Buckeye .45's Mock Dissipator Build Thread *Now W/ upper info

[buckeye .45]

I have been amassing parts for my latest AR project, a mock dissipator build, over the past few months. My upper/BCG should be here later this week from PSA, so I went ahead and put my lower together today.

I guess first I should explain the what and why of a mock dissipator. A few decades ago, when the carbine options for the M-16/AR-15 family were much more limited, people tried to find ways to shorten their full sized rifles down. One attempt at doing so was to make a dissipator, which involved taking a full length rifle, and chopping off the barrel right in front of the front sight post. This shortened the rifle by about 4 inches, but caused havoc as far as reliability and functioning. Enough gas wouldn't make it back to the BCG, because the bullet was leaving the barrel right after it passed under the ports for the gas tube. So dissipator rifles often would not function.

Fast forward to today, and several companies, including Palmetto State Armory, are offering "mock dissipator" uppers. These uppers generally have a mid length gas system with a low-profile gas block, as well as a front sight assembly out at the end of the barrel, the same distance from the receiver as it would be if there was a rifle length gas system. So these uppers are actually a 16.5" mid length upper, with a front sight post that serves as just a sight/attachment point for handguards, not as a part of the gas system.

At this point, someone is probably going, well, why not just buy a normal mid-length carbine? There are two things I generally don't like about a lot of AR carbines as it relates to my shooting style. First, they have a rather short sight radius. Generally speaking, the longer the sight radius, the better. A Mock dissipator solves that issue by having the front sight at almost the end of the barrel, effectively giving an extra few inches over a normal mid-length or carbine length system rifle. I like optics, I think that they are one of the biggest leaps in individual kit for infantryman in the past 50 years. But, I am also a firm believer in knowing how to shoot with irons, and having back-up irons on my rifle. Because of this, I want a rifle with the longest sight radius possible, while still maintaining the short length of a carbine. Second, I like to run my VFG and light pretty far out on a rail. Having a light far out there eliminates any light shadow from the barrel, and the VFG being further out helps with control during rapid fire. The ability to use rifle length handguards and rails means that I can place these as far out on the rifle as possible, right up by the muzzle.

And for those who are asking "why not just get a full sized AR-15?" Because I wand to maintain the lighter weight and maneuverability of a carbine. It is hard to work indoors with a rifle with a 20" barrel, not impossible, but not as easy as it could be. Same thing for getting into and out of vehicles.

So, now to the nitty gritty of the lower, I will talk more about the upper and it's specs when it gets here later this week.

IMG_02232.jpg

The lower itself is an Aero Precision lower. It is marked for multiple calibers, and has pictograms instead of the words "safe" and "fire." Other than that it is the same as most other metal AR lowers, nothing special.

I went with one of PSA's MOE lower build kits. I couldn't find any flaws with any of the parts, and they were all included as advertised. It came with a mil-spec buffer tube and Magpul MOE stock, trigger guard, and MOE grip. As well as Palmetto State Armory's standard weight buffer.

Other add ons that I decided to add: A Noveske short throw ambi safety lever. I don't have any experience with Ambi-safeties on AR's but I wanted to give one a try. If I need to change it to the more traditional style, that wouldn't be hard to do.

Magpul ASAP sling plate: Even though I am starting to like my Vickers VTAC more and more, I still like having a sling plate on my rifles for single points.

Putting it all together took me just a little over an hour, taking my time and paying attention to what I was doing, while referencing ITS tactical's build guide. I didn't run into any significant issues, building an AR lower really isn't difficult as long as you take your time.

Here is the finished lower:

IMG_02242.jpg

And the ambi lever on the other side:

IMG_0227.jpg

[DefensiveCarry.com]

[Drgnfly]

Very nice. Still waiting from my LPK from PSA :( Still no "Shipped" email

[rocky]

Looks like a nice start on your project. Keep us up to date as you get parts in and assembled. I was planning on a mock dissy from PSA , however It was always out of stock and I wanted to finish my girlfriends AR. I ended up getting a mid length upper instead.

