Black Dog "skinny" mag modifications

[Richard in LA]

Ok, I have a bunch of skinny black dog machine ciener/atchisson mags that just will not work in my dedicated upper. just about every shot, the empty gets hung between the CH and bolt. I got frustrated and bought 2 full size mags, and they run great. I have searched the internet, and found out that I need to file the left side feed lip (one farthest from the ejection port) to allow the spent casing to hit the ejector. Has anyone else had this problem and had to modify their skinny mags? I am sacrificing one of my mags up to experimentation tommorow at precision to get this thing running, and would like to hear/see pictures of what works for you.

 

[Cajun_Chuck]

Ok, I have a bunch of skinny black dog machine ciener/atchisson mags that just will not work in my dedicated upper. just about every shot, the empty gets hung between the CH and bolt....I am sacrificing one of my mags up to experimentation tommorow at precision to get this thing running, and would like to hear/see pictures of what works for you.

Not really sacrificing it if it doesn't work with your upper. It might as well sit in a box at the house, so the experimentation is worth it. Go for it!!

Take some before and after pics, just in case someone has issues with this later on. They can always look it up in the photo (image upload) section and see how you resolved the issue.

 

[George]

havent used my black dogs yet, but i have the mock full size ar amgs

 

[Richard in LA]

Not really sacrificing it if it doesn't work with your upper.

Sure it is, I could sell all 20 of them, and buy the full size that work w/ my upper

havent used my black dogs yet, but i have the mock full size ar amgs

I have 2 of these, and they work well. The friggin skinnies that I got for brand new, $20 a piece, I want to work badly, because they hold 3-4 more rounds depending on if you have the LRBHO follower (which is **** btw). In fact I just ordered a couple more of them to have for the Sherburne shoot this weekend.
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Well, I went to Precision today, w/ 4 different types of ammo. 2 different types of Fed V.P., Federal bulk "auto match" ( or something like that), winchester 333 B.P. none of them would get off more than 5 w/o a jam in my modified BDM skinny mag. Constant jams between the CH and the bolt. It doesnt make sense to me, as the feed lips on the skinny and full size both appear to be the same distance from the ejector on the inboard rail??? I had to finally pack up and leave due to being frustrated Maybe I'll go back this evening and try again.

 

[wadepat2]

Maybe its the follower. I dont have any experience with the dedicated upper but you stated that was the only differince in the mags besides the appearence.

 

[Richard in LA]

This could be a possibility, and I hadnt thought of it. I will swap followers from one of the full sizes + skinnies to see if that works, since they come apart fairly easy.

Just an FYI, the feed lips on the skinnies, from the factory are different than the full size. I filed down the feed lips of one of the skinnies to match dimensionally (best I could), and still no luck

 

[Cajun_Chuck]

Sure it is, I could sell all 20 of them, and buy the full size that work w/ my upper...

Just an FYI, the feed lips on the skinnies, from the factory are different than the full size. I filed down the feed lips of one of the skinnies to match dimensionally (best I could), and still no luck

Well, I guess you can sell them then. I dunno...

 

[Richard in LA]

I'm gonna try one more time w/ swapping the followers around, but I'm 99.9% sure I got the "fix" to my problems coming in the mail, and should be here before the shoot on saturday