Looks pretty good ! Is that your only retro ?

Is this a rifle length gas?

Nicely done! Never was a true 605 fan (believer?) in the past, but between this one and the others posted (Morg) they are growing on me.

Not my only by any means. Here are a few that started years ago.



The 605's at the top is the one you see now finished. The 605B I have still unfinished will be the sleeper.







This 605 is RLGS, some really old barrel with chrome chamber, but not a chromed bore.  Somebody buggered it up in the ban era, and welded a muzzle brake to it, and took off the bayonet lug, making it perfect for a 605.  The FSB is also de-flashed and very old. I got it recently with an SP-1 upper that had been refinished in some ugly black crap, over corrosion. I installed one of my original ejection port doors, and I have plenty for my planned builds.


Progress on my XM177E2, but I'm thinking I will have to go MLGS/longer handguards and avoid the criminals at ATF.



The sights on this 605 line up perfectly, so that TDC should be very close to mechanical zero, which is pretty rare on modern guns.

Stock is a Type D, pistol grip is a transitional bakelite/glass nylon (mottled) with "Dead Kennedy's" logo inside a circle and "B". I have others that are "DK Circle A".

Bolt Carrier came from Boywonder, and is chromed with large opening on the right side for the firing pin retaining pin. I added a modern chromed bolt to it, and standard cam pin.

Lower is NDS-XM16E1with the buffer retainer roll pin, partial fence.

I dimpled the selector and Cerakoted it Gray. I buggered the 3-prong, then saw that some people use a strap wrench, so I did that for installation and it works awesome. Need to coat the 3-prong to cover my dings that I filed off.

I'm looking forward to shooting it. I'm interested to see how the gas system runs as-is, before I consider opening it past .0935".

I'm feeling pretty similarly. Never wanted a 605 but the more I see them the more appealing they are. I'd like to see one with a 607 lower on it, anybody have a pic of that?

That's really nicely done. Congrats

p.s. has anyone ever done a 605 with the milled off FA "hump" version?

yeah when NDS had the uppers, several members have done those builds.  even a few original uppers floating around.

I'll go through the archives and look through the pics thanks wonder.

Looking good, nice start on the other builds. If you end up needing to enlarge the gas port, put a cheapo aluminum cleaning rod through the muzzle end before drilling. I did for peace of mind when enlarging the port on my 16 inch with rifle length gas when it would not fully cycle, 0.110" was the recommended size I ended up using a 7/64 drill (0.109") close enough.

Being a muscle car nut, the term "sleeper" has piqued my interest. I really like the alternative caliber retro builds we've seen here, from visiting the variants forum I know you are a Grendel enthusiast.

Those are kinda cool.  I remember Fulton Armory had GI barrels for those.  I've read that you have to open up the gas port to get them to run dependably.  The originals had cycling problems.  That's why they weren't produced in large numbers.  Is any of that true ?  It must be, I read it on the internet...

That works, too. Small plastic rod or wooden dowel may work just as well.

Looks good OP!

I've been kicking around the idea of a dissipator for the past two months but everyone tells me how unreliable they are with the rifle gas system. I really don't like the idea of the "mock" dissipator with a gas block under the hand guard, they are to front heavy, but I may just say the hell with it and move forward on it. That's why we have suppressors right?

http://www.ar15.com/forums/t_6_20/420642_AR15_16in_barrel_with_rifle_gas_system_and_suppressors_.html

It's true.

Had they invented the dissipator then and there we'd have been much better off.

The sleeper 605B is going to have a lot of internal features that are the epitome of the AR15 system, as it has evolved over the past 50 years. I already have most of the components.

I have a CLGS 5.56 heavy barrel that has already been partially re-profiled, but I have some other ideas on caliber as you mentioned. I'm looking at:

6.5 Grendel, 25 DTI, and 6mm Hagar

It will be a concealed free float tube-already have the DCM barrel nut, 6061 aluminum tube, enlarged hole handguard cap and modified handguards.

