My ISSC MK22

Rootzee said:
I removed the firing pin stop, and 2 coils from the FP spring. 200 round today, and only 2 light primer strikes. Sweet. I may take another coil off, and other things. I was shooting Winchester Super X high Velocity ball ammo. This is good as its easier for me to get that over CCI mini mags. I also have to get a new optic as my red dot sight was very hard to get on target at 25 yards. I'm thinking of some magnification. All in all, this is a fun azz gun. Next weekend it's going to be a gophers worst nightmare!
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While your firing pin is out, stone it to get rid of the sharp edges left from the stamping process. I did that, and removed four coils from the return spring, and haven't seen a light primer strike since.
 
Rootzee said:
Stoning and coil removal will commence when I clean it tonight!
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Just to be clear, when you stone the pin, do both sides. You should end up with one side with a nice outline of bare metal, and the other side will have the same look, but be bare metal with a black finish outline. This side is referred to as the belly. Light lube when you reassemble the BCG. The FN forums all state 4 coils as a start with the return spring, so I'm not sure how 2 coils seems to be the norm on this site.
 
I just did 2 coils. I was following my own gut. I didn't want to risk any slam fires, which is always a risk from what I've read about firing pin springs. I've only read the FN forums with regards to the MK22, and figured I'd do 2 and go from there!

Thanks for the tips on the firing pin!
 
When I did my coil trim I started with 2 to see how it would go. From my experience on my rifle that's all I needed. Every rifle is different and most seem to go with 4 coils cut on the fn forum. I get the feeling since I had posted my feedback on the 2 coils cut that its what most are starting with now. No harm in starting small regardless. If you're still getting some light strikes but maybe less frequent, the logical step would be to trim another coil or 2.
 
I see no problem starting off on the safe side, I did not mean to imply that. I did the same myself, except, that the safe number at the time was 4. People on the other site have cut off what I would think is a very unsafe amount. I guess all I ment to say was that 4 coils was my magic number. fchan, keep up the good work, your posts have been very help full in regards to this rifle.
 
Bowzy,

have you used the Nc Star scope yet? If so what did you think?

I'm using a Aimpoint style red dot, and although it works good and holds zero, I need the magnification (must be I'm getting older I suppose). The Sightmark Combos both you and Fchan have are right up my alley, but I can't seem to find them anywhere (without spending close to $400). I have actually considered an Eotech that I can purchase through my cousin, but it may be too much for this rifle. I would prefer a HWS over a scope, as I can't seem to get used to the eye relief on the scopes. It just bugs my eyes out for some reason. What's the eye relief like on the sightmark magnifyer?
 
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willisworms said:
I see no problem starting off on the safe side, I did not mean to imply that. I did the same myself, except, that the safe number at the time was 4. People on the other site have cut off what I would think is a very unsafe amount. I guess all I ment to say was that 4 coils was my magic number. fchan, keep up the good work, your posts have been very help full in regards to this rifle.
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Thanks man. I didn't mean to come across standoff-ish if I did. I was moreso trying to outline my experiences and why I went with 2. As you mentioned there were some guys out there happily trimming coils every time they had a light strike which I don't think is a smart/safe way to go about it. And you are right. It seems that 4 is the magic number for both but I think with a good stoning of the fp and using good ammo, 2 is a great place to start.

Al that being said, I only have about 400 through since I chopped my coil. We'll see if I need to go deeper over the longer run. Also, if you guys get the chance to do the trigger mid, I highly recommend it. It's reversible, quick, and takes out that quarter-mile take up
 
Rootzee said:
Bowzy,

have you used the Nc Star scope yet? If so what did you think?

I'm using a Aimpoint style red dot, and although it works good and holds zero, I need the magnification (must be I'm getting older I suppose). The Sightmark Combos both you and Fchan have are right up my alley, but I can't seem to find them anywhere (without spending close to $400). I have actually considered an Eotech that I can purchase through my cousin, but it may be too much for this rifle. I would prefer a HWS over a scope, as I can't seem to get used to the eye relief on the scopes. It just bugs my eyes out for some reason. What's the eye relief like on the sightmark magnifyer?
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Eye relief on the sightmark 7x is only like 1.5". Closer than you'd think you have to be, pretty sure the 3 and 5x you have more breathing room. One thing I noticed is comparing it to a traditonal scope, it seems more like a 5x. It's good for the money though.

