Polytech M14 flash hider

[DD977GM2]

I have a polytech M14 (M1A) rifle. It is a tack driver and shoots better then I can. Yeah Yeah I know its not a Springfield or whatever, I got it in a trade and got a decent deal out of the trade.
My question is, the muzzle break is just that, a muzzle break and not a flash hider and I want to take a die grinder to the grooves that would facilitate the flash hider openings. I know I can cut out the slots and make it look decent, but for those in the know, would this work the way I am wanting? I dont really want to spend the $70 + shipping to get a Fulton Armory flash hider and then send the receiver to someone to have it aligned properly etc. Money is tight and yet I want the wonderful advantage of the flash hider.

Anyone ever do this or heard of anyone?

Any logical advice would be appreciated. [M2]

[GunTroll]

I would think you can pull it off if your capable that is. If your competent then go ahead. I'm not 100% sure of the aligning issue your talking about. I just changed one out on a Springfield and aligning wasn't an issue. The castle nut just tightens it up and there are some "grooves" on the barrel that keep it straight during the install. I haven't worked on a poly but thats my understanding on the SA ones. I'm sure you know this but I would take the old one off and then do the work. Get a castle nut wrench for this job ($14ish from Brownells). Get those burrs off of the inside and I again....would think you'd be just fine. If you don't want to spend the green for a new one.....then do forward with your plan.

[Birddog1911]

I'm not familiar with a Poly, but your alignment splines should not be an issue with a new flash hider. If they are not in proper alignment, then you have bigger problems.

Without seeing your muzzle brake, I hesitate to say about grinding flash hole grooves. Too easy to muck things up. As long as your splines are in proper alignment, it is just as simple as buy new flash hider, remove old setup, and put on the new one. Could you supply photos of your rifle for clarity?

[GunTroll]

I know what he's talking about as far as the brake goes. I got one in my shop at work. Its like they cast the part or something but didn't mill out the ports. They are in place but just not cut. Cheaply made.

[Troublco]

They are cast. You can find them with and without the slots in them. Another option might be to find another Polytech cast unit that does have the slots in it, as it would save you a bunch of work. I've seen them for around $30-$35 on the M14TheFiringLine Forum.
Otherwise, I'd think you could cut some sort of slots in one and have it be functional. Unless you had a mill cutter with a similar profile as was used for the originals (and copied by polytech) I would think it would be difficult to match the ports, but if you were careful I think you could cut some usable slots in the depressions. I think I'd find a way to try to cut them with a wheel of some sort, with the flashhider in a vise. That way the wheel would sort of self-guide if you were careful.
For the alignment issue, if you don't have skidmarks on the inside edge of the business end of the flashhider you probably don't have alignment problems. You can make a tool to check the alignment by taking a piece of metal rod about 8-12 inches long, wrapping a bit of electrical tape in three spots to build it up close to bore size (one at one end, one 3-4 inches away from that, and then one that much further again) and then carefully guiding the first wrap into the muzzle. Go until the first two wraps are in the rifling and the third is right in the end of the flash hider. See if the wrap in the flash hider end is contacting any portion of the flashhider. If it there's no contact all around the end, your alignment (assuming the rod is straight) is fine even if it's not perfectly centered. You can also use a brass rod that would just fit into the barrel rifling; you can usually find these at hobby and hardware stores. I've heard of people shooting M14's with out-of-alignment flash hiders, and they wind up with lousy accuracy and eventually a cracked flash hider