Budget AR build, any tips or suggestions?

[Diamondback]

I know the feelin', amigo--I'm in the same boat.

 

[Newbuilder223]

Newbie question coming up, what's the difference in function between a carbine length gas system and mid length on a 16in barrel.

 

[Newbuilder223]

Also can anyone tell me about andersons am-15, found what could potentially be my budget rifle if it's regarded well enough, rifle I'm looking at is upper and lower without furniture. It'll need a stock, grip, handguard, and sights, everything else is there, supposedly has a match grade fcg.

 

[Raidingtime]

Newbie question coming up, what's the difference in function between a carbine length gas system and mid length on a 16in barrel.

To better answer your question I'll go into the function of the firearm. The bullet is propelled down the barrel from the end of the BCG by gas pressure once the firing pin hits the primer of the casing. Some of this gas pressure is channeled off at an hole, along the length of the barrel, a distance down the barrel. This gas that is directed away from the end of the barrel into this channel goes through a gas block, into a gas tube that runs parallel to the barrel, through the upper, and ends it's useful life by hitting the gas key on the BCG. This action causes the rifle to cycle. So....

The length of the gas system correlates to how far away the gas hole coming off of the barrel is from the BCG's gas key. Their are 4 sizes of gas systems that I'm aware of: pistol, carbine, mid length, and rifle length gas systems. The pistol's gas hole is closest to the upper while the rifle is the furthest away. As far as I know they all work just fine. I've read online that the mid length and rifle length systems are supposedly softer shooting than the carbine length gas system. I have not verified this. As far as I know it's just a cosmetic difference that has to do with how far down your tube the gas block will be located. None the less, M4s use carbine length gas systems.

I have no input on the Anderson rifle because I've never used one and don't have any friends with one. However, Anderson has a good reputation and it's mostly likely a good kit.

Also, if anyone ever tells you that you need a piston kit just walk the other way or ignore them because they're probably drunk.

 

[3MTA3]

Newbie question coming up, what's the difference in function between a carbine length gas system and mid length on a 16in barrel.

To better answer your question I'll go into the function of the firearm. The bullet is propelled down the barrel from the end of the BCG by gas pressure once the firing pin hits the primer of the casing. Some of this gas pressure is channeled off at an hole, along the length of the barrel, a distance down the barrel. This gas that is directed away from the end of the barrel into this channel goes through a gas block, into a gas tube that runs parallel to the barrel, through the upper, and ends it's useful life by hitting the gas key on the BCG. This action causes the rifle to cycle. So....

The length of the gas system correlates to how far away the gas hole coming off of the barrel is from the BCG's gas key. Their are 4 sizes of gas systems that I'm aware of: pistol, carbine, mid length, and rifle length gas systems. The pistol's gas hole is closest to the upper while the rifle is the furthest away. As far as I know they all work just fine. I've read online that the mid length and rifle length systems are supposedly softer shooting than the carbine length gas system. I have not verified this. As far as I know it's just a cosmetic difference that has to do with how far down your tube the gas block will be located. None the less, M4s use carbine length gas systems.

I have no input on the Anderson rifle because I've never used one and don't have any friends with one. However, Anderson has a good reputation and it's mostly likely a good kit.

Also, it's my suggestion not to drink the "piston kit AR" kool aid. Direct impingement works just fine and is extremely reliable. People that buy piston kits for their ARs are people that like to brag instead of shoot. Yep I just threw that down

Building on the gas system discussion,when you hear the term "dwell time" it's the length of time that the pressurized gas is present at the hole - this the the time from when the bullet just clears the hole until the time it exits the barrel. The longer the dwell time the more gas goes through the gas block and back into the bolt.

The carbine length gas system was developed for the 14.5" barrel used by the military, so when used in a 16" barrel is a bit over gassed. It still works just fine and reliably for both barrel lengths, but a mid length gas system gives you the same amount of gas in a 16" barrel that a carbine system does in a 14.5" barrel. The result is that the felt recoil is a bit softer and comparable to a carbine 14.5" system.

