Titanium AR-15 complete.

[Kingjamez]

I took off of work the week before Oct. 1 to finish the machining on my last "pre-ban" AR-15. Since then I've been finishing up the detail work: sanding, blasting, fitting tight parts, etc. It is now pretty much done, the jury is still out on the finish though. It's anodized, but with Ti you only have a limited selection of available colors based on the voltage used. To get anything near FDE, I had to use a very low voltage, which yields a thin anodization layer. We'll see how it holds up, it seems to be a smudge magnet right now. I may end up ceracoating it.

Specs:
Home made from a block of Grade 5 6AL-4V titanium (not the easy to machine CP Ti)
Geissele SD3G trigger
KNS anti-rotation pins.
EBRv2 Bolt release (arrives and will be installed Thursday)
JP silent captured recoil spring.

Upper variable, but currently wearing an 18" DPMS barrel, YHM rail, a YHM Ti Phantom Suppressor, and a Primary Arms ACSS 6x scope.

I don't recall ever seeing another 6AL-4V AR-15. I saw an AR308 in Ti, but that's all I could find. Anybody else seen one before?

-Jim

 

[Kingjamez]

iPad won't let me put more than one photo:

 

[lowoncash]

Nice rifle, but where's the foot?

 

[Minuteman]

Sweet looking AR, great project, thanks for sharing.

 

[armed ferret]

why not just anodize it thicker, and then cerakote to get the desired color?

looks nice though. what's the weight savings over a standard forged aluminium lower?

 

[Kingjamez]

why not just anodize it thicker, and then cerakote to get the desired color?

looks nice though. what's the weight savings over a standard forged aluminium lower?

That's not a bad idea. If I anodize it at 100 volts it will be green, but have nice, thick layer on the order of hundreds of times thicker than it is now.

I didn't change the dimensions of the lower to account for the much stronger titanium. To that end, since titanium is heavier than aluminum per unit volume, the lower actually weighs a good bit more than a standard lower. Ti is really unneeded in a lower. I only did it because it made for a fun (albeit expensive) project.

-Jim

 

[aray]

Titanium. Wow. Nice looking gun.

BTW, what optic have you got up on there?

 

[FrankOceanXray]

Well done.

 

[ObsceneJesster]

Cool idea. You might be the only guy in MD to have a Titanium lower.

Maybe next time, you can go for the heaviest receiver in MD and use Tungsten.

 

[Verbotene]

TiN.

...What? Would look pimp-as-hell. Just saying.


Very nice looking gun.

 

[Kingjamez]

Titanium. Wow. Nice looking gun.

BTW, what optic have you got up on there?

Thanks! It's a Primary Arms 6x fixed scope on a PA deluxe mount.

Cool idea. You might be the only guy in MD to have a Titanium lower.

Maybe next time, you can go for the heaviest receiver in MD and use Tungsten.

I like the Tugsten idea! I have no idea how it is to machine... May have to look into that:-)

TiN.

...What? Would look pimp-as-hell. Just saying.


Very nice looking gun.

I actually looked at TiN coating, but oh man how ugly a bright gold gun would be!
AlTiN would be pretty cool though.... Hmmmm...
-Jim

 

[aquaman]

You should make the upper in Ti

 

[ken792]

Wow, how much did that block of Ti cost?

 

[armed ferret]

Wow, how much did that block of Ti cost?

"About a hundred dollars...."

--Morgan Freeman, "Days of Thunder"

 

[Pinecone]

I thought that Gieselle recommends NOT using the anti rotation pins with their triggers???

 

[BenL]

Very cool.

 

[mvee]

Awesome!!!
What type of take down pins are those?

 

[Kingjamez]

I thought that Gieselle recommends NOT using the anti rotation pins with their triggers???

That is certainly true for the High Speed national match trigger. It uses a different groove profile on the hammer retaining clips. The SD3G uses a standard retention groove, so won't be damaged by a non-Geissele hammer pin. The other reason claimed that you can't use KNS pins is that Geissele pins are supposedly oversized for a tight fit in the lower. Before installing the pins, I mic'd them and the KNS pins were as close to identical in diameter as I could measure. They were within ten thousandths of an inch or so. Certainly better than the accuracy in which I could make that hole round.

So, the Geissele pins are very good, very round, very consistent. So are the KNS pins. The KNS pins aren't better, but they are cooler. Just like the titanium lower, it's not better than aluminum, but it is cooler.

Awesome!!!
What type of take down pins are those?

They are KNS push button pins, I used them because the don't require the detent pin to be installed to stay put. I've had bad luck drilling 1+ inch deep 3/32 inch holes in Ti, I've broken drill bits in the holes in the past and the bits are extremely difficult to remove.

I was so close to having this lower done, I didn't want to risk ruining it while drilling those holes, so I just didn't drill them. I really don't like the push button take down pins, they are a pain, but I also don't want to ruin this receiver that I can't replace thanks to SB281.

-Jim

 

[BuildnBurn]

Beautiful job.

How did you cut the mag well.....broach, edm, shaper?

 

[Kingjamez]

Beautiful job.

How did you cut the mag well.....broach, edm, shaper?

Yeah, that was hard. I originally lined up a guy to EDM the mag well. In fact I wouldn't have started this project without getting him on board first. However, when I was ready to send him the lower for EDM'ing, he went completely silent. No email responses and I couldn't find any one who could get in touch with him. With Oct 1st looming, I decided to just mill it out.

I used an extra long 3/8" end mill to mill down to 2.25", then flipped it over to finish the bottom flare. After hogging most of the material out, I used a 1/8" end mill to plunge the corners. I then used a file and a healthy amount of Dykem to square up the corners. It took a lot of elbow grease, but came out pretty well. Since I was filing, I was able to exactly fit both Gen2 and Gen3 Magpul magazines. The different gens index at different points and this lower perfectly indexes both while still working with GI mags.

-Jim