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SOC's MGI modular AR-15

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SOC's MGI modular AR-15 was created by SOC

Base Rifle - MGI modular QCB-D upper and Modular Lower.
Stock - Magpul CTR
Grip - Magpul MIAD
Trigger - Geissele Super Semi Auto - Enhanced
Gas Block - PRI Adjustable
Muzzle Break - PWS FSC

Calibers .22LR, 5.56/.223, 5.45x39, 7.63x39 with AK47 mags, 6.5 Grendel

Planning to add a 7.5" 300 BLK next once I get the SBR paperwork done.

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I really like the tool-less takedown, easy to switch calibers, easier to clean.

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Longest parts are the barrels at about 20" with gas tubes and muzzle breaks.
Easy to fit in a suitcase or backpack for discrete carry.

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I can shoot AK47 ammo right from AK47 mags.

I have a fully upgraded CMMG 22LR kit that has the bolt hold open forward assist cuts etc to duplicate normal operation for training.

Of course people want to know about return to zero.

1. Install desired caliber and shoot 5 - 10 round group at 25 yards.

2. Shoot 5 - 10 round group removing and re-installing barrel between each shot.

3. Compare targets.

I have yet to have a barrel that made groups large enough in step 2. for me to notice. I'm not shooting at 100yrds off a bench ether but I might get to that point this summer.

I keep a dope book to record sight and gas system settings for each caliber and then each load for given caliber. I record settings in MOA and gas adjustment from fully closed. That allows me to swap to a bran new optic or iron sights, zero with say 22LR at 25 yards with as many rounds as I need, than install 5.56 adjust settings on sight and fire a 3-5 round group exactly where I expect to hit. It saves on expensive and hard to find ammo.

A word of caution. Some people have had problems dealing with MGI as a company, getting parts or customer service.

My experience has been good. I sent in my old CQB-C upper because it cracked where it was machined too thin, they sent back a bran new CQB-D upper at no charge. I sent my lower in due to the buffer retaining pin damaging the buffer (I was hoping to get a new lower as I assumed the buffer retainer pin hole was in an out of spec location) they replaced the buffer and sent it back. So I would rate my experience with MGI as an A.

I bought only the stripped upper, lower, magwells and 2x buffer spring from MGI and built the rest of my rifle using top tier components, many from Armalite. My result was a rifle that has preformed to top tier standards.

Every time a new wizz-bang AR-15 or even AK based round comes out, I'm generally only a barrel and maybe a bolt away, a $200 to $300 investment that normally costs $1200 and up.

I like to say my MGI is my little B$&#h with multiple personality disorder.
The following user(s) said Thank You: jtallen83, Lizardette
10 years 10 months ago #25671

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Replied by Lizardette on topic SOC's MGI modular AR-15

Multiple personality disorder... Cute.

I'm seriously glad to see a good write up on this. Thank you.

Another question: How well do the replacement magazine wells fit, have they gotten any looser after swapping them out a few times, and if so does it make a difference in feeding?

I really want to hear about how this does shooting from a bench at 100 yards as well.
10 years 10 months ago #25676

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Replied by SOC on topic SOC's MGI modular AR-15


Magwells stay tight, there is a lot of bearing surface and the anodizing is very hard. Your going to get more ware and play between the upper and lower fit wearing first, long before there is any play in the magwell fit.

I notice the fit between the upper and lower is different depending on the magwell. None are excessive, with the AR magwell the fit feels normal with some play. With the AK magwell it is very tight and a little tricky getting the rear pin in place, my grease gun magwell is the same fit as the AR.
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10 years 10 months ago #25677

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Replied by LebbenB on topic SOC's MGI modular AR-15

You're one of the few people I've met using this system. I saw some pics of it several years ago on LF. Looked interesting. I'm really curious about the barrel - some pics and description of barrel change-out would be greatly appreciated.

Why did you decide to go with this system versus a more traditional AR?
RLTW
10 years 10 months ago #25683

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Replied by faawrenchbndr on topic SOC's MGI modular AR-15

Looks interesting, but I have never been a fan of anything modular
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10 years 10 months ago #25684

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Replied by 13fcolt on topic SOC's MGI modular AR-15

I'm curious about that barrel swap as well.

It is an interesting system. I'm not sure I could make it work for me. I have a hard enough time with extra parts growing into complete weapons. A system that relies on extra parts laying around would kill me.
ArmaLite Super SASS for sale W/ extras. PM for details.
10 years 10 months ago #25686

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Replied by OleCowboy on topic SOC's MGI modular AR-15

Not throwing rocks at anyones choice of significant others or significant guns in their lives. Like you I am not a fan, not doubt from countless encounters with 'Universal' fit parts, kits, gadgets etc. All of which means it fits and does nothing well and in most cases not even good. And trust me I have spent a ton of money on multi tasks and fit stuff to only be disappointed at the end of the day.

That said there are a few thing out there that do a excellent job. I have one on my hip right now: Leatherman Skeletool CX. www.rei.com/product/762082/leatherman-skeletool-cx-multitool Of all the multitools out there this is the only one that really works in that fashion...and I have one that weighs in at nearly a 1lb and it takes a man's hand the size of a ham to hold it. I guess it would be good if one could only find the tool you need on when you need it.

The reason why the Skeletool works is because it does not try to be everything, in fact less is more and its one of the most successful tools Leatherman has come out with.

But that is just me....and I wish all well and much success that chose a road less traveled...
10 years 10 months ago #25693

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Replied by LebbenB on topic SOC's MGI modular AR-15

"Dang it, I brought the wrong magwell!"
RLTW
10 years 10 months ago #25707

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Replied by faawrenchbndr on topic SOC's MGI modular AR-15

I agree 'Cowboy.

As long as it works for SOC, that is all that matters. I have never been a fan of multi tasker tools. I understand how some may like them though. Kinda like buying an ElCamino vs a real truck. I'll take the truck, nor a car that can do SOME of what a truck can.
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10 years 10 months ago #25708

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Replied by 13fcolt on topic SOC's MGI modular AR-15

Modularity is what brought me into AR stuff in the first place. The ease that I can build what I want, the way I want it just can't be beat.
The concept is solid, already able to change from heavy varmint rig to light tacticool carbine by pushing 2 pins and swapping uppers, I see this as expanding on that core concept with the addition of the magwells. Particularly with the 7.62x39, the only other option is finding a lower made for AK mags.

The quick change barrel is what I really like more than the rest. That alone would make for a more compact package for transport.
ArmaLite Super SASS for sale W/ extras. PM for details.
10 years 10 months ago #25709

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