Bolt carrier is a Young's slickside, hard chromed.

I'm thinking the JP Enterprise Silent Captured Spring for recoil system.

I already had the custom non-firearm lower engraved and profiled for a 605B with 4-way fire control group. Everything on the outside will be as authentic as possible. This is more of a proof-of-concept demonstrator than anything. Most of the exciting features I haven't really mentioned yet...

Very nice. Looking forward to the updates. I myself planned my 605 as a cut-down 601, and as a BTDT similar to John Thomas's beautiful 'beater' 601 build...unfortunately, Heatnbeat did such a beautiful job on it, I haven't been able to bring myself to age it. I have to say, if you have any doubts about a 605, try one. They handle like a carbine, but feel short. Great for CQB, because your eye is on the FSB, and not much past that to catch on doorways, etc. It also has a longer sight radius, which translates to accuracy, and is easier on older eyes. I haven't sighted mine in because I need to replace the A1 aperture with an A2 - but am dying to shoot it. I have to say, the 605 looks best with a full-curve magazine IMO. Somehow what seemed at first like a graceless pig now seems purposeful and brutally efficient. This is the pic that did it for me. (turned for better view of 605)

Morg I have to agree with you completely. I've always liked the look of the 605 it mixes clean lines with a subtle brutality. I'll have to do one at some point now :(

My 605ish was a spare parts build and had I known how much I would like it I may have built it a little more correct but as it is I love it!

If you have any doubts about building one then find one to handle and/or shoot and all doubts will be removed.

The funny thing is, it's easy to say 'it's a shortened rifle' then try to imagine it by handling a rifle. That however just doesn't work. Although the ergonomics are obviously the same, it has a completely different 'feel' to it when moving around with the thing. It feels much shorter somehow than it really is. It truly is a carbine, and more somehow than just a chopped '16...it's very hard to describe, but if you try one, you'll be hooked. I like it much better than the standard length rifle. I really think building one using an M4 barrel and carbine gas would be the ultimate logic, perhaps turning down the barrel ahead of the gas block and using a .625 FSB pinned in a kino configuration.

I have a barrel already profiled for the .625" FSB for my 605B project, but the barrel still needs a weight loss plan behind the gas block journal. It's a heavy Bushmaster beast from the ban era.

It currently has the original .068" gas port, but was profiled nicely on the fore end, threaded and recessed crowned.

It needs the rest of it turned down, and I'm even thinking about dimpling to cut weight. The 605 with a standard barrel profile is lightweight, but not as lightweight as I would like it to be.

It does handle much better than a rifle without a doubt.  There was an article someone posted here a while back that was advertising the Colt CAR-15 family of weapons, of which the 605 was part of, and it had detailed descriptions of each weapon. It stated the 605 was meant to be an Infantry Leader's carbine.

If they had the presence of mind to put the gas port behind the FSB it could have been a standard rifle for all Soldiers.

I agree, and we could have skipped 50 years in overall weapon profile in many ways when you consider the SOPMOD Block II Rifle-Length Handguards with 14.5" barrels, low profile gas blocks underneath the float tube.

I also like the idea of a Mid-Length triangular handguard with CLGS, 15" barrel, and telescoping stock.  There were some MLGS prototypes in the 1960's.

This:

Just to show the color match of Cerakote with an NDS-XM16E1 lower anodized in "Colt Grey".

Except that dissipator MEANS sights at rifle distance, gas block at carbine and hidden under the handguards.  Having the gas-port at the sights makes it a mock, not the other way around.

Then why do the two dissipater barrels (listed as such) I bought from two different companies have rifle length gas systems?

Because they didn't do their research and Bushmaster failed to defend their trademark.

Regardless of what people are marketing today, it's what it originally was.

Yes, I remember the first mentioning of the term "Dissipator" in Bushmaster marketing products in the early 1990's. If someone did it before then, I can't say that I am aware of it.

They were 16" barrel, CLGS, under A2 handguards like this, but they had an older after-market telestock on that version.