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I want to build a shorty AR variant. Either 10.5 or 11.5" system. It will get run with a can, most likely a surefire FA, but would consider a KAC.

Reason for build is the slim to none chance that I'd be able to use it on patrol (and I really want one). I feel an SBR weapon system has a number of advantages over the standard 16" carbine. While I love having a patrol rifle, I think it is still to long to use in many occasions. Clearing a house, or smaller building complex is much easier with a shorty. Plus it is lighter and more nimble (these are reasonable speculations, but haven't done it with a shorty, only with my 16"). It will take me a year or two to get everything put together.


That said, I'd like to try out some shortys before I build, or even plan too far. Would pay for ammo and lunch. Cans are a plus.


Anyone?

I can get you to the range with a 12" if you are in the area. I am allowed to carry a shorty on duty. I have been waiting very impatiently for over three months to make my 870 a shorty. I have purchased the barrel...just need the stamp!

I'll give you a shout on my next houston trip!

You should be a real rebel and apply to carry a short AK with an underfolder.

jbirds1210 wrote:I can get you to the range with a 12" if you are in the area. I am allowed to carry a shorty on duty. I have been waiting very impatiently for over three months to make my 870 a shorty. I have purchased the barrel...just need the stamp!

I hope you don't have the barrel and shotgun in the same place. They can get you for "constructive possession".

Carry-a-Kimber wrote:

jbirds1210 wrote:I can get you to the range with a 12" if you are in the area. I am allowed to carry a shorty on duty. I have been waiting very impatiently for over three months to make my 870 a shorty. I have purchased the barrel...just need the stamp!

I hope you don't have the barrel and shotgun in the same place. They can get you for "constructive possession".

No, I never even picked the barrel up from the gun shop. Seems this thread was good luck as I now have stamp in hand! Time to go see about getting some sights moved around.

Jason

gigag04 wrote:I want to build a shorty AR variant. Either 10.5 or 11.5" system. It will get run with a can, most likely a surefire FA, but would consider a KAC.

Reason for build is the slim to none chance that I'd be able to use it on patrol (and I really want one). I feel an SBR weapon system has a number of advantages over the standard 16" carbine. While I love having a patrol rifle, I think it is still to long to use in many occasions. Clearing a house, or smaller building complex is much easier with a shorty. Plus it is lighter and more nimble (these are reasonable speculations, but haven't done it with a shorty, only with my 16"). It will take me a year or two to get everything put together.


That said, I'd like to try out some shortys before I build, or even plan too far. Would pay for ammo and lunch. Cans are a plus.


Anyone?

I've been wanting a 10.5" (Mk18 Clone) myself for the same reasons you listed above... but I've read that biggest disadvantage is losing significant velocity on 5.56 rounds, rendering the bullet unable to fragment/tumble on impact. Fragmentation, of course, is why the 5.56 platform is so lethal.

So, although you get a much more maneuverable carbine, the loss of fragmentation is almost a deciding factor for me. What do you think, Nick? -- I'm trying to convince myself I need one!

McKnife wrote:

gigag04 wrote:I want to build a shorty AR variant. Either 10.5 or 11.5" system. It will get run with a can, most likely a surefire FA, but would consider a KAC.

Reason for build is the slim to none chance that I'd be able to use it on patrol (and I really want one). I feel an SBR weapon system has a number of advantages over the standard 16" carbine. While I love having a patrol rifle, I think it is still to long to use in many occasions. Clearing a house, or smaller building complex is much easier with a shorty. Plus it is lighter and more nimble (these are reasonable speculations, but haven't done it with a shorty, only with my 16"). It will take me a year or two to get everything put together.


That said, I'd like to try out some shortys before I build, or even plan too far. Would pay for ammo and lunch. Cans are a plus.


Anyone?

I've been wanting a 10.5" (Mk18 Clone) myself for the same reasons you listed above... but I've read that biggest disadvantage is losing significant velocity on 5.56 rounds, rendering the bullet unable to fragment/tumble on impact. Fragmentation, of course, is why the 5.56 platform is so lethal.

So, although you get a much more maneuverable carbine, the loss of fragmentation is almost a deciding factor for me. What do you think, Nick? -- I'm trying to convince myself I need one!

I would think ammo selection will help in this case...
I am sure there's an type or selection of ammo that could offset the loss of fps and the tumble factor.

Here's a list of various velocities recored with barrel lengths from 22'' to 10'' with different handloads in .223.
http://www.accuratereloading.com/223sb.html" onclick="window.open(this.href);return false;
And a separate study.
http://findarticles.com/p/articles/mi_m ... _68704858/" onclick="window.open(this.href);return false;

Carry-a-Kimber wrote:Here's a list of various velocities recored with barrel lengths from 22'' to 10'' with different handloads in .223.
http://www.accuratereloading.com/223sb.html" onclick="window.open(this.href);return false;
And a separate study.
http://findarticles.com/p/articles/mi_m ... _68704858/" onclick="window.open(this.href);return false;

FROM WIKIPEDIA:

This cartridge has a maximum effective range of 550 meters against individual combatants. The 5.56x45mm NATO cartridge with the standard military ball bullet (NATO: SS109; U.S.: M855) will penetrate approximately 15 to 20 inches (38 to 50 cm) into soft tissue in ideal circumstances. As with all spitzer shaped projectiles it is prone to yaw in soft tissue. However, at impact velocities above roughly 2,700 ft/s (820 m/s), it may yaw and then fragment at the cannelure (the crimping groove around the cylinder of the bullet). These fragments can disperse through flesh and bone, inflicting additional internal injuries. Fragmentation, if and when it occurs, imparts much greater damage to human tissue than bullet dimensions and velocities would suggest. This fragmentation effect is highly dependent on velocity, and therefore barrel length: short-barreled carbines generate less muzzle velocity and therefore lose wounding effectiveness at much shorter ranges than longer-barreled rifles. The rapid transfer of energy also results in wounding effects beyond the tissue directly crushed and torn by the bullet and fragments. These remote wounding effects are known as hydrostatic shock.[

I read the webpages you posted and they indicate that the average velocity out of an 8"-11.5" barrel is roughly 2200-2400 ft/s. (Probablly a bit higher 5.56 loads) This is much less than the minimum 2700 ft/s mentioned above for fragmentation. However, even though the velocity was much lower, penetration averaged 4"-5" more than 14.5" - 20" barrels!