ar question

P

pistol named Bertha

New member
What are the differences begween midlength and carbine/m4 legnth obvious other than one being longer? Is one better than the other? Also if your rifle has standard a2 front sight can you see it in your optics if its a flat top reciever?
 
The length, in myopinion, depends on what the rifle is used for (competiton, duty, ect.) and personal preferance. Get your hands on both styles, either at a gun shop or if you know people that would let you shoot theres and see what you think. My duty rifle (carbine length) is also my competition rifle. I like the way the carbine handles for me and I have had no problems shooting at distance (100yrds ish). Mine does have an A2 type front sight and, yes, I can see it through my red dot, but I like that, it serves as a co-witness to my red dot and doesnt bother me or slow me down during CQB work. Thats my take on it!
 
Mid length gas system offers a smaller recoil impulse giving a more controllable rifle, while giving what some would say a more reliable system. The sight isn't the matter of whether it will be in line with the optic. It's the mount you can choose full co-witness or 1/3 co-witness. 1/3 will allow the sight of the optic to be slightly over the iron sights and not in line with them, although the iron sights are still usable. Full Co-witnessing the optic sight and iron sights will be directly lined up.
 
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I've held and shot carbine lengthand thoroughly enjoyed it. The gun would onky be for self defense and recreational shooting. I don't think I'm going to like tje co witness look.
 
In reallity, gas length is all about 5-7" from the muzzle. That sets the optimum timing.

What happened with "carbine" gas is it was carried over from the M4 and it's 14.5" issue barrel. Even that was optimized to work down to 10" barrels. Once the M4gery market got cranked up, the only way to meet the typical buyers impulse purchasing was to make the barrel length meet the NFA 16" minimum. Most buyers aren't waiting months for an SBR tax stamp.

Carbine gas on 16" isn't best, it's too early, with high gas pressures, excessive bolt carrier speeds, much higher blowback into the action, all due to the early opening of the bolt. It might be milspec, but the industry didn't care for it. They invented "midlength," which put the timing back to the correct point in the gas curve. And footed the cost of midlength handguards.

Some say carbine runs fine, the industry went to a lot of effort and expense to change it, and Uncle Sam wasn't picking up the tab. To me, that means it was saving them money, compared to carbine. Apparently the feedback was hitting the bottom line.

Midlength is correct, and runs better on 16", just as intermediate does better than rifle on 18". AR's don't have an automatically adjusting, expensive valve like semi auto loading shotguns that are forced to fire light bird loads thru magnum goose. They were set up to shoot spec military full power ammo, and there's no wide variety of loads issued. One or two are about it. So, the gas system is set up simple, no complicated valves, and runs reliably so. It's the civilian shooter running low powered import fodder that creates a CS problem. Strangely enough, it runs fine on carbine - less gas works better - but isn't so good on rifle - not enough gas to move things reliably.

Stick to full power ammo with the correct gas, things work, and accept that cheap ammo is just that, not the proper load, a get by.
 
Nothing wrong with a carbine system. Althought i will admit i would never trade my length for one, the only way i would be using a carbine system is in a SBR. Now my friends carbine doesn't have a brake on it so the recoil impulse is a lot more than my rifle. But i have the PWS SM556 on my BCM 14.5" and i can shoot extremely fast while remaining on target. I can't say the same for my friends carbine. Hell his rifle is about a pound or two heavier also because it's the HBAR and it's nowhere near the same. Here's a comparison of mid length braked vs carbine braked.


http://www.youtube.com/watch?v=vWtRyZ9EeSk

To add to Tirod's post don't shot wolf ;) as it's known as low pressure ammunition and if you end up with a mil spec weapon it's not pressured enough for the .062-.063 gas port and will short stroke. I don't like running steel ammo but i have at first and i've had it short stroke in my BCM.
 
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If you liked it, stick with the carbine length. It is a bit easier to maneuver the short gun in the home. I feel that a co-witness to the red dot is important, but not mandatory. I will say that, no matter if you spend 10 or 10,000 dollars on an optic, get a set of backup irons! They make flip up for both front and rear and I feel they are a must have as optics can fail and seem to do so when you need them most! If this happens when the bad guys have kicked in your front door, a quick flip of your finger gets sights on the gun and you back in the fight! Just make sure you spend time shooting with both and take the time to battle zero you iron sights!
 
I have never had a problem with my carbine. Keep it clean, keep it lubed and you will be fine, as long as you dont buy junk, that goes for both gun and ammo!
 
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