Anyone got a CZ858 with the 10 round mag adapter?

The gunsmith at my local gun store machined mine. Apparently he had to machine slightly deeper(shave off a little more metal) than the instructions said in order to get the xcr mags to "click" in securely. Every mag needs to be pressed up very firmly to get it inserted and "clicked in". It not so bad once you get used to it. One thing too, which I think has been mentioned by others, is that the bolt carrier has to have full force and slam hard to chamber the next round. Letting it slowly go forward wont load the round from the mag into the chamber. This said it is not a huge issue if you can just adjust accordingly and rack the charging handle back and let it fly each time. My reverse charged bolt carrier(handle on the left side for faster/easier reloads) is on its way :D

Seems that perhaps not all the cz 858 rifles have the same receiver dimensions after all. I had been suspecting this before after my experience fitting various other accessory hardware.

Bottom line....the adapter works, 300rds no issues, shooters are required to slightly alter their operation of the rifle, but its worth it for the awesomeness of 10rd mags.
 
StonedAssassin said:
Apparently he had to machine slightly deeper(shave off a little more metal) than the instructions said in order to get the xcr mags to "click" in securely.
Click to expand...

I just received my adapter and mag in the mail last week, and did the machining myself yesterday. That made me a bit nervous, especially since the warranty I gave myself really sucked. I noticed the amount they called for to be taken off digs into the feed ramp by about .030-.040" or so. I tried the adapter when I just skimmed the bottom or the ramp, but it wouldn't click in, so I had to go deeper, although it worked for me at about .005" less than the official number. Not a whole lot.

In hindsight, I wouldn't take as much off under feed ramp, since it doesn't actually interfere with the magazine, and since there's a cutout about large enough to fit it. It's only the front corners or the mag that stop it from fully clicking in. Only thing I could think of as a possible problem with leaving a bit more under the feed ramp is that it would hang over into the mag a bit more, and possibly catch the tips of the rounds. Not sure if that's likely to cause a FTFeed or not..


StonedAssassin said:
One thing too, which I think has been mentioned by others, is that the bolt carrier has to have full force and slam hard to chamber the next round. Letting it slowly go forward wont load the round from the mag into the chamber...
Bottom line....the adapter works, 300rds no issues, shooters are required to slightly alter their operation of the rifle, but its worth it for the awesomeness of 10rd mags.
Click to expand...

Mine also required a bit of force to close. If I ease it forward, it hangs about 3/4" or so out. Kinda hard to see what's causing it. Otherwise, it feeds and cycles snap caps fine (haven't been to the range yet).

Oh yeah, and if you have a POSP scope mounted on that old side rail from Interammo, it interferes a bit. I had to take about .040", 1 1/4 long off the top of the adapter to get the scope to slide on. Won't be an issue for most.
 
2CentTactical said:
Will the extended bolt catch still work with these?
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Yes it will work. Like some other people I unfortunately bought the extended mag release and bolt catch combo before I found out about this adapter. The mag release gets replaced by the adapter but the extended bolt catch/release remains for easy locking back of the slide to show an empty chamber. Hope that helps.
 
StonedAssassin said:
That is exactly what was happening. So instead of taking more off of the feed ramp lip, the gunsmith just took a little more off in each corner to fit the mags. Seems to have done the job.
Click to expand...

I think they may want to revise the instructions they send out with the adapter so the feed ramp can remain untouched. They DO say (something along the lines of) "Don't alter the depth of the remaining feed ramp", so I can see they were worried that it could be an issue. But really, once you're set up to take the cuts, avoiding the last, say, .050" of the feed ramp, but getting in deep enough to get the corners in would be easy enough. 10 extra minutes?

Sorry if Wolverine raises the price of machining. I owe you all a beer or two (** void in certain locations, like North America)

When I get a chance, I'll try with the old magazines as well, and keep a close eye on it to see if that shorter feed ramp is a prob.
 
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Brugger & Thomett CZ 858 Magwell fitting 9th March 2012
Based on the results of the machining that we have had carried out on the first CZ 858 rifles we are refining our machining instructions. This is due to different tolerances from rifle to rifle. Measuring front to back machine out 63.6 mm not 64.6 mm, some final fitting by hand may be required so the magazines drop free. We have just test fired 15 rifles and all worked good with FMJ ammo. This adapter was designed to use the XCR 10 rd pistol magazine.

The Magwell adapter is $185 and we will be charging $75 to machine, fit and test fire a rifle.
 
I was going to post a question, but I got all the answers that I need, thanks John (Wolverine supplies), I think I will send my CZ-858 (7.62x39) in the near future!!
And I need some .223 10-round mags too..... do you also sell the couplers?
 
Just checked. They have the couplers. :)

Want to get a cz 858 for myself someday too as a fun gun. Reliable, and would be cheaper to plink and rapid fire at the range. (when it's nazi-less)
 
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