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Anyone build a dissipator style upper?

Pinned and welded the barrel yesterday and blued it last night. Also chopped off the sling swivel from the gas block since I don’t intend to use it. A Fulton armory slick side carry handle a1 upper should be showing up today.
 
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So this seemed to work just fine with the rifle gas and jp enterprise carbine buffer setup. No issues at all cycling. The 1 and only issue I had was the fancy dust cover I put on touches the fancy ambi bolt release just enough that on an empty mag the bolt doesn’t lock open. I took the dust cover off, I’m not crawling through mud with it, I also switched the fancy mag release button for a standard one. Recoil seems fairly light but it is loud haha. I zeroed it at 36 yards.

I still have a few things to gather for the fde lower I have coming, and I ordered a scale to weigh these on.

But excluding most likely that red dot, my modernized lightweight 605ish thing is complete. Final configuration is:

Upper:
Brownells 605 barrel with faxon slim flash hider
Fulton armory 604 slick side carry handle upper
Aero atlas s one 12 inch hand guard
geissele super charging handle
pretty sure I put a psa bcg in it

Lower:
ke arms kp15/ slt 2 trigger/ ambi safety
norgon ambi mag release
aero pdq ambi bolt release
jp enterprise carbine buffer
Grov tec threaded qd sling mounts

I don’t know yet if I will put a dust cover back on it, and I will probably get some trapdoor butt plates to take advantage of the hole in the stock. As for the dust cover, I crudely cut off the tabs for it on my aero slick side upper, but it was pretty much one of the cheapest pieces I have, and I intend to end up with a fde slick side upper anyways. Again, my lowers will essentially be identical, but the other upper will be even lighter.

On a side note, anyone have both of the vortex magnifiers? I’m curious if the currently $300 G30 is worth the extra $100 over the $200 VMX-3T. I don’t care about the qd mounts, I’m more interested in clarity and function and maybe how the flip out of the way gizmo works. It will most likely be staying where I put it.
 
Why rifle length gas on a 15" or thereabouts barrel? I just see so many reasons to go midlength with a threaded 16" since it isn't a strict clone build.
Also kinda confused by the dot mounted to the handguard, but I suppose they're solid enough.

I really hate to sound like such a negative nancy
 
Reason for rifle length gas vs a midlength gas was I wanted the dissipator look but not a fake gas block. It’s a 15.5 barrel, so had to pin and weld flash hider, and since I wanted free float, it needed to be a slim one so I could still take it apart if need/want to. As for the red dot, well it was on the other upper, which I needed to pull the hand guard from, so I took the dot as well. I just wanted to see how it would work there, and it seemed fine. It might stay, it might not. I do like that I have an easy spot to put one.

I had a vision in my head, and I couldn’t find where anyone had done a modernized 605, pretty much everything I could find was clones, or maybe slight variations, but couldn’t find anyone who had done what I was thinking, so I did it. Reason for a carry handle was I have several flat tops, and wanted a carry handle. Reason for a1 carry handle was no one makes an a2 fixed carry handle in a slick side upper, plus it’s an a1 front sight. Reason for ambi stuff is lefty’s will be touching it, and the only ambi gizmo that’s doesn’t really benefit a righty is the mag release. The charging handle, safety, and especially the bolt release are all nice.

Basically, I wanted something that isn’t like all the others. My main concern was that it doesn’t have a rifle buffer setup and I wasn’t sure how that would play into things, but it worked.
 
I do get the entire "this is how I want it" build. I can't say, yet, that I fully appreciate the lines of that KE Arms lower coupled with the A1 upper (but that is my solely my issue).

Here's my latest build (kinda sorta a modernized SP1) mostly because I wanted to properly drill, ream and pin an A2 FSB which would accept a bayonet like my SP1 (who the fawk knows why I wanted to do this???). However, the downside is that the FSB screws up the image for my Trijicon. Feel free to bag on it in turn. :))
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Did you use a jig for the FSB?

