The JR Carbine Thread

I have a JR in 9mm that I have not fired since purchasing :( (approaching 8 mths now) ... Cant wait to get out with it. THey are nice little guns

you must have kids! Lol my rifles are my kids :). I can't go 2 days without taking a new rifle to the range.

Hope you enjoy it! Range report soon I hope!
 
I had huge feeding problems with the new KCI .40 magazine I bought... maybe I can file it down or do something that will make it feed properly. The top of the mag is getting chewed up... Korean garbage. Maybe these are just good in Glock pistols, not a JRC rifle. Anyone else have problems with these mags in your JRC?
 
I tried a KCI extended mag in a .45 ACP for my JRC. It would not feed at all, right out of the box. The follower wouldn't even go all the way to the top sometimes. They're junk...stick with factory Glock mags.
 
I had huge feeding problems with the new KCI .40 magazine I bought... maybe I can file it down or do something that will make it feed properly. The top of the mag is getting chewed up... Korean garbage. Maybe these are just good in Glock pistols, not a JRC rifle. Anyone else have problems with these mags in your JRC?

I tested three KCI 10/15's today in my JRC40 and found that every two or three shots it wouldnt feed correctly, getting jammed on the ramp. No issues with my glock mag at all either.

The first four are jams, the one on the right was never chambered. The first one in particular shows better detail than the rest of the groove cut into the copper, and all four have that similar mark. What the hell do I do to fix this?

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I saw these docs back when I purchased the JR, and I thought they were only for the 45ACP mags. I disassembled the KCI's and adjusted the end of the spring by bending it up as one of these docs suggest. I noticed that it slides off the floor plate so I adjusted them again to bend the tip of the spring in so it is "under" the plate instead of at the edge. That seems to have increased the pressure of the spring a little bit. I loaded it up with my uplula and then manually emptied it with my thumb, and immediately noticed that the bullets don't "drop in" during loading, and catches on something when I unload with my thumb. I shaved some of the plastic off the inside of the feed lips so it would be flush and smooth, and bullets drop in now and unload much more smoothly. I'll try to get to the range tomorrow and try it out.

I'm considering replacing these springs altogether as recommended by other sites, and hopefully find followers to replace too. The inside of these KCI mags are smooth, so would a #5 glock mag follower be what I'm looking for? The follower still jams slightly when there is only 2 or 3 rounds left in it, changing the angle of the feed and not seating the round against the lips fully -- but the feed jams I described in my other post would happen on a full mag on the 2nd shot. Apparently these KCI mags are "only good for the range" and people tend to use them for feed jam practice. LOL. Also I noticed that the angle/slope of the round on the lips is slightly steeper (2 or 3 degrees) than the glock mags, which I think should help but could be the problem.
 
get rid of the junk KCI mags and just buuy good ones. the amount of time and money you spend on the KCI you could buy OEM mags for less

That's good advice. Why can't we get any pinned Glock 15-round G22 mags? I haven't seen them for sale in Canada anywhere. I went ahead and ordered Wolff +10% springs, a 10-pack. I'll try them out and post results. I'll have a few extra to get rid of, if anyone is interested.

The follower seems to stick slightly at the 3rd round after my mods. When I push down the 2nd with the uplula (to insert the 3rd) I noticed the stick, seems like a stronger spring might overcome that. I wonder if there is anything I can coat the inside with to find exactly where it is rubbing? Or where on the follower it is rubbing?
 
I have 1 KCI mag. My JR doesn't like it. So it stays in my Glock.

You think someone on the EE would buy my KCI mag 'as is' for $10-15 (paid $30+tax) for their Glock pistol? I'm assuming these work better in their Glock pistols...

I've yet to test it in my TDC, will do that before I consider getting rid of it.
 
Hey Pete, I just bought some from Reliable Gun. Also Wolverine also has had some in the past. That is where i have bought mine in the past.

I got my mags from wolverine too. Waiting to hear back from them about one KCI mag that somehow shattered in storage. Weird spiral shattering of the plastic. And I kept them in a padded case inside mag paddles.

The KCI mags never had an issue when I first got them. They were fine for a couple of months and then I just let them sit loaded for a couple more months, and when I got to the range I found these problems. I'll post pictures of the shattered mag after I hear back from wolverine. Hoping there is warranty or something to replace it. In the US these mags are like $10 so I wouldn't care, but cross the border and they're 400% that price..? Yeah I want a warranty replacement. $10 I'd just post a pic and toss it.
 
I got my mags from wolverine too. Waiting to hear back from them about one KCI mag that somehow shattered in storage. Weird spiral shattering of the plastic. And I kept them in a padded case inside mag paddles.

The KCI mags never had an issue when I first got them. They were fine for a couple of months and then I just let them sit loaded for a couple more months, and when I got to the range I found these problems. I'll post pictures of the shattered mag after I hear back from wolverine. Hoping there is warranty or something to replace it. In the US these mags are like $10 so I wouldn't care, but cross the border and they're 400% that price..? Yeah I want a warranty replacement. $10 I'd just post a pic and toss it.

Bought my KCI mag at Wolverine. Even if there is warranty work, it would probably cost me about $12 to ship this $30 mag back to them... no guarantee the next KCI mag they exchange will work in my JRC.

If you read their thread on KCI mags, I don't think they'll exchange or refund unless they're in 'new, unused condition'. Guess we both are out of luck.
 
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I've been thinking I might need to pick up one if these in 9mm.

The question I have is, do you have to use glock mags or can they be converted to take, say CZ 75 mags?

I have a CZ 75b so this would be pretty handy.
 
I am not sure if they can be converted. But I can tell you that the JR is a great rifle. I haven't had any issues outside of KCI mags. And with even fewer non-res choices these days now might be the time to grab one.
 
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