PDA

View Full Version : Pairing down, if you can only keep 3 ARs.



Erni
06-25-2014, 08:09
Hi folks,
I have decided that I just need to pair down the stable of ARs, get rid of a few, keep only three. I never shoot most of them, but thought I would pair it down and just concentrate on the following:
1. Light 16" gun: standard m4 type barrel minus the launcher cut, with light free float handguard, BUIS, MOE furniture, needs a light RDS to be complete
2. Medium 16" gun: RRA heavier profile barell (not bull/varmint), needs a lighter free float handguard, some furniture updates, and has a 1-4 Millet. (not seksy but very accurate)
3. Heavy 24" gun: 24" SS barrel, round free float handguard, A2 stock, flat top reciever, currently sporting russian glass with a german post reticle (scope sucks for parallax needs updating)

What wold be the three you keep? Any sugestions on the 3 gun setup I created?

MarkCO
06-25-2014, 08:57
Lightweight 16" AR, 5.56 chamber, NiB coated BCG, simple flash hider, simple RDS or laser and BUIS, maybe 6 pounds or so.

Medium 18", .223 Wylde Chamber, 1-4 or 1-5 optic in one piece mount, carbon fiber HG, low mass BCG, comp.

Heavy 20", .223 Wylde Chamber, 3 or 4 x on bottom to 12 to 20x on top, threaded for suppressor, Seekins flat bottom HG, standard carrier with enhanced bolt.

Great-Kazoo
06-25-2014, 09:12
The 3 you shoot best.

Erni
06-25-2014, 10:02
@MarkCO, curious why 20" vs longer on the heavy?

Yarg!

MarkCO
06-25-2014, 10:25
@MarkCO, curious why 20" vs longer on the heavy?

Yarg!

The longer the barrel, the thicker it needs to be to maintain accuracy. On a gas gun, ALL of the barrel mass is hung on aluminum threads with varying degrees of tolerance. Even with a shimmed, or thermal fit barrel torqued above 75 ft-lbs, you will get some thermal drift. The 20" barrels minimize that effect due to less leverage on the threads. The increased accuracy is more important to me than 100 fps of velocity.

I built identical Kreigers, and the 20" had less drift of the POI as compared to the 24". Both shot very small groups, the 24" just walked them around a little bit more based on ambient temperature and the barrel temperature.

Not saying a 24 is bad at all and depending on what you shoot and how, the 24 might offer some benefits over the 20. For me, the 24 does not provide me any benefit over the 20.

68Charger
06-25-2014, 10:31
I'd say because off-the-shelf ammo won't gain velocity with more than 20" of barrel...
You generally have to reload with slow-burning powder to take advantage of a 24" barrel in .223/5.56
Since you said ARs, make the Heavy an AR10/LR308... .308 can take advantage of a 24" barrel, and is better suited to >400yrd

if sticking with AR15s, why not take advantage of the modularity of the platform and go with 2 lowers (one light, one precision), and maybe 4 uppers (at least one in an alternative caliber)

Erni
06-25-2014, 11:23
Curious as how you arrived at thermal drift vs whippiness of barrel.
An AR10 will be a future decision, plus I like my FAL. ( I realize the fal is less accurate and has faults but its a FAL!) [emoji7]

Yarg!

MarkCO
06-25-2014, 11:57
Curious as how you arrived at thermal drift vs whippiness of barrel.

Lots of testing is the bulk of it. When the barrel heats up and the group sizes are the same, but the center moves, that is one indicator. Temperature measurements combined with the metallurgical properties and vibration analysis is another indicator. Inductive heating of the chamber alone, and seeing progressive change in POI due to the heat transfer is another indicator.

Chad0724
06-25-2014, 12:50
I only have 1 :(

vectorsc
06-25-2014, 12:55
I wouldn't go with 3 - Id do exactly what I do now.

Best SBR lower you can build +
20" Match Upper
9" 300 Blackout Upper

Swap accessories depending on what is needed at the time. That way you get every benefit of being short and every benefit of being long. And you can afford the better toys like surefires and aimpoints and such because it's only 1 gun.