I dont have one and came up with a "cheat". I drill the bottom of the bayo lug for a small set screw. Slip it over the end of the barrel. Chuck up the barrel in my lathe. Use a fine point in the tool holder and index off the gas hole, lock the spindle so it wont rotate.. Confirm that the gas hole and receiver pin are aligned. Slip the FSB into place and align off the sight post. Tighten the set screw, drill and ream the rear pin. Then remove set screw and drill ream front pin.

It has worked so far, but is a bit of a time consumer
 
Did you use a jig for the FSB?

I dont have one and came up with a "cheat". I drill the bottom of the bayo lug for a small set screw. Slip it over the end of the barrel. Chuck up the barrel in my lathe. Use a fine point in the tool holder and index off the gas hole, lock the spindle so it wont rotate.. Confirm that the gas hole and receiver pin are aligned. Slip the FSB into place and align off the sight post. Tighten the set screw, drill and ream the rear pin. Then remove set screw and drill ream front pin.

It has worked so far, but is a bit of a time consumer

No jig and my methodology is not as sophisticated as yours. I'll outline them for the benefit of others:

Install "raw" barrel into the upper and lightly tighten barrel nut.
Install rear sight, insuring that it is adjusted to center.
Install upper on lower.
Using a laser bore sighter (laserlyte IIRC) time the FSB.
Using a 3" + stainless steel hose clamp (such as used for an automotive heater hose) tighten the FSB with the clamp OVER the gas "strut" (where the gas tube gets pinned) and UNDER the barrel BETWEEN the lugs of the FSB. Tighten with a nut driver till you can't turn the clamp screw any more. The FSB is now firmly secured where it should be.
Remove the barrel from the upper.
Using a couple pieces of scrap wood and washers, as shims, I square the bottom flat edges of the FSB with the drill bit (in the drill press) and then run a 2" wood screw with a fender washer into the scrap wood right beneath the top of the FSB to secure everything.
Center punch where the pins are to go and drill (drill size was the size of the end of the reamer, I don't remember the exact size).
Ream till the taper pins go a little more than halfway with no effort.
Smash the taper pins home.
Done.
 
Reason for rifle length gas vs a midlength gas was I wanted the dissipator look but not a fake gas block.
Reason for a carry handle was I have several flat tops, and wanted a carry handle. Reason for a1 carry handle was no one makes an a2 fixed carry handle in a slick side upper
I guess I think of it like an AK, there's a gas block, and a front sight base out front, neither is "fake" :P

Don't need no justification for an A1/earlier upper, they're the only ARs that look real good (and the simple sights are a bonus). A2 has too much shit going on and flat tops just never look right.
 
My scale came yesterday. With the red dot, but without the sling and rubber mlok covers, it weighs 6.01 pounds. I’m happy with that.
 
Did you use a jig for the FSB?

I dont have one and came up with a "cheat". I drill the bottom of the bayo lug for a small set screw. Slip it over the end of the barrel. Chuck up the barrel in my lathe. Use a fine point in the tool holder and index off the gas hole, lock the spindle so it wont rotate.. Confirm that the gas hole and receiver pin are aligned. Slip the FSB into place and align off the sight post. Tighten the set screw, drill and ream the rear pin. Then remove set screw and drill ream front pin.

It has worked so far, but is a bit of a time consumer


Same concept as what I’m planning to do, but it can be simplified by choosing a few parts more carefully. The 0.625” FSB I ordered from BCM came pre drilled through the sling swivel. I’m assuming that’s directly centered over the gas port but I need to look at it again.

Many of the quality barrel manufacturers place a dimple in the bottom of the barrels right under the gas port for set screw gas blocks to grab. Hopefully I can just tap the existing hole, tighten the set screw into the dimple, and then drill/pin.
 
