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Californio
05-21-2009, 3:37 PM
Exercise is to design a quality sub 6 lb rifle excluding magazine or sling.

Lets call it the Junior Liberty Rifle, a kiss rifle for small youth and petite adult females. Height 4 11 to 5 3 weight 100 to 125 lbs.

Lets use the Colt Model 6520 as a starting point in concept. We know its on the NO, NO list so we are just using the concept. We dont need rails, optics etc., just a simple carbine with iron sights for 100-200 yards.

1. Upgrade the receiver to A3?
2. Upgrade the handguards?
3. Upgrade BUIS?
4. Upgrade the gas system to Mid-length?

So questions:

Anyone make a quality 16 chrome lined 1/7 twist pencil barrel for mid-length gas system?

Smallest dia. Handguards?

Would a A3 receiver with BUIS be lighter than an A2 receiver and a lower site profile?

Please comment.

ocabj
05-21-2009, 3:39 PM
The girls on the California Junior High Power Rifle team are doing just fine with the A2 Service Rifle (NM accurized, of course).

WHenderson
05-21-2009, 4:59 PM
A Colt standard M4 weighs 5.9 pounds. No upgrades necessary. If you use an AR pencil barrel at 16" that would come in at under 6 pounds.
Bushmaster Carbon 15 model 4 is 5.5 pounds.
Vulcan polymer v-15 is 5.6 pounds, which has a HBAR under the handguards.

There's not much design work to do, it's been done. -W
I'm sorry if I'm not participating in your exercise correctly, but I don't think you can get much lighter in a 16" AR.

Technical Ted
05-21-2009, 5:11 PM
Consider that the early AR-15 was chosen by the Military Assistance Program to supply the South Vietnamese Army and their smaller stature soldiers nearly 50 years ago.

Californio
05-21-2009, 5:43 PM
I am looking at getting 11 yearold girls going with training wheels, so to speak. Consider this a Cricket Rifle.

The AR15 has ballooned in weight over the years but the civilian world can make due with a lot less especially in the fun for lb area. Three lbs off the front makes a lot of sense for getting kids interested.

Californio
05-21-2009, 5:44 PM
The girls on the California Junior High Power Rifle team are doing just fine with the A2 Service Rifle (NM accurized, of course).

They are not beginners.

Californio
05-21-2009, 5:51 PM
A Colt standard M4 weighs 5.9 pounds. No upgrades necessary. If you use an AR pencil barrel at 16" that would come in at under 6 pounds.
Bushmaster Carbon 15 model 4 is 5.5 pounds.
Vulcan polymer v-15 is 5.6 pounds, which has a HBAR under the handguards.

There's not much design work to do, it's been done. -W
I'm sorry if I'm not participating in your exercise correctly, but I don't think you can get much lighter in a 16" AR.

The design is trying to spec the best quality parts to duplicate what cannot be bought legally here and ask if a pencil barrel is available with mid-length gas instead of carbine gas.

I assume a legal M4ish (16") will weigh more than 6 lbs.

Would like to stay away from carbon/polymer.

Standard receivers:)

What did an old civilian CAR weigh 5.5 lbs?

ocabj
05-21-2009, 5:52 PM
They are not beginners.

Some are. And everyone from marksman to high master pretty much started out on the full 20" A2 SR platform. If anything, the A1 stock can be used to shorten the length of pull, but I doubt it will be necessary.

But if you absolutely need a sub-6lb rifle, go with the 16" lightweight contour with an M4 4position stock. I don't think the kids will appreciate the shorter sight radius, though. Also, a collapsible stock like the 4-position CAR style stock doesn't lend to good cheekweld habits.

Technical Ted
05-21-2009, 6:12 PM
The design is trying to spec the best quality parts to duplicate what cannot be bought legally here and ask if a pencil barrel is available with mid-length gas instead of carbine gas.
CMMG makes 14.5", 14.7" and 16" lightweight profile barrels with mid-length gas systmes. The 14.x" barrels would need a permanently muzzle device to make them legal length.

THe 14.5" barrel will shave a few ounces off the total weight. Personally I prefer how a 14.5 with a permanent Vortex or Phantom handles in tight spaces--16" barrels with muzzle devices seem long in comparison.

Go with the carbine gas system and the handguards are shorter, thereby shaving an ounce or three.

Install that on an A1 upper receiver (to KISS) with standard tapered handguards. Use an older/original Colt A1 receiver without brass deflector (Newer "A1" receivers with the brass deflector were introduced by Diemaco for the Canadian C7 rifle).

A collapsible stock allows adjustment for shorter arms.

Californio
05-21-2009, 7:54 PM
CMMG makes 14.5", 14.7" and 16" lightweight profile barrels with mid-length gas systmes. The 14.x" barrels would need a permanently muzzle device to make them legal length.

THe 14.5" barrel will shave a few ounces off the total weight. Personally I prefer how a 14.5 with a permanent Vortex or Phantom handles in tight spaces--16" barrels with muzzle devices seem long in comparison.

Go with the carbine gas system and the handguards are shorter, thereby shaving an ounce or three.

Install that on an A1 upper receiver (to KISS) with standard tapered handguards. Use an older/original Colt A1 receiver without brass deflector (Newer "A1" receivers with the brass deflector were introduced by Diemaco for the Canadian C7 rifle).

A collapsible stock allows adjustment for shorter arms.

Thank You

kermit
05-22-2009, 12:51 AM
The old M1 Carbine is about 5.2 lb and has iron sights, light recoil, small size, and they could shoot in some of the CMP matches if they become really interested. They are relatively easy to shoot but may not be as accurate as the AR-15 platform.