Recommendations on a light AR upper

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In my experience it is the weight of the barrel that really makes an AR feel heavy to smaller shooters like women and children who lack upper body strength.

A pinned pencil weight 14.5 barrel and skeletonized handguard is what you seek.


I see some people putting low mass bolt carriers in rifles to shave overall weight without the consideration that changing the mass of the overall operating system may necessitate an adjustable gas block. IMHO that is not the place to shave weight unless you understand what that entails.

So I would say find an upper with a pencil barrel and put a lightweight red dot on it. I like my variable optics but in general they are much more hefty than a quality red dot.
 
Someone correct me if I’m wrong, doesn’t the Sport II already come with a lightweight/pencil barrel? Mine was smaller than the gas block tenon both front and back. I wouldn’t think a true pencil would save more than a few ounces, if any at all.
 
My pencil barrel on my light weight build uses a .625 diameter gas block. I think the Sport II uses a standard front sight tower so its .75 at the gas block.
 
Same applies - we’re not talking about an Hbar vs. a pencil where we can shave a pound off of the barrel, we’re talking a 75 pencil vs a 625 pencil. Ounces of difference at best.

Even comparing a 16” vs. a P&W 14.5”, it’s only a few ounces difference. Unless she is really close to her tolerance threshold, a new barrel profile isn’t going to change too much. Cutting a half pound off of that upper would be a lot to shave.
 
Varminterror said:
Same applies - we’re not talking about an Hbar vs. a pencil where we can shave a pound off of the barrel, we’re talking a 75 pencil vs a 625 pencil. Ounces of difference at best.

Even comparing a 16” vs. a P&W 14.5”, it’s only a few ounces difference. Unless she is really close to her tolerance threshold, a new barrel profile isn’t going to change too much. Cutting a half pound off of that upper would be a lot to shave.
Click to expand...

Assuming I haven't fat fingered my calculator... If we take a cylinder 16 inches long with a .75 in OD and a .625 inch ID we get a volume of ~2.16 in^3. This represent a rough difference in volume between a .75 inch diameter and .625 inch diameter pencile barrel. Steel is ~ .284 lb/in^3 so that would be .613 lbs or about 9.8oz. And ounces equal pounds and pounds equal pain.
 
Good math, bad assumption. The Sport II barrel is ONLY 0.750” at the gas block tenon. The barrel is smaller behind and in front of the tenon. So the difference is only about 2” long, not 16”. If 16” is 9oz, 2” is something just over 1oz.
 
PSA has complete pencil barrel uppers on sale from time to time.

Catch 'em around a holiday...like 4th of July.

M
 
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Varminterror said:
Good math, bad assumption. The Sport II barrel is ONLY 0.750” at the gas block tenon. The barrel is smaller behind and in front of the tenon. So the difference is only about 2” long, not 16”. If 16” is 9oz, 2” is something just over 1oz.
Click to expand...

No I think is more than that. The .625 barrel I am running is only .590 in front and behind the .625 gas block area so I think I am not that far off although I would guess the chamber areas are pretty close to the same but that is not very much of the barrel length. It is very light. I should have weighed the barrel before assembly but the gun completely assembled with BUIS and a 1X red-dot weights in at 6lb 6.5oz (no mag or ammo). And ~4 oz of that is in a chunk of a muzzle break on it for my pending AAC suppressor.
 
Varminterror said:
Someone correct me if I’m wrong, doesn’t the Sport II already come with a lightweight/pencil barrel? Mine was smaller than the gas block tenon both front and back. I wouldn’t think a true pencil would save more than a few ounces, if any at all.
Click to expand...
The Sport II has a carbine gas system with on taper forward of the front sight. Under the handguard it is tapered.
3BE1DE8A-F927-4380-A608-06727F9715C9.jpeg


DeepSouth
A pencil barrel is lighter then a Lightweight . Lightweight barrels are common, but most use a 750 gas block. A true pencil barrel will take a 625 gas block.
Here is the lightweight barrel I used for my youngest son’s Red & Black build. It takes a 750 gas block.
D52C7714-0FF7-4BD1-8650-A37CB58228E5.jpeg
49D97D26-E0A9-492C-84AC-3AFF3E21D906.jpeg

The third barrel down is a lightweight with a 750 gas block area.
The bottom barrel is a pencil barrel with a 625 gas block area.
7D1EA6A3-AFBB-43FA-95F2-6F4A88319071.jpeg

I would take Varminterror up on his offer to build you an upper.
 
@GunnyUSMC - I’m guessing that’s an old photo, so the barrels have found homes by now, but if not, what’s the weight difference in the lightweight vs. pencil you have? I may be surprised, as I’ve never bothered to weigh these two, but have done enough weighing and calculating on length and gas length, I can’t see it being more than 3-4 ounces. Not that a quarter pound is insignificant, but usually when someone comes to me saying their rifle is too heavy, the change to reach their happy place needs to be measured in pounds, not ounces.

