24" AR only cycles on heavy grain rounds..

[BigBuckeye]

Guys,

I just built a 24" AR with a Wilson Bull Barrel, all the rest is Rainere Arms. It won't cycle or feed properly on 55 grain 223, but it cycled fine on 70 grain. Is this a result of the added barrel length or do I have a problem?

[tom12.7]

How about some more specifics on the ammo you are running and the rest of the rifle?

[The M]

Rifle gas system? Which buffer? Which buffer spring? M16 bolt carrier?

[BigBuckeye]

What information would be helpful?

[tom12.7]

Exactly, what ammo are you shooting? What gas system? What buffer system? What buffer?
There's more that could help, but that would be a good start.

[The M]

What information would be helpful?

The four items that I listed in the previous post would be quite helpful.

[Scorpion]

At 24", it is most certainly a rifle gas system, which means that it most likely has a rifle buffer and rifle action spring, unless he is using the A5.

To OP: By "built", did you assemble it yourself or just put an upper on a lower? What kind (brand) of ammo were you shooting?

[tom12.7]

There's a lot of 24-26" with extended +2" rifle gas systems that are ported too small for anything but hot ammo. Also, there's many that use carbine REs. While this combo sounds weird, it's common with varmint shooters.

[Iraqgunz]

55gr. ammo is generally much hotter than most heavier loads. There has to be something else happening. Since we have almost no details it's hard to know.

There's a lot of 24-26" with extended +2" rifle gas systems that are ported too small for anything but hot ammo. Also, there's many that use carbine REs. While this combo sounds weird, it's common with varmint shooters.

[tom12.7]

Very true, there's no telling with the info provided. His 55gr maybe 5 year old PMC .223 bronze that was notorious for choking 20" rifles for all we know. Let's see what info the OP can supply us with.