Porting a bad idea for a scope on a 16" AR barrel?

[Double Naught Spy]

Gun: Colt AR-15 w/16" HBAR II
Scope: ACOG TA11
Question: In considering having a muzzle brake added or having the barrel mag-na-ported, is there any potential hazards to the scope by either type of muzzle control device? I can't find any information on this and the concern was raised by a buddy who noted I shoulld look into it given that the scope cost more than the rifle.

As a follow-up query, have any of y'all had an AR barrel ported and if so, how well did it work. I understand there are serveral good choices for adding muzzle brakes, such as Kurt's Kustom, so I have found out about a good bit of information on adding brakes, but porting seems more obscure.

 

[AR-10]

The barrel is chrome lined, I would guess. Would the act of drilling ports in it chip the chrome and cause it to start flaking?

The big problem with porting a 16" barrel is the fact that by doing so you will alter the preasure in the barrel forward of the gas block. That may lead to reliability problems. It takes a certain amount of preasure to cycle the bolt. That could be overcome by enlarging the gas port in the barrel.


I don't see how adding a brake, or even porting the barrel would throw significant amounts of gas or particulate onto the lens of the scope you chose. What may be a problem if you port it is the flames shooting out the holes obscuring your field of view. Seriously! My Dissipator has a 16" barrel, and when I shoot it scoped, I can see the fireball momentarily. It is more obvious through the scope than when I am using iron sights. I don't have any sort of muzzle device on the end of the barrel.

 

[George Hill]

Your going to port your scope? Yeah... that's a bad idea.

 

[fastang50]

why?

I have to question the motivation of having the barrel ported, or a compensator installed. I say this because I have one on a 20" AR and I'll tell you first hand that I wish I hadn't had it installed. #1 .223 doesn't recoil enough to matter #2 it's loud as hell #3 it's loud as hell #4 it's loud..... In a 16" bbl it would only be louder, and if you went the magna-port route you'd also loose velocity and risk short cycling the action since gas pressure would bleed off sooner. Just my observations.

 

[JIH]

Porting a chrome-lined barrel is a bad idea, as is cutting on it to shorten it.

If you really desire compensation, put on a muzzle brake.

 

[yankytrash]

JIH - 2 fer 2

Another thing to consider in compensation, especially on the low-powered 223/5.56: in talking to the owner of a local smithing/gun store who specializes in AR-15's and 1911's, he brought up a good point. That is, he bought a bunch of muzzle attachment blanks and designed his own compensator for the AR-15.

In testing, he only loads 1 round at a time. Compensator worked great - he swears you couldn't even feel the recoil. Well, he puts one of the compensators on an employee's AR. Employee comes back the next day and complains that the AR is now a single-shot rifle, not semi. After some head scratching, he found out that the gas was fine, but compensation was so good, in fact, that the bolt would not turn to unlock, an action which requires recoil.

Now, his awesome compensator also requires some minor adjustment to the buffer/spring. Bonus for him, bad for us.

Just thought that was interesting....

 

[Double Naught Spy]

Thanks for the information and especially conerns about how well the gun may or may not work right after porting.

And no, I am not porting the scope and the gun does not have a chrome-lined barrel.

 

[JIH]

Just to reiterate... all things considered, a muzzle brake is your best option. You don't lose any pressure... and with a shorter barrel, you need that pressure.

Also, if the smith just pins and welds the brake (no threading...), if you decide you really, really don't like it, you can take it off and replace it with another. If you port and don't like it, you can cut the barrel (and then you have to put on a device) or sell the barrel (good luck).