I do remember my Sport didn’t have as much GB shoulder as Gunny’s above, the shoulder was only about an 1/8”, like the pencil barrel shoulder... different makers all seem to have their idea of what different common names should be, seems like no two barrels from two makers ever really end up exactly the same.

I also seem to recall losing 3 ounces in cutting the front sight off of the A2 FSB/GB. Ditching the delta ring, retaining ring, and going lightweight free float also drops more than a few ounces....

Usually it takes POUNDS in reduction for shooters to feel like a “too heavy” rifle isn’t too heavy any more... Ounces make pounds, but getting POUNDS lighter than my 16” A2 M4gery, for example, is really simple. Getting POUNDS lighter than a Sport II isn’t as simple. It’s a fun thought experiment to push through how I’d get there without spending a lot of money building a weight weenie AR with EVERY part being hyperlight.

I apologize if I sound like I’m arguing at all, I’m kinda thinking out loud... I’ve built and rebuilt hundreds of AR’s, and USUALLY a lightweight carbine like the Sport II is an easy drop in fit for a “too heavy” problem... it concerns me a little to see the normal “lightweight option” be too heavy still, and then very similarly weighted suggestions come across. It’s a light rifle as is, and probably needs to lose 2lbs to get into her sweet spot - that’s not as easy as it seems.
 
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Varminterror said:
@GunnyUSMC - I’m guessing that’s an old photo, so the barrels have found homes by now, but if not, what’s the weight difference in the lightweight vs. pencil you have? I may be surprised, as I’ve never bothered to weigh these two, but have done enough weighing and calculating on length and gas length, I can’t see it being more than 3-4 ounces. Not that a quarter pound is insignificant, but usually when someone comes to me saying their rifle is too heavy, the change to reach their happy place needs to be measured in pounds, not ounces.

I do remember my Sport didn’t have as much GB shoulder as Gunny’s above, the shoulder was only about an 1/8”, like the pencil barrel shoulder... different makers all seem to have their idea of what different common names should be, seems like no two barrels from two makers ever really end up exactly the same.

I also seem to recall losing 3 ounces in cutting the front sight off of the A2 FSB/GB. Ditching the delta ring, retaining ring, and going lightweight free float also drops more than a few ounces....

Usually it takes POUNDS in reduction for shooters to feel like a “too heavy” rifle isn’t too heavy any more... Ounces make pounds, but getting POUNDS lighter than my 16” A2 M4gery, for example, is really simple. Getting POUNDS lighter than a Sport II isn’t as simple. It’s a fun thought experiment to push through how I’d get there without spending a lot of money building a weight weenie AR with EVERY part being hyperlight.

I apologize if I sound like I’m arguing at all, I’m kinda thinking out loud... I’ve built and rebuilt hundreds of AR’s, and USUALLY a lightweight carbine like the Sport II is an easy drop in fit for a “too heavy” problem... it concerns me a little to see the normal “lightweight option” be too heavy still, and then very similarly weighted suggestions come across. It’s a light rifle as is, and probably needs to lose 2lbs to get into her sweet spot - that’s not as easy as it seems.
Click to expand...
Don’t worry, I have been known to think out loud and fart in public from time to time. ;)
I understand that getting an AR lighter without going with super lightweight material is hard and sometimes all you are doing is shaving ounces. But the old saying in the military is “An ounce is a pound at the end of the day”.
I still have those five barrels, and have added a few more. I just keep finding great sales. :)
I’m not sure the weight difference between the lightweight and the pencil barrel is but it is noticeable.
My youngest son, Isaac, has two AR’s . Here’s a pic of them.
There’s about a half pound difference in the two with the red one being the lighter. It has a lightweight barrel and lightweight rail. Isaac says that the red one is much lighter, but I know that it’s really that much of a difference. But I will say this, the red one has a better balance.
30614D32-4DC8-4F01-ACAE-CEA322295D99.jpeg
 
A couple of comments about my build.

First I consider it to be a "light(er)" instead of a "light" weight build.

Second is I have trouble focusing the Magpul MBUS front sight. However I don't have any problems with the M-16/M-4 style tower front sight. I don't know why, maybe because the steel sight post corners are a bit sharper.

Three I choose the fixed front sight tower since I can see the steel front sight post better.

Fourth in choosing the tower front sight base this meant I had to use a .750" diameter for the FSB gas block.

Fifth in doing so it was a matter of reducing the weight of the M-4 barrel which I did with the Del-Ton.

Sixth is I choose the Magpul Carbine handguard due to it's light weight. (I also did not want to remove the FSB to install a free float tube. I am probably going to do that with the Purple People Eater build (#4).)

I am also reducing the overall weight of the gun by using Mission First Tactical buttstock (6.0 oz.) and grip (2.2. oz.).
I spent a lot of time reviewing part weights of polymer and titanium parts and in the end decided it was not worth the extra cost. I am cool on using polymer upper receiver and Titanium parts are much more expensive than steel.

Depending on how well I like the gun and the feedback from the ladies a pencil barrel with lightweight free float handguard may be in the future.
 
