I've got a preban with a 10.5 barrel/5.5 flash hider.  Accuracy fine but the noise and weight are becoming a concern. If I got up to a 16 inch will the muzzle blast come down any that I would notice? are should I just stay with what I have? but if I do change I want a lighter barrel my rifle is supposed to be a light weight handy little carbine but it is not much lighter than my ar10.  

Also I've had my ar15 for about 2 years now and have shot several thought rounds threw it(perhaps 2500-4000rds) I really wasn't counting each and every shot.  I shoot almost almost exclusively reloads that I buy from a reloader at the Saxet gunshow in San Antonio and have be happy with their performance at a 100 yards I always get them on target with respectable groups considering my bad eye sight and I use the iron sights.  last year I had a double fire and thought nothing of it I had the rifle range to myself and just assumed that someone on the pistol range behind me had a 44 mag and shoot it a split second after I did.  

But last weekend I'm at the range and had a couple of mags already threw my rifle when I had another double fire. This time me and the guy next to looked at each other and their was no doubt that I had a double fire. This is the second time in a year with maybe a thousand rounds inbetween.  Right now I'm thinking slam fire but my this is somethis else.  Is this something I should have a gunsmith take a look at.  Is my rifle dangerous?

commets please on both questions

The 10 1/2" w/ 5 1/2" FS is a real noisy combo... looks great, but the short barrel is very inefficient... a 16" will be a more realistic and quieter setup... look to Bushmaster for their superlight barrel or have Kurt at KKF reprofile an HBAR to LW specs to keep your carbine lean and mean.

[url]www.ar15.com/forums/forum.html?b=2&f=44[/url]
[url]www.kurtskustomfirearms.citymax.com/page/page/8932.htm[/url]
[url]www.bushmaster.com/shopping/barrel-assemblies/abbl-16sla.asp[/url]

[img]www.bushmaster.com/shopping/barrel-assemblies/Images/abbl-16sla.jpg[/img]

As to your preban doubling, you could have a worn disconnector, hammer, or trigger... change them out.  If your lower has seen a great deal of shooting the problem can also be worn pin holes causing a misalignment, but with the low round count I'd doubt that... change out your fire control components and you're on your way...

Changing out the components is a very simply job.  Replace them with good quality spec parts.  You can get what you need from [url]www.bushmaster.com[/url] and if you've never built from parts before, a great primer can be found here: [url]www.ar15.com/content/docs/assembly[/url]

Believe answer to your question reside here: [b]"I shoot almost almost exclusively [red]reloads[/b] that I buy from a reloader at the Saxet gunshow in San Antonio "[/b]

Occasionally w/ reloads, if the primer is not properly seated you will get a "slam-fire".

While parts do wear, a simple inspection of the brass that doubled, will reveal whether it's part related or a "primer not quite seated flush".

Don't think your rifle needs a gunsmith, as if parts are bad this would be happening more consistently and more often than it has.

No your rifle is not dangerous. (on the other hand who wants a rifle that's NOT dangerous, come to think of it, in fact, all my weapons are dangerous, which is precisely the reason I own them......)

I'd be more inclined to say your ammo choice is dangerous, check your "purchased" reloads carefully prior to firing for primers which are not fully seated and this should minimize your future slam-fires.

If ya find a round which looks suspect, a good way to be sure, is stand round on a flat counter top, if primer is not fully seated, rounds will roll around on the protruding primer, sort of rotating.

Mike

Here is a quick function check for your rifle (or use the one in the -10 if you have it):

1. Unload and clear the weapon and remove the upper from the lower.

2. Cock the hammer in the lower and set the selector to "Fire"

3. Place your hand in front of the hammer to catch it.

4. Pull the trigger to the rear and hold it there, hammer should release.

5. Still holding the trigger to the rear, cock the hammer again with your other hand, it should catch on the disconnector.

6. Release the trigger forward. The hammer should stay cocked.

If the hammer fails to catch the disconnector or releases as the trigger is released, you have a definite problem in your fire control group (trigger, hammer or disconnector).

If it passes this test, then the most likely place to look is improperly seated primers.

Ditto what mr_wilson posted. The reloads are most likely the cause of the doubling.