[peaceful_guy]

A buddy and I want to put an Ultimak replacement gas tube and rail on his Draco pistol. To do so, we need to cut down the Ultimak M1-B.

http://primaryarms.com/product.sc?pr...&categoryId=37

We made the cut easily, but it now needs to be hollowed out. After burning through two Dremel grinding wheels, I am wondering if any of you have any suggestions for grinding out the Ultimak.

Here is our progress after burning through both of my Dremel #8193 grinding stones, about 10 minutes of total grinding.



Does anyone out there have any suggestions or experience on hollowing out a piece of aluminum? I am neither the handiest nor brightest guy in the world so maybe I am missing an obvious solution.

[1985 4Runner]

No advice, just tagging for future reference. Good luck.

What optic are you planning on using?

[sns3guppy]

Those look like grinding stones loaded up with, and plugged by aluminum. Are you grinding aluminum?

Stones are the wrong surfaces to do the work you are trying to do.

Aluminum will only clog the stones and ruin them, and will do very little work.

[peaceful_guy]

Originally Posted by sns3guppy

Those look like grinding stones loaded up with, and plugged by aluminum. Are you grinding aluminum?

Stones are the wrong surfaces to do the work you are trying to do.

Aluminum will only clog the stones and ruin them, and will do very little work.

Well I guess that is exactly the piece of advice I needed!

[peaceful_guy]

Never mind, I'm an idiot. I just described the problem to a friend who immediately replied "use a drill bit."

So, use the dremel to cut the tube, then a drill bit to hollow it out.

[mammynun]

I considered a large drill bit, but was concerned that I wouldn't have enough "lip" on the Ultimak to fully seat, or in my ability to keep it centered. Here's what I did.
http://www.ar15.com/forums/topic.html?b=4&f=98&t=126188

I found a 2-pack of "step drills" at Habor Freight (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96275 )to re-bevel the front end of the Ultimak (I also used the M1-B). I put the Primary Arms Micro Gen 1 on it and it's got over 2k with no problems.

If I remember correctly, the biggest diameter I used was 11/16", but it might have been 3/4".

[peaceful_guy]

Thanks for the referral to Harbor Freight, order placed.

[CnRnut]

You might try what is called a "unibit",or step bite.
They have an @ 1/8" "shoulder" in between sizes. This will do the trick.


http://www.recordtool.com/irwin/cons...t/unibit.jhtml

[Quiet]

Good luck with your project.



I opted for the Midwest Industries AK rail for mounting a Primary Arms Micro Dot to my Draco pistol.

[ninjazx6r]

Can you still use the iron sights with your midwest rail with out the red dot on it?

[peaceful_guy]

I just do not want to go through the hassle of SBR, and want to stay completely aboveboard. So it will get an optic, but will not get vertical grip.

[Quiet]

Originally Posted by ninjazx6r

Can you still use the iron sights with your midwest rail with out the red dot on it?

Yes. I can take the red dot off and can still use the iron sights.

[Quiet]

Originally Posted by peaceful_guy

I was going to go with the UTG quad rail, but decided to put that on my WASR. Part of the calculation was, I have some vertical foregrips laying around and did not want to veer into SBR territory. I just do not want to go through the hassle of SBR, and want to stay completely aboveboard. So my dracos will get optics, but will not get vertical grips. I sure wish the law was different!

If you put a forward grip on a handgun, it makes it an AOW not a SBR.

I went with the rail, because I'm contemplating making it into an AOW.
(I was inspired by this CA legal AOW AK pistol)

[peaceful_guy]

Originally Posted by Quiet

If you put a forward grip on a handgun, it makes it an AOW not a SBR.

I went with the rail, because I'm contemplating making it into an AOW.
(I was inspired by this CA legal AOW AK pistol)

Yeah, I realize the foregrip only makes it AOW but it seems like AOW is just as big a hassle as SBR.