My new 10mm DI

[Teninator]

So I finally got my 10mm DI together. The upper from Macon Armory took like 9 months, but it's finally mated with an Angstadt Arms lower. 

It eats (almost) everything I put into it. FMJ handloads, factory ammo, and even some cast boolits. The only issue involved some handloads I had made with AA #9 stovepiping (165gr FMJ 14.7gr AA #9). I'm thinking maybe the slower burn rate is messing with the timing. Other than that, it eats everything. I am having an issue with the last round bolt hold open, but I think that's a part issue.



Yes, I live in a non-free state, so please excuse the fin grip.








Looking forward to shooting some of my cheap powdercoated rounds through it.

[sqlbullet]

Looks nice.

Word of caution...Plain base cast bullets and gas systems don't play nice together.  Powder coat or gas check should be fine.

[Teninator]

Looks nice.

Word of caution...Plain base cast bullets and gas systems don't play nice together.  Powder coat or gas check should be fine.

Thanks. Impatiently awaiting my gas check maker die(s). The lubed cast boolits I sent had gas checks.

[sqlbullet]

I tried plain base 30 cal in my M1 Garand hoping (stupidly) to save a penny or two more per shot.  After 1 clip the op rod wouldn't cycle correctly.  I was very concerned that I had bent it, but it turned out to just be lead build up in the gas cylinder.  That was enough to convince me.

Gas checks work great.  I have read that powder coat does great too, but I consider a bit of copper on the base good insurance for guns that are nearly 80 years old.

[Teninator]

I tried plain base 30 cal in my M1 Garand hoping (stupidly) to save a penny or two more per shot.  After 1 clip the op rod wouldn't cycle correctly.  I was very concerned that I had bent it, but it turned out to just be lead build up in the gas cylinder.  That was enough to convince me.

Gas checks work great.  I have read that powder coat does great too, but I consider a bit of copper on the base good insurance for guns that are nearly 80 years old.

Yeah that seems to be the big fear with Desert Eagles (I have one), that the cylinder will get clogged, a very difficult fix in a DE. But there's a guy on YouTube who shoots powder coated 50AE without issue (he gas checks):

https://www.youtube.com/watch?v=Zepp97UwCSs

I have a 50 gas check die coming, along with my 10mm one. Better safe than sorry!

[sqlbullet]

Love the full.lead.taco's channel.  His tastes and mine run very similar.

I also have a DE and have avoided cast bullets in 50 AE.  I have conversion barrels for 44 mag and 429 DE so I will probably run powder coat for those when I get to them.

[redial]

Intriguing rig! If possible, could you post a photo of the bolt/bolt carrier. Just curious about its design.

Thanks!

Mark

[sqlbullet]

Not the OP, but it is a DI BCG.  It is actually probably just a 6.8 SPC BCG.  Case head diameter is only .003" different than 10mm.  6.5 Grendel probably would work too.

[redial]

Ah ha! Thanks, sqlbullet. What I was leading up to was to ask what the engineering obstacles might be in such an outfit. The BCG matches up conveniently for this application but I'm sure there are other considerations of which I'm not aware. It seems that all the wizardry would be in fab'ing a 10mm barrel with the standard AR DI features. Could this just drop on a suitable (pistol magazine) lower?

Mark

[sqlbullet]

Yes, this upper should run on any AR lower with a suitable magazine system.

I am not a novice, or an expert, at AR building.  I have built enough to know that it's about pressure and dwell.  I would guess they use a pistol length gas system with a gas port in the .089-.096" range.  The proximity of the gas port to the chamber should give it the best shot at pressure, and a healthy port size gives it enough volume to do some work.

[Somachef]

You've done a great job! The gun looks amazing. I thought about buying myself the same model last year, but I exceeded my expenses, so I could not allocate money for a new weapon. At the moment I am using Beretta 486 Parallelo. While maintaining the traditional quality of the finish and the style, Beretta offers us a cold-forged block of trunks soldered using Triblock technology, ensuring high rigidity of the connection. I bought this gun three years ago at https://walkeroutdoors.net/product/bergara-bxr-22lr-semi-auto/, and I'm still happy.

[Kenk]

Welcome Somachef, cool .22 by the way

[redial]

I have the same Bergara with a standard barrel. Suppressed, it's a gopher killing machine and is everything the 10/22 should have been initially.

Mark

[Teninator]

Just an update. After working on some things with Rudy at Macon Armory, mostly using a heavier buffer, and Rudy expanding the ejection port a bit, this thing eats (and poops out) anything and everything. I'm going to get the 45 ACP DI upper as well soon.

Currently with a Vortex Spitfire 3X Prism optic, although I am really liking the smaller and lighter Primary Arms MicroPrism on my Sig MPX.

Also swapped in a "Gas Buster" charging handle because I was getting some gas in the face. Solved that problem.



Some chrono info:

165gr FMJ 14.7 Accurate #9 1504-1508
180gr FMJ 10.9 Blue Dot 1406-1424 1 @ 1447.
187gr cast/PC 9.9gr Blue Dot 1368-1343 (I'm sure I can go hotter, but flying blind due to the weird weight).

Some pics of my cast and powdercoated 187gr boolits:



The aluminum are handmade from Matteson's checkmaker die (.011 and .014 flashing). The copper are Sage's checks.



The one on the far right is an old school Lee 175gr lubed boolit I first used for my 40 S&W, smokey AF! Fun to shoot out of my Glock 29 with comp barrel. 

[Kenk]

Nice looken boolit / PC job 😀