[buckeye .45]

Looks like a nice start on your project. Keep us up to date as you get parts in and assembled. I was planning on a mock dissy from PSA , however It was always out of stock and I wanted to finish my girlfriends AR. I ended up getting a mid length upper instead.

They do always seem to be out of stock. I had been wanting to buy a whole rifle build kit with one for a while, but it seemed whenever I had money, they didn't have any in stock, and vice verse.

So instead I have just started acquiring parts to do builds when I find good deals. The MOE build kit was on sale for $110 when I bought it, which I though was a pretty good deal, so I picked some up, and waited on the rest.

This way I can have multiple builds going on at once, and don't need to spend all the cash up front for rifle build kit.

A few other companies sell mock dissy uppers, Delton comes to mind.

[rocky]

Yeah , the $50 stripped lower got me started. I just kept looking for deals or buying stuff as I had a bit extra. Dang PSA has so many decent deals I could go broke if I bought them all.

[buckeye .45]

Yeah , the $50 stripped lower got me started. I just kept looking for deals or buying stuff as I had a bit extra. Dang PSA has so many decent deals I could go broke if I bought them all.

They do have a fair number of good deals. If everything checks out on the Mock Dissy upper, I will probably order a full length rifle upper from them when they are in stock.
I am curious to see about their BCG too.

[buckeye .45]

Today the brown truck of happiness dropped off the package with my upper and BCG. So, now I have a complete rifle. Here are the specs from the PSA website:

Barrel length 16"
Mil-spec barrel steel
5.56 Nato Chamber
Chrome-lined bore and chamber
1 in 7" twist
Special A2 style profile barrel
.750" gas block diameter
MPI & HPT barrel
M4 feedramps
Forged upper
T-marks

And for the BCG:

Milspec MPI Carpenter No. 158® steel bolt
Chrome Lined Carrier (AUTO)
Chrome Lined Gas Key
Gas Key Hardened to USGI Specifications
Gas Key Grade 8 Hardened Fasteners
Gas Key Staked Per Mil-Spec
Tool Steel Extractor
Extractor Spring
Black Extractor Insert

BCG pictures:

IMG_02332.jpgIMG_02312.jpgIMG_02292.jpg

[buckeye .45]

Gas system:

IMG_02342.jpg

Complete rifle:

IMG_02372.jpg

Admittedly, I think it looks kind of goofy with traditional A2 style handguards on it like the PSA website has. I think that the MOE handguards give it a much better look. Other additions I am trying out are the MOE rear sight, and an extended charging handle latch (PSA's version). The Grip Pod I have had for a while.

The rifle as it sits has a 20.5" sight radius, which is much better than the average 16" M4gery.

Now I just need to get to the range and see how it shoots.

EDIT: My Bushmaster M4gery has about a 14.5" sight radius.

[SIXTO]

Looks good!

[buckeye .45]

Man, no love for the Dissy. I think I am going to change the thread title to "Word association thread part deux"

[SIXTO]

There never really is; I don't think many understand just what it is and why it's a tad better than the norm.

[buckeye .45]

There never really is; I don't think many understand just what it is and why it's a tad better than the norm.

Which really is unfortunate, because it offers many of the benefits of both a full sized rifle, as well as a carbine, and eliminates many of the downfalls of both as well.

I am not sure how long this MOE rear sight is gonna last. Probably gonna be a few months before I get an optic on it, so its going to just be irons for a bit.

I think as a pure BUIS, the MOE would be okay, so I might swap it for the stand-alone non-folding Larue that I have on my Bushmaster, since that one is running an optic already.

But, I need to shoot it before I make that choice. I'd like to find a BUIS that offers both windage and elevation adjustments.

[OD*]

Lookin' good.

[buckeye .45]

Lookin' good.

Thanks OD*

Unfortunately Colt doesn't make a mock dissy, so they were out of the running this go round.

[Doodle]

Very cool, I agree Moe furniture was the way to go.