Regarding Anderson, the non-lubricated version was considered a bust by the machine gun rental people in Las Vegas who as you might gather put 1,000's of rounds through their rifles every day. I'd consider the standard Anderson rifle properly lubricated as just fine. I don't know if they follow all the guidelines like staking the castle nut, etc., but they have a decent reputation. Just know you are not getting Colt LE6920 quality.

Piston vs DI is a non issue. Both systems work well and are reliable. DI is less expensive but requires more frequent cleaning and lubrication. Nothing is perfect and everything is a compromise.

Edit: Battlefield Las Vegas report here: AR endurance findings, at a rental range - The Firearm Blog

BTW, they are not fond of piston systems there.

 

[Newbuilder223]

Guess I'll have to make the ultimate decision come crunch time Friday. The blem PSA CHF upper is still available I'm hoping it still is come Friday, from what I've been reading and has been corroborated here I was ideally looking for mid length, but everything available is all carbine so I might end up settling. It's between that and building up the lower, or getting the Anderson and furniture. I'm thinking Anderson will be the more budget friendly option but PSA may be more long term satisfaction.

 

[lucifermonkey]

Carbine, Mid, Rifle length is really a matter of choice. Get whatever you like the looks of. Here is an image showing the cosmetic differences:

http://cdn.shopify.com/s/files/1/0231/2927/files/gas_system_lengths_large.jpg?7297056845043836051

Also, there are far more options for "toys" on the mid length system (which seems to be the most popular).

Newbie question coming up, what's the difference in function between a carbine length gas system and mid length on a 16in barrel.

 

[Newbuilder223]

Battlefield Las Vegas report here: AR endurance findings, at a rental range - The Firearm Blog

I found this very informative (and damnit do I wish I could work there.) I think based on this I'm going to go with the PSA CHF, if I have to wait then so be it.

 

[CamoDeafie]

Heard somewhere that the mid length makes it far easier to mount usgi bayonets on 16" barrels because of the length from front sight base to muzzle device compared to the carbine length gas port location on 16" barrels....

 

[Diamondback]

Heard somewhere that the mid length makes it far easier to mount usgi bayonets on 16" barrels because of the length from front sight base to muzzle device compared to the carbine length gas port location on 16" barrels....

It also allows longer sight radius, and less recoil from the lower pressure gas not ramming the BCG back as hard IIRC.

 

[partsed]

Also can anyone tell me about andersons am-15, found what could potentially be my budget rifle if it's regarded well enough, rifle I'm looking at is upper and lower without furniture. It'll need a stock, grip, handguard, and sights, everything else is there, supposedly has a match grade fcg.

I bought an Anderson AR15 last year from Sportsmans Guide and it had everything on it. Of course, I had to customize with Magpul furniture and really enjoy shooting it.

 

[Brutus57]

It also allows longer sight radius, and less recoil from the lower pressure gas not ramming the BCG back as hard IIRC.

One of the reasons I went with a BCM HBAR middie upper.

Brutus Out

 

[Diamondback]

One of the reasons I went with a BCM HBAR middie upper.

Brutus Out

Of course, if you really want longest possible sight radius that means lo-pro gas block and the longest top-rail that can fit with your barrel... kind of like what I'm thinking to build where the HG is about an inch past end of barrel with a linear comp about an inch past that. LOL

 

[3MTA3]

I'll take a shorter sight radius with the sight attached to the barrel or gas block any day. Rails move and flex enough to throw off the front sight. Check for yourself by applying pressure to the front of the rail, and the longer the rail the more leverage and the easier it is to move it.

 

[Raidingtime]

It's funny how my personal desire of an AR have evolved. I was given one in the Navy that had the DD rail system on it, full auto, a flash light, red dot, and vertical grip. Funny that I had never shot any sort of rifle similar to that one before I was given one- heck no one even gave me an explanation of how to even operate it before live fire began... Kind of a stressful ordeal when you've got a former special forces dude as your instructor screaming at you to lock the bolt back hahaha.

Got out and decided to get the civilian equivalent. Read about how much "better" free float rails were and decided to go that way. They look cool right!? Since then I've shot both with a variety of accessories. Now all I want is a 20" chrome lined SP1 or A2 clone....