The NC Star 3-9x42 mildot scope isnt the best quality glass. Keeping the gun still and looking through the scope, if I wobble my head around in a circular motion I can see a fish eye effect. If I was able to try it in person first, I probably wouldn't of bought it. Reticle is also a little thick for my liking.
 
Oh as a side note, the supply sergeant at the west Ed mall carries the sightmark 7x. It was $155+tax. Same as most retailers but if you're local you save on the shipping. I picked one up a few weeks back. I prefer the higher magnification to the 3x
 
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I noticed that the sightmark magnifier does not work very well with a sightmark optic. Something to keep in mind, they recommend it for use with aimpoint or eotech. Sightmark with sightmark combo can create ghosting. I thought it was just my eyes but after mounting my eotech xps2 it's a world of difference.

They've even state it on their website:
http://www.sightmarkonline.com/product/sm19024
"Not suggested for use with SM13005, SM13006, SM13041, or SM14000 due to minor ghosting."
 
Well I stoned the firing pin, and took another 2 coils of the spring. I went to the range today, and I'm sad to report that every 3 or 4 shots was a light primer strike. It was frusterating beyond belief. I have yet to tear it down as I had to go to work, but I'm really hoping that I can figure this out. At one point I went through 6 rounds before I was able to fire one off. I'm hoping I didn't over do it on the firing pin, but I followed Willisworms previous post on stoning both sides (I'm not blaming anyone but myself, I risked it out)

Anyway just thought I would fill you all in.
 
I'm sorry to hear that. Have you checked the bolts holding in the bcg? The other thing is to make sure your chamber is clean. Residue buildup on the chamber face can create a cushion that softens the impact resulting in a light strike.
 
Rootzee said:
Well I stoned the firing pin, and took another 2 coils of the spring. I went to the range today, and I'm sad to report that every 3 or 4 shots was a light primer strike. It was frusterating beyond belief. I have yet to tear it down as I had to go to work, but I'm really hoping that I can figure this out. At one point I went through 6 rounds before I was able to fire one off. I'm hoping I didn't over do it on the firing pin, but I followed Willisworms previous post on stoning both sides (I'm not blaming anyone but myself, I risked it out)

Anyway just thought I would fill you all in.
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Something else has happened here, There is no way that stoning the pin and removing two more coils can make your rifle worse. Have you moved the washer behind the BCG? can something have gotten caught up on re-assembly? What ammo are you using? Most ammo works in mine, but I prefer blazer. I have a brick of some super X that will not fire at all! about 98% failure to fire, not sure whats with that stuff. Any way, I would make sure you assembled everything correctly, very light lube, washer placement as stated here

http://www.canadiangunnutz.com/foru...IGHT-STRIKE-PROBLEM-OR-MISFIRE&highlight=issc

If this does not help, post up a reply listing all your mods, and we will try and troubleshoot this with you.
 
I'm gonna strip it right down tomorrow on my day off. As far as reassembly I'm confident it went together properly. I detail strip and clean this rifle everytime. The only mods I've done are..trimmed FP spring, stoned firing pin, new bcg hold down bolts, with threadlocker, and removed the firing pin stop. That's it. I have not placed the washer as the above link suggests, but I've read (fn forum) that is not a desirable thing to do. Have you done it?
 
Rootzee said:
I'm gonna strip it right down tomorrow on my day off. As far as reassembly I'm confident it went together properly. I detail strip and clean this rifle everytime. The only mods I've done are..trimmed FP spring, stoned firing pin, new bcg hold down bolts, with threadlocker, and removed the firing pin stop. That's it. I have not placed the washer as the above link suggests, but I've read (fn forum) that is not a desirable thing to do. Have you done it?
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I did move the washer, the early posts on FN were that this was not a wise move. However in the end, it was agreed that this was a viable option. The problem with such a monumental
Thread like the FN one, is that early on there was a lot of conflicting information. Most people run out of steam reading it before the solid work was figured out. If none of this works for you, I would start to look at the washer/spacer on the hammer spring mod. This will give the casing a solid wack!
 
At this point I'm gonna try everything. I spent too much money on this thing for it not to work properly. I read the entire thread in fnforum, even before I bought the mk22. I knew what I was getting into. So the washer on the hammer spring, does that go between the brass retainer and the trigger group housing( if that makes sense?)?
 
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