7 round mag mod for the mini howa

[tdbru]

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

[Sticks]

Post the instruction thread link if you can. I can not remember were it be. I have 8 of them to do.

[tommyguns]

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

How did you do it?

[A5BLASTER]

How did you do it?

I did mine when I had it by cutting down the follower and end plate to bare min.

[tdbru]

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

[1075 tech]

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.

[A5BLASTER]

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.

That's what I did. Same steps just didn't cut the body down.

[tdbru]

1075 Tech,
yep, sounds like the same results, different methods.
-tdbru

[tommyguns]

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

Thank you so much for posting your extensive directions, you've saved an old fart a lot of time and trouble (and probably a mag or two!).

[tdbru]

since I didn't have photos, I tried my best to accurately describe what & how I made the mods. probably a classic case where "a picture is worth 1000 words"
-tdbru

[jmkhenka]

I think the reason Howa/whoever made the magazine the way it is, is to eaze manufacturing. When you sand down the follower to flush, installation becomes a bit more tricky. In the factory configuration you just drop the stuff in and close it up but when its flush it will fall out of the bottom if not aligned properly.

and yeah, now i got a 4 round flush magazine OR a 7 round full magazine. But i never have use of more then 5 (when shooting groups).

I was out hunting with a flush 2 round magazine, and the problem became apperant but now i have 4. Need to sand it down a bit more, closing on 4 rounds is a bit hard.

[Stevil]

https://youtu.be/hdFLiIcaKXg

[raamaudio]

Very cool mod, thanks for posting!

Now, who here has a .223 10 round mag to see if it fits into the mag well? If it does maybe it can be modded to work with the Grendel and still hold ten rounds, I would love to give that a try but I do not even have my rifle yet.

Rick

[tdbru]

Rick,
i think, though am not sure, that the 10rd 223 and the 5 rd Grendel are the same size. reason for 10 is the smaller diameter of the 223 vs the 6.5 Grendel. i could be wrong though.
-tdbru

[HokeyPokeyKid]

All the different caliber magazines for the Howa mini that I have seen have the same external dimensions. Only the internal dimensions change to accommodate feeding of different cartridges.

[raamaudio]

It would be very cool then if the great 7 round mods for the 5 rd 65G mag would result in ten rounds in the .223 magazine, I will just have to try it once I have the rifle, 5 round mags, etc....I know the follower is likely different but maybe there is enough material to work with and make it compatible with the 65G. (or if not, grind through it, add epoxy, shape it, good to go, I can always hope so

If that works I will make sure it is known of course but I hope somebody is ahead of me on this and just gets it done but in the end, 7 rounds is going to be nice to have as it is with the stock magazine mods.

Rick

[m796rider]

I can't believe it'd be all that hard to measure and input a 7rd modded mag body and follower into 3D CAD software and send the files off to one of the bazillion 3D printing job shops out there... Heck, I may try it along with maybe designing an extended mag to hold 10 rounds.

[raamaudio]

Go for it!
Please

[tdbru]

i took one of the 7rd Grendel mags and stuffed twelve 222 Rem cases into it. BUT, the feed lips are too far apart on the 6.5 Grendel mag and the 222 Rem just pops out. so maybe if one did the mag mod on a 10x 223 mag they would end up with 12x 223 mag.

-tdbru

[raamaudio]

That would be cool
I have Elander mags and polished the feed lips on them, work perfect no matter how many rounds I have put in them.

Using a mic and dremel it should be pretty easy to copy the 65G howa mag lip openings to the 10x223.

It would be nice if the follower just worked or needed very little effort to make it work.

Rick