Using a 3" + stainless steel hose clamp (such as used for an automotive heater hose) tighten the FSB with the clamp OVER the gas "strut" (where the gas tube gets pinned) and UNDER the barrel BETWEEN the lugs of the FSB. Tighten with a nut driver till you can't turn the clamp screw any more. The FSB is now firmly secured where it should be.

That is a very interesting method.
 
Same concept as what I’m planning to do, but it can be simplified by choosing a few parts more carefully. The 0.625” FSB I ordered from BCM came pre drilled through the sling swivel. I’m assuming that’s directly centered over the gas port but I need to look at it again.

Many of the quality barrel manufacturers place a dimple in the bottom of the barrels right under the gas port for set screw gas blocks to grab. Hopefully I can just tap the existing hole, tighten the set screw into the dimple, and then drill/pin.

Yes, the hole under the sling swivel aligns with the gas port, its how the port in the FSB is drilled. Thats the hole to tap for a set screw. (been a couple years since I installed an A2 FSB :) )

I have a couple WOA barrels for some builds, no dimples :(. But with the barrel in the lathe I should be able to locate the spot and drill my own dimple for the set screw.
 
Yes, the hole under the sling swivel aligns with the gas port, its how the port in the FSB is drilled. Thats the hole to tap for a set screw. (been a couple years since I installed an A2 FSB :) )

I have a couple WOA barrels for some builds, no dimples :(. But with the barrel in the lathe I should be able to locate the spot and drill my own dimple for the set screw.

Makes sense on the hole, IIRC my FN barreled one had no hole on the bottom of the FSB though.
 
From what’s i was seeing, aloharover is correct about how the hole is drilled. I currently have my 14.5 barrel apart and need to drill a dimple for the set screw.
 
My carbon fiber handguard showed up yesterday. Very nice. This upper is aero slick side, faxon 14.5 midlength pencil barrel, faxon 13 inch handguard, and I swapped the same bcg and charging handle.


Here is more accurate weights:

Carbon fiber one complete but with no sights: 4.796
605 one complete without red dot or mlok covers: 5.734
Carbon fiber one with red dot: 5.126
and I slightly misremembered the other day, 605 one with dot and mlok covers: 6.192
and just for fun.... a basically original wood stocked 10/22 : 5.166
 
Stucky, I picked up 1 of the ke arms lowers.
what all did you have to do to get it up and running?

Are you happy with the balance?
Definitely turned out light.

Not sure what upper I want to build for it, but want it to be light and handy.
 
I drilled the hole for the safety spring all the way through with a .120 drill bit, tapped the bottom to 8-32 and used a set screw to hold it in. Worked fine except I had my drill bit at the end of the chuck because it wasn’t long enough and the grip is in the way when using the tap. But you can put as much or as little tension on the spring as you want. This is assuming yours did not come with their modified safety selector. At first they were drilling a hole in the selectors so you could push the detent and spring down and push it out from the side, but they quickly changed that to cutting them with an angle so you can put the selector in the middle and push it out. Mine didn’t come with either and I already had their ambi safety stuff.

I filed and dremeled the slot for the pdq lever and tapped the holes for the qd sling mounts. I do not recall exactly what size the Dremel bit was, if you are doing a pdq lever, I’ll find out, but I just watched a YouTube video and got what the guy said. Sling mounts are grov tec threaded qd cups, 9/16x18 tap. If you want qd mounts on both sides get the grov tec ones, the ke arms or magpul ones I believe you’ll only be able to do one side or the other since they use a bolt and nut to hold it in, so no room on other side for another cup. I did not use the roll pin that holds in the buffer retainer or the spring and plunger because I used the jp enterprise buffer setup. The only other non standard piece is the longer trigger pin but those should come with the lower.

I do not have Instagram, but ke arms has been posting a bunch of stuff there. There is also a thread on ar forum where they talked about drilling it for the safety spring/detent.

On a side note, I ordered another ke arms slt 2 trigger and ambi safety, holosun hs503cu (solar panel, circle with dot reticle) and vortex micro 3x magnifier, all for the tan lower/light weight upper. I want both lowers to feel exactly the same.
 
https://www.ar15.com/forums/Industry...296126/?page=1

I don't understand how posts are numbers on that forum, but there are currently 7 pages for me, and the safety info is on page 3.

edit: as far as balance, to me it seems fine. The 605ish upper is a little more front heavy than the carbon fiber one, but my psa uppers with heavier not free floated barrels make them feel so absurdly front heavy compared to the other 2. I would at a minimum keep weight in mind when picking a barrel and handguard.

edit 2: caryw, is that a 16 inch barrel and is it rifle length gas or carbine/midlength? Looks good.
 
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Thanks for the extra info. Was exactly what I wanted to know.

Probably won't go ambi on any of the controls.
Not too sure what I want to run for barrel and handguard. Definitely want to keep it short and light.
Will probably go with a 14.5" bbl with pinned and welded brake.

Will probably wait until things are back in stock to order a lot of things for the upper.
 
I got the red dot and magnifier last week. I decided to get the vortex micro 3x based on weight and the mount vs the older version they have. I had read that the mount on the older one was not very good. Well if anyone is wondering, the micro 3x mount is kinda chincy too. If I put it too far back, the qd mount lever is in the way of the charging handle in the flip to right configuration. So I have it forward a little more than I would like but it’s fine and usable. However..... I can center the dot, but it does not stay centered. After a bunch of reading and messing with it, I’m almost certain it’s the mount. If I lock the bolt to rear and release it, the dot moves off center, if I flip it back and forth a bunch, the dot moves off center, if I release the qd lever and re snap it, the dot moves off center. I didn’t notice it shift while shooting, but did notice when I got home that it was off center. Pretty disappointing in my opinion for 300$. The actual magnifier looks great though, nice and clear.

I found a forum where someone else had the same issue and a vortex rep told them to push the red dot and magnifier forward against the picatinny lugs. Maybe this will help, but I think it is a combo of play in the pivot and the qd mount not going back to exactly the same spot. I ordered a larue mount that is supposed to be a lot better, and for what that costs it better be!

I have only ever had hands on one other magnifier, and it was a cheapy that we couldn’t get to focus, so my experience is limited here. The holosun hs503cu is great. I have 0 complaints about that.


Also just for funzies i weighed my previously favorite upper, a psa midlength 16 inch with a light and magpul sl handguard with iron sights. Just that upper with no lower weighs 5.6 pounds. The complete lightweight one with red dot, magnifier and magpul bipod was 6.6 pounds, 5.9 without bipod.
 
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In that pic, the sling mounts aren’t threaded in fully (didn’t have correct size Allen wrench at home), and the upper is still going to get swapped to a fde slick side aero if they ever come off back order. Also, I didn’t have to do the safety detent mod, since the one I was sent has the notch cut in it so you can push it out. However, I didn’t see this until after I drilled and tapped the hole. I will probably eventually get a nice non magpul sling, but this is pretty close to finished.

edit: also I forgot about the larue magnifier mount. Back ordered. I don’t know what I did, maybe I just tightened it up better, but the magnifier seems to be staying centered now.
 
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Turned out nice and light for you. I agree with needing a FDE upper, you could just ceracoat it yourself.

My LPK finally got here today. Had my eye out for upper components, but whole lot of out of out of stock on everything.
One thing I don't like is the bap between the lower and several uppers I put on it at the back where it curves up is larger than the gap on any of my other ARs.
I can live with it, but it will probably annoy me.

They finalized the specs for the full rifle from Brownells. Went with a 16" bbl and an expensive sold out BCG. Also a company came out with a new butstock cap with a storage compartment that KE is supposed to be selling in the future.
 
Yea ke has the buttplates on their site. I already bought M16 trapdoor buttplates though. A couple minutes with a Dremel and they bolt right on. I still need to go over them both with some sand paper on the seems, the (very) little bit of extra flashing or whatever you want to call it annoys me haha.
 
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