 

[3MTA3]

It's funny how my personal desire of an AR have evolved. I was given one in the Navy that had the DD rail system on it, full auto, a flash light, red dot, and vertical grip. Funny that I had never shot any sort of rifle similar to that one before I was given one- heck no one even gave me an explanation of how to even operate it before live fire began... Kind of a stressful ordeal when you've got a former special forces dude as your instructor screaming at you to lock the bolt back hahaha.

Got out and decided to get the civilian equivalent. Read about how much "better" free float rails were and decided to go that way. They look cool right!? Since then I've shot both with a variety of accessories. Now all I want is a 20" chrome lined SP1 or A2 clone....

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You mean Stoner got it right the first time around? So damn true, even down to the thinner barrel profile. I do prefer the carbine length of the M4, but that A2 is as good today as it was then. The trick seems to be not letting fashion make our decisions for us. "Honey, does this free float rail make my butt look fat?"

 

[3MTA3]

Good video to watch when you are picking out your buffer:

 

[Raidingtime]

You mean Stoner got it right the first time around? So damn true, even down to the thinner barrel profile. I do prefer the carbine length of the M4, but that A2 is as good today as it was then. The trick seems to be not letting fashion make our decisions for us. "Honey, does this free float rail make my butt look fat?"

Definitely. haha I like your last comment. I feel like between the two of us were dogging other AR builders a lot .

It is good to try new things for R and D. Some things have been improved over the years i.e. chrome lining, full auto serrations, dust cover, forward assist, Geissele triggers, magpul stuff, etc. I also like the badger ordinance extended charging latch but some may not especially it they're concerned about getting the extended latch caught on clothing or molle. It is true that some things that have been thought up for the AR are purely consumer items or ideas that look good on paper but aren't as practical as initially thought. For example, look at how many people still prefer an AK. I mean they don't even have a LRBHO! Barbarians!

 

[3MTA3]

Definitely. haha I like your last comment. I feel like between the two of us were dogging other AR builders a lot .

It is good to try new things for R and D. Some things have been improved over the years i.e. chrome lining, full auto serrations, dust cover, forward assist, Geissele triggers, magpul stuff, etc. I also like the badger ordinance extended charging latch but some may not especially it they're concerned about getting the extended latch caught on clothing or molle. It is true that some things that have been thought up for the AR are purely consumer items or ideas that look good on paper but aren't as practical as initially thought. For example, look at how many people still prefer an AK. I mean they don't even have a LRBHO! Barbarians!

It probably sounds that way, but my AR journey has come a long ways since I started. If I were building a 600 yard SPR style AR-15 or a longer range AR-10/308 I'd go free float tube all day long. Same if I were building a rifle I intended to use a lock arm firing position. I'm also using a heavier barrel profile for greater long range repeatability shooting multiple rounds.

My practical AR philosophy is that if I'm using the rifle for defense I'm either as low as I can get or I'm hiding behind a barrier. I want light, ergonomic, and fast. For me that translates to a mid (preferred) or carbine length non free floated configuration with a lighter but not pencil barrel (Hanson, GUNNER, BCM ELW, etc). Love my MagPul, Geissele/ALG, Minimalist to finish it all off, but that's just what I prefer. Lock arm to me only works when I'm able to stand up and be exposed which is definitely NOT my preference. It's great for three gun, but sux when you are getting shot back at.

Rock on and build your AR the way you want and the great thing is the modularity, so you can always tear down and rebuild selling what doesn't work. I'm not here to be a wet blanket on anybody's dream AR.

 

[Raidingtime]

I found this very informative (and damnit do I wish I could work there.) I think based on this I'm going to go with the PSA CHF, if I have to wait then so be it.

<broken link removed>

Get this kit and an aeroprecision or anderson lower from Curt's and you're set buddy. Primary Arms has a good deal on anderson's as well if Curts is too far a drive for you. IDK what shipping costs are but for 550 + shipping and transfer fees (I'm guessing $80-100 total= $630-650ish) you can have a rifle that is basically the same quality as Colt 6920. BTW I've bought a blemished lower from PSA before (it's on the stormtrooper) and couldn't find the imperfection.

Only thing missing is the extra nice anodizing and the horsy.