Rifle length AR-15

[The Father]

Have Carbine and Mid-length AR-15's. Planning on getting a rifle length AR-15.

18" or 20" barrel? The 20" picks up about 100 fps if am correct. What do you rifle aficionados' think, 18" or 20"? One better than the other or just preference. Both would have a 15" free floating handguard.

[MikedaddyH]

It depends on what you want it to do ?

Do you golf with just one club ? No ! So why not have a bunch of different size gun barrels.

[The Father]

To reach out farther, with the 15" handguard you get really good eye relief with iron sights. So say 300-400 yards is the 18" gonna be any different than a 20"? 

I do have several excess 16" AR's. But with today's fire sales on AR's the excess isn't worth much. 20" was the old standard for rifle length, probably go that way. Guess I can get a 3rd gun safe.

Edited April 27, 2017 by The Father

[Sisco]

23 hours ago, The Father said:

To reach out farther, with the 15" handguard you get really good eye relief with iron sights. So say 300-400 yards is the 18" gonna be any different than a 20"? 

I do have several excess 16" AR's. But with today's fire sales on AR's the excess isn't worth much. 20" was the old standard for rifle length, probably go that way. Guess I can get a 3rd gun safe.

If you are looking for distance accuracy I would go with the 20" 1 in 7 twist. Pair up with 75-77 grain BTHP's that will get you the most distance before you get key holing. Should make 500 yards pretty easy,  unless of course, you want to go 22"- Law of diminishing return after that. Find some info on the Marine Marksmanship team, they did some innovative work with the 5,56.

[sketch]

223 wylde.... 

[survivalshop]

11 hours ago, Sisco said:

If you are looking for distance accuracy I would go with the 20" 1 in 7 twist. Pair up with 75-77 grain BTHP's that will get you the most distance before you get key holing. Should make 500 yards pretty easy,  unless of course, you want to go 22"- Law of diminishing return after that. Find some info on the Marine Marksmanship team, they did some innovative work with the 5,56.

 I have a 24" 1-10 twist HB ,that does just fine .  Olympic Arms Ultra Match Barrel & Receiver's/parts with military contract M16 BCG . I Built it in 1978 or 79 , don't remember exactly .

  Now would I purchase another one that length , probably not . 20" is just fine , the  AR rifle was originally designed around that length.

[bubbas4570]

I don't know, I am very happy with my rifle length 16".....

Dissipators RULE!

[98Z5V]

On 4/27/2017 at 4:37 PM, Sisco said:

If you are looking for distance accuracy I would go with the 20" 1 in 7 twist. Pair up with 75-77 grain BTHP's that will get you the most distance before you get key holing. Should make 500 yards pretty easy,

That combo makes 800 yards pretty easy, honestly. 

I've been stuck with the Hornady 75gr BTHP projectiles for several years now.  Very, very slight accuracy edge with those, over the Sierra 77gr BTHP Matchkings.  Seriously.  Cram 24.0gr of RL-15 under a Hornady 75gr in Lake City brass, and you're cooking 2750 fps.  You can go higher on the powder charge, but you better test them yourself, incrementally, in very small increments, too.  If your brass and chamber live through it, you can pull 2850fps with that combination of components. 2750fps is a great speed for those bullets. 

EDIT - ^^^  In that info above, I am NOT talking about the Hornady 75gr AMAX projectile.  I' talking about the 75gr BTHP, Hornady item # 2279...  You can't load that AMAX to mag length...   Don't blow your shiit up... 

Edited May 4, 2017 by 98Z5V

[edgecrusher]

5 hours ago, 98Z5V said:

That combo makes 800 yards pretty easy, honestly. 

I've been stuck with the Hornady 75gr BTHP projectiles for several years now.  Very, very slight accuracy edge with those, over the Sierra 77gr BTHP Matchkings.  Seriously.  Cram 24.0gr of RL-15 under a Hornady 75gr in Lake City brass, and you're cooking 2750 fps.  You can go higher on the powder charge, but you better test them yourself, incrementally, in very small increments, too.  If your brass and chamber live through it, you can pull 2850fps with that combination of components. 2750fps is a great speed for those bullets. 

EDIT - ^^^  In that info above, I am NOT talking about the Hornady 75gr AMAX projectile.  I' talking about the 75gr BTHP, Hornady item # 2279...  You can't load that AMAX to mag length...   Don't blow your shiit up... 

Hell we bet on 450 yds with a 14.5" with a red dot during our challenges.....

[The Father]

Went with a 20" rifle length AR. I know you were all waiting on the edge of your seats for the decision.

[98Z5V]

I have 2 of them, man. Both are great, and love them.  One is a YHM 20" 1:7 heavy cromo barrel, 5.56 NATO chamber, scoped, and that things shoot the lights out, at distance. 

The other is The Woody...  Built this gun as a National Match iron sight rifle...  RRA 20" 1:8 heavy stainless barrel, .223 Wylde chamber, National Match iron sights, and it shoots the lights out, too - for iron sights.  Taken it out to 450 without issue.  Need to stretch it out more, but just haven't done it.  That will be coming this fall, though... 

[The Father]

National match iron sights, where can I get those?

[mrmackc]

Not being one to feel superior or boastful but my choice for a set of NM iron sights was to order out a new Super match Springfield M1A rifle attached to a set of Real NM iron sights for a bit under $2700.

[COBrien]

1 hour ago, mrmackc said:

Not being one to feel superior or boastful but my choice for a set of NM iron sights was to order out a new Super match Springfield M1A rifle attached to a set of Real NM iron sights for a bit under $2700.

So... you bought the sights for $2700 and they threw the rifle in for free? What a deal!

I'd check out Fulton Armory. I ordered a NM front sight post from them for my Dissipator build and, IIRC, they carry NM rear sights as well (in carry handles). Be prepared to spend some money, though -- these ain't no MagPul BUIS...

[98Z5V]

8 hours ago, The Father said:

National match iron sights, where can I get those?

I did the NM A2 carry handle rear sight from RRA, 1/4 x 1/4 MOA with 0.040 aperature, and not the 1/2 x 1/2 MOA version.  It's on this page:

:https://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=280&CFID=604213399&CFTOKEN=91782427

For the front, I used the Armalite clamp-on A2 sight base with a KNS precision .040" square front sight post.

 

Finally found the thread on that build. 

 

Edited May 6, 2017 by 98Z5V

[jtallen83]

I think you could upgrade a regular iron sight set with these parts from Armalite, they are clearing them out, save you from buying RRA after there foray into politics;

https://armalite.com/?s=national+match

 

6 hours ago, 98Z5V said:

I did the NM A2 carry handle rear sight from RRA, 1/4 x 1/4 MOA with 0.040 aperature, and not the 1/2 x 1/2 MOA version.  It's on this page:

:https://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=280&CFID=604213399&CFTOKEN=91782427

For the front, I used the Armalite clamp-on A2 sight base with a KNS precision .040" square front sight post.

 

 

 

[98Z5V]

There's a couple places that have them - FA sells the Northern Competition NM setup, which it the top of the line. 

http://www.fulton-armory.com/carryhandledetachablewnortherncompetition14x14hoodednmsights.aspx

Compass Lake Engineering used to sell them, but I don't see them listed on their website right now.

[unforgiven]

White Oak Armament got the entire upper w/ 1/4 X 1/4 .042 pinned rear aperture : https://www.whiteoakarmament.com/shop/highpower-competition/rear-sights-components/1-4-min-nm-carry-handle-pinned-includes-038-042-046-hoods.html