tdbru Wrote:i just tweaked one of the mags i have for the mini howa in 6.5 Grendel. it does indeed now hold 7. and feeds fine. but in my mini howa 7.62x39 it won't feed anymore, the 7.72x39 rounds nose dive. so..... if you make the magazine mod, it's changes the mag so it feeds for Grendel only, which if that's all you have, no issues. at least that's what i'm seeing with my mag mod. ymmv.
-tdbru

tommyguns Wrote:How did you do it?

1075 tech Wrote:Essentially, it sounds like you're following the same steps used to make the 4 round "flush" fit mag. Just not cutting the body down.

I used a thin bladed coping saw for the major work and finished with a dremel using a sanding drum.

tdbru Wrote:well, I took the mags apart and looked at the parts. on the part with the stem in it that the spring attaches to, that fits on the magazine base plate, I trimmed off the stuff that stuck down . the "T" and the two wings on the back. I used a hack saw and a file. then I put this into the base plate and of course the "stem" stuck through a lot. so I marked it and trimmed it off so it was once again flush with the base plate. then I turned my attention to the follower. using a hack saw I trimmed off the lower part leaving just enough of the center slot for the top of the spring to drop into. after the hack saw I used the file to smooth things out. by shortening the follower, especially as it shortens it in the front to back motion, the follower will easily nose dive now. no big deal with a Grendel case as it's case body walls are of minimal taper. so it feeds. the 7.62x39, with it's highly tapered case, will just rotate nose down as you push on the top back of the case. so I wouldn't recommend this for those with the 7.62x39 mini howa. the next step is to take a 1" or 1.5" SHARP wood chisel and take out the two little ribs in the magazine body that limits how wide the cases can stack. I simply tapped on the back of the wood chisel with a plastic mallet a little at a time holding the wood chisel flat against the inside of the magazine body. this peeled up the little rib. when I got to the curved part up near the top I went in from the top and peeled off the rest of that little rib just by pressing with the chisel and wiggling it side to side. for those with 7.62x39 mini howa's you can probably do the rib removal and the bottom spring holder part, but I wouldn't recommend doing the follower modifications. I hope this description was sufficient. the first one took me about an hour. the 2nd one took me about 15 - 20 minutes as I had a better idea of what to do and how to do it. if you have any questions please ask.
best regards,
-tdbru