[pump]

oh comparison pics please

[DonF]

Nw Bushmaster plus - MacDev Lowrise - B2k4 Stock Neck - AKA

NW isnt a bad neck strong threads, slightly bigger than CCM Threads (much smaller than aka) and the metal doesn't round like the CCM threads after a few removals. No shoulder = good or bad depending on what marker you have. It fits all ICD fairly well.

Macdev - Not what I expected. smaller threads, not many threads compared to stock - Has a shoulder - this is the low rise, I would hate to see the high rise!
Put it on my blind loaner B2k so the added height might help ball chops.

I dont mind the o-ring feednecks they hold Vlocity / Egg tight!

AKA - Short height, big diameter threads, plenty of thread, shoulder but more $$$ I can buy three NW necks for one AKA Have to really crank the screw down to get it to hold the Vlocity, but it gets there.

Some markers like FS4/5 cant use shouldered feednecks.

I have come to the opinion that no SP thread necks with ICD is not totally true. Its just that ICD or other feedneck manufactures didn't give much thought to tolerance stacks. So if you get a loose ICD body and a small (even for SmartFarts) threaded neck or one with just a few threads I can see how you could pull threads. All of the necks fit ok, there is noticeable rock in the smaller ones before they are tightened. The AKA fits all of my ICD bodies that are made for a shouldered feed neck the best by a noticeable amount. I think it was designed that way and the specs are held during manufacture.

[pump]

seems that the Mac Dev is just SP threaded with a shoulder

[DonF]

Yes that is what the Macdev measured out as, its my least sturdy and least thread length. The shoulder sits down into the B2k4 good though. I wouldn't use it on rare body that I cared about.

Goldie said he used to sell the NW necks with no problems, really they are pretty good for the money when you find them - unless you have a halo with the big honking stem.

[pump]

yeah i dont even consider SP threads as ICD, never go on my guns hell no

ICD shouldered or NOTHING

[DonF]

Updated some info on the 1st post - I was suprised to find the ICD clamping feed neck at 807! 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.

[Monke]

i'm not sure if this was said in all of your discussion, but what if the bodies themselves weren't set to a certain tolerance, hence why some people are happy with the SP threaded feednecks. could anno cause a variance in the tolerance too? then in that line of thought, could anno rub be affecting how well a feedneck fits?

[DonF]

Ano is .001 - .0015 or so.The problems start at .01 and get worse
My b2k4 neck is .818 and CCM is .801 thats a .017 or seventeen times the thickness of ano = very sloppy fit in that body.

[pump]

i think the useage of SP necks in ICD guns is just due to ignorance more than anno and machining variances

i think the non shoulder ICD necks are just as bad as SP necks, since all the force is put on the threads