Erni
06-25-2014, 15:56
... Inductive heating of the chamber alone, ....

Inductive or induced?

Yarg!

MarkCO
06-25-2014, 16:01
Inductive

Goodburbon
06-25-2014, 16:01
Look closer at the "medium" and see what it gives you that the others don't. Seems like it is just a compromise in every way. And your "1" gun for any situation. While only the heavy has a specific purpose.

If you must have only 3, have some actual variety. Like other calibers.

1 heavy varmint with 10x+ magnification and bipod
1 lightweight, (you can use QD mounts to switch optics as the application dictates) aimpoint, 3x.
1 heavier caliber. 300blk, 6.8, 6.5 etc, with the rifle built to the purpose for that round.



Or keep dust collectors. Heck I can't narrow it down.


Sent from my iPad using Tapatalk HD

Erni
06-25-2014, 16:01
...
You generally have to reload with slow-burning powder to take advantage of a 24" barrel in .223/5.56
...

Can you point me at some 24" load recipes? If the 24" vs 20" velocity is negligible then a trip to a smith might be in order....

Yarg!

crays
06-25-2014, 17:09
Sent via Mobile Work Avoidance Device

ETA: Empty post, oops. Hit submit, instead of discard.

nisils14
06-25-2014, 17:41
If I had to keep it to 3 these would be mine.
- Chrome lined govt. profile middy 16" for general purpose.
- Stainless light-medium ~2lb contour intermediate 16" or rifle length 18" for 3 gun
- spr profile rifle length 18" for semi precision/ long range stuff

68Charger
06-25-2014, 18:00
Can you point me at some 24" load recipes? If the 24" vs 20" velocity is negligible then a trip to a smith might be in order....

Yarg!
I don't own a .223/5.56 over 16" currently... and it really depends on the rifle overall- if you're looking for a starting point, look at recipes for bolt guns and heavy bullets (in general, heavier bullets prefer slower powders) even a burn rate chart won't tell the whole story, it depends on many factors.

kwando
06-25-2014, 18:56
I've had 7 in the past and several have just sat... since then i've sold them and only have the following:

1. 11.5" BCM SBR w/ BCM KMR Surefire scout Aimpoint micro (my goto rifle)
2. SCAR 16 pistol with Aimpoint Micro
3. Noveske 16" SS Barrel NSR with Burris 1-4
4. Pistol 10.5" plain jane iron sights w/ M4 handguard

All are outfitted with AAC brakes and can be suppressed when my Stamps are approved.

hurley842002
06-25-2014, 20:58
I only have 1 :(

Don't feel bad, that's where I'm at.

newracer
06-25-2014, 21:30
I have two.

lex137
06-25-2014, 22:16
I only have 1 :(
I only have one too. Thinking of selling the upper for a di one with a 15" KMR rail. I'd say keep the best 3 you shoot also. My 2ยข

hurley842002
06-26-2014, 06:10
I've had 7 in the past and several have just sat... since then i've sold them and only have the following:


Oh, and thanks for parting with the one's that just sat! Lol

T-Giv
06-26-2014, 20:58
Just 1 here now as well. [emoji22]

Erni
06-30-2014, 09:42
Thanks for all your inputs gentleman. Sounds like I am in the ballpark with my choices. I will look at changing the intermediate gun to a 3gun centered setup, and have a hard look at the proper length of barrel required for the long range gun down the road.

USMC88-93
07-01-2014, 19:41
1. 11.5 inch SBR
2. 20 inch A4 with acog
3. KAC SR-25EMC .308

And a spare upper or two one of which is in .22 rimfire.

Most of my preferences have been migrating back to the 20 inch variants as most of my shooting these days is at across the board 200,300. 600 yard matches. The rifle I have that sees the least amount of use is my 9mm Colt 6450 I am thinking about SBR'ing it but wish I could just buy a Colt 9mm factory SBR.