feednecks that Pass
Note ICD spec is .812
ICD B2k4 Stock feedneck =.818 another B2k4 neck = .818 This neck is shouldered doesnt fit on 05 FS
ICD 04 Stock Freestyle Feedneck = .809
- Yes measured it three times
AKA BM2K Feedneck = .811 This neck is shouldered doesnt fit on 04/05 FS but does fit an Fs7 very well http://www.akalmp.com/feedtubes.html
ICD 203006C Clamping Feedneck, = .807 http://www.icdpaintball.com/accessories.htm
FeedNecks that Fail
CCM Bushmaster Medium Rise Feedneck =.801
(thought this was supposed to be "the" feedneck?? It looks like we are getting SP threads sold as bushy?)
Macdev Sonic Lowrise Bm2k -.801
Shouldered Neck so it may be more secure in markers like a b2k over non shouldered This neck is shouldered doesnt fit on 05 FS
NW Paintball Products Bushmaster+ =.803
(I have a few)
NW Paintball Products Impulse/Ion
(just got it off ebay different label than the bushy one )
Generic Clamping feedneck =.801
Repeatablity was good, so I trust the numbers
And yes I tried to fit the B2k4 feedneck in to the 04 FS, it has a shoulder and hits about 1/4 thread before stopping
Edit 2-20-10 there really isnt a pass or fail
Im thinking, like I said before its all a tolerance stack - that leads to problems. Some people have no problem with the smaller SP threads, others have reported striping.
If you happen to have a slighly oversized body and a slightly small feedneck you could pull threads. ICD has never been known for spot on tollerances. I have bodies that the smaller necks fit very well in and others that sort of rattle around very loose before they are tightened down.
The Import B2k4 body I have is the worst - its feed neck was 818 and fit the body very well. You put one of the .801 necks in there and its very wobbly.