So I would LOVE to hear from any of you with experience building super lightweight AR15 rifles or carbines.  

What kind of consistency of accuracy are you able to get, with cold 5 shot groups, and then with barrel hot, another 5 or 10 shot group??

I have built a 5.56 using a Faxon 16" SS pencil barrel with mid-length gas, SLR Sentry adjustable block, aluminum bolt carrier, and with Leupold 3-9 scope mounted, it weighs 5.2 pounds.
Super easy to carry afield and get in/out of truck.  

I am still in the process of figuring out which ammo it likes best, but have shot a few 1 inch and slightly less 3 and 5 shot groups at 100 yards from lead sled.  However, also had a hard time on other days shooting 3 inches at 100 yards.  Most likely problem is the shooter- oh maybe the ammo- but likely the shooter

Anyone with Faxon builds, or other similar lightweight rigs, have any reports, stories, warnings, etc ?

Thanks yall and happy shooting from this brand new member here!

I didn't shoot too many groups since I was using a red dot, but I have a Faxon Pencil barrel as well and it shot 1 inch groups. 6 lb loaded with red dot. I was using 75 gr Gold Dot Softpoints and a Geissele 2Stage Trigger. Remember that a barrel/gun can shoot sub moa, but that's at it's BEST. Generally you will see around 1moa unless you use handloads and whatnot. But I wouldn't be surprised if my gun shot 2moa on a random day. They weren't cold bore shots when I shot 1 moa but I did wait a minute or two before each shot and about 5 mins between groups.

Hope this helps. I have a faxon 16" pencil its more accurate than i am. I dont do bench rest shooting.
https://www.youtube.com/watch?v=jnDsNTi4nmM&t=187s

Cool. Yes, that's helpful and a good video.  

I dont handload-yet- but do shoot only higher quality factory ammo like Hornady and Black Hills.  Occasionally I've shot cheaper stuff, and it seems I still get good 1MOA or so groups, minus one or two shots.  Um, well, maybe then that's not exactly 1MOA.... we do get to just count the best few shots each time right

Main reason for this thread was my concerns from hearing some guys claim a very lightweight barrel and rifle is not a good choice for consistent mid to long range shooting.  I decided to go with my gut instinct, and based on my experience with other rifles, and my real world level of accuracy needed..... ultimately I decided a carbine with good quality components, built properly,  with good optics, ammo, and shooter- would work for me.

I hunt varmints in Indiana on our farm and hunt predators. Most shots 200 yards or less on medium or small critters.  For this, a few hundred foot lbs energy with fragmenting or expanding ammo is easily enough for humane clean kills every time.  IF the shot is right on target.  So from bipod or shooting sticks, if rifle shoots 1MOA out to 300 to 400 yards for a couple few shots at a time, I have met my goals just right- and it seems a 16"carbine in 5.56 is perfectly sufficient for this.  Not to mention fun to shoot, and super easy to have behind the truck seat or pack around on a sling and barely know its there.

Awesome platform of weapon and amazing amount of options available these days.  Fun and easy to build as well. All is good

'Consistency of accuracy' I believe you mean precision :)

I think for hunting pencil is perfectly fine. If you plan on shooting varmint at a high rate of fire it still should be fine. If it's a high rate of fire at a longer range like 300-400+ yards than I might go for a thicker profile.

14.5" pencil barrel here.  Shoots great and is pleasingly accurate, but I only have access to 300 yard lanes.

I just finished up this build using Faxon's 16in pencil. hopefully i can get out and test it here in the next couple of weeks. ill update on the accuracy when i can..

Yeah, that's what I was tryna say

That is exactly what I'm thinking too.  I know that for my hunting and varmint shooting around our farm and woods, it's rare to need to shoot more than 6 or 8 shots at a time- usually more like two or three.  Then everything runs, flies, or goes down their burrows or holes  for a few minutes or more.... and said thin barrel quickly cools back down.

The quality of the barrel material, rifling, and crown probably makes ALL the difference for this type of shooting.  I know that the light weight is REALLY nice and REALLY noticeable when carrying this rifle around, so it only makes sense -to me- to at least try these pencil profile barrels first..... still fine tuning and practicing but looks like it should easily be accurate enough for my needs.

Thought I'd share a few pics of this lightweight varmint hunting rifle build of mine.

First complete build for me. Super fun and satisfying.  I completed an 80% lower for it and put in a RRA 2-stage varmint trigger.  

Used a 10" free float 2A Armaments MLok rail on mid length -- I personally like this look better than longer handguards/rails.

A 16" faxon pencil I have will do 1moa with my handloads. The barrel is free floated, has 9x glass and G2S trigger.. that's all I expected and am very happy with that.

That's 5 shot groups.

Awesome!! Good to hear, I'm hoping mine does stay at that mark with good factory ammo till I can get started handloading.  

Side note/ question- are pics of animals shot with rifles ok to post here, or frowned upon?

This being a gun but not specifically hunting forum I wasn't sure..... some blood in a couple I was considering posting here

Shit

Woops.  Um, those aren't showing up as pictures for y'all are they??

..


Good thread.  But no pics.





..

I agree. Although certainly not great quality pics (phone) or the coolest/baddest rifle build ever.... here are a few random ones I snapped from the build process and the newly finished rifle complete.

Also a couple photos of my first AR, which was just bought as a separate upper and lower each already completed. Then I just slapped on the OD green Magpul furniture.

Technical difficulties

More technical issues , yep it's on my end

Got an imgur page/ link set up now. Fancy.
http://m.imgur.com/a/VeKDZ

Pics are at least now linked too. Nice set up.

PS: now you don't have to link pictures, you can upload them straight from your computer if you would like.
1. They have to be smaller than 3mb.
2. I don't think you can load them from a smart phone or tablet.
3. Select File (Browse for pic on computer)
4. Upload.
5. Submit.

Attached File

You can upload from a phone, I do it all the time.

I think you have to be a paid member but I'm not sure.

Thanks for pointing that out. That must be the case, I don't have the spell check on mine, or 'media' or any of that.