You can get a FSB gas block in both .750 and .625 if you like. The original M16 and M16A1 used .625 gas blocks.
 
BSA1 said:
A couple of comments about my build.

First I consider it to be a "light(er)" instead of a "light" weight build.

Second is I have trouble focusing the Magpul MBUS front sight. However I don't have any problems with the M-16/M-4 style tower front sight. I don't know why, maybe because the steel sight post corners are a bit sharper.

Three I choose the fixed front sight tower since I can see the steel front sight post better.

Fourth in choosing the tower front sight base this meant I had to use a .750" diameter for the FSB gas block.

Fifth in doing so it was a matter of reducing the weight of the M-4 barrel which I did with the Del-Ton.

Sixth is I choose the Magpul Carbine handguard due to it's light weight. (I also did not want to remove the FSB to install a free float tube. I am probably going to do that with the Purple People Eater build (#4).)

I am also reducing the overall weight of the gun by using Mission First Tactical buttstock (6.0 oz.) and grip (2.2. oz.).
I spent a lot of time reviewing part weights of polymer and titanium parts and in the end decided it was not worth the extra cost. I am cool on using polymer upper receiver and Titanium parts are much more expensive than steel.

Depending on how well I like the gun and the feedback from the ladies a pencil barrel with lightweight free float handguard may be in the future.
Click to expand...
Your pretty much building one like this. The difference is I used a Bootleg lightweight upper and Tennessee Arms lower..
A7AC0E3D-6E0A-407B-9325-762BF6E834EC.jpeg
 
Ian and Karl over at InRange for their What Would Stoner Do project used the Faxon pencil barrel in their project. That went on an Aero Precision upper with Faxon enhanced carbon fiber fore end. With the GWACS polymer lower, their all-in assembled weight weight was 5.5 pounds (with a HoloSun sight aboard). Which is what an M-1 Carbine weighs, for comparison.

Link to parts list: https://www.reddit.com/r/ForgottenWeapons/comments/6zz05u/wwsd_rifles_components_list/

Food for thought. To go with my 2¢
 
BSA1 said:
Yep except I am using the Magpul MOE Carbine handguard and everything is black.
Click to expand...
Have you looked at the slim handguard. It gives you about two more inches of handguard and covers the front sight base. If you have ever touched the front sight base while shooting, you know why they designed the slim handguard that way. You do have to remove the front sling swivel and have a round handguard cap to use the slim handguard.
The barrel on my build I’d a Delton lightweight mid length.
I’ve built three with this barrel and they have all been great shooters. I got two of them from JSE Surplus. They were $150 and came with the front sight parts. They came with the triangle handgun cap, which I had to change.
http://www.jsesurplus.com/Del-Ton16Midlength1x9MolyBarrelStripped-1-2.aspx
The last one I ordered from Delton. The barrel was $154 plus an extra $5 for the front sight parts. But I requested a round handguard cap to be installed and they said no problem. Well the barrel showed up with a triangle handguard cap installed and a round handguard cap in the box . When I called the lady told me that she was sorry and if I shipped it back they would install the round cap. I told her that I would just do it myself because I had ordered it with the round cap to save time and I didn’t feel like paying the shipping so that they could fix their mistake. But I love the barrel.
 
GunnyUSMC,

Being a newbie I did not know about the different handguard end caps so mine came the triangle one. As the standard Magpul MOE will work with both styles that is why I have it on my list. (Next time I will know better).

I do like the slim handguard better so I may consider installing the round end cap. I almost ordered the handguard this weekend but found a sale on the Mission First Tactical buttstock and grip so I have them ordered instead.

To the O.P.,

I have pretty much hijacked your original question. I wanted to show you the options available and how much cheaper it is if you "build" it yourself. (Like I said the only part that requires a special tool is the barrel nut). Up until 2 years ago I had never even touched a AR-15 and now I have two complete AR's, current build for which I have 90% of the parts for and am accumulating the parts for build #4. These dang things are addictive! (Of course as responsible, caring Dad it is my duty to ensure my kids each have their own AR right?) :D:D:D
 
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BSA1 said:
GunnyUSMC,

Being a newbie I did not know about the different handguard end caps so mine came the triangle one. As the standard Magpul MOE will work with both styles that is why I have it on my list. (Next time I will know better).

I do like the slim handguard better so I may consider installing the round end cap. I almost ordered the handguard this weekend but found a sale on the Mission First Tactical buttstock and grip so I have them ordered instead.

To the O.P.,

I have pretty much hijacked your original question. I wanted to show you the options available and how much cheaper it is if you "build" it yourself. (Like I said the only part that requires a special tool is the barrel nut). Up until 2 years ago I had even touched a AR-15 and now I have two complete AR's, current build for which I have 90% of the parts for and am accumulating the parts for build #4. These dang things are addictive! (Of course as responsible, caring Dad it is my duty to ensure my kids each have their own AR right?) :D:D:D
Click to expand...
The Slimline handguard is well worth swapping the end caps for.
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View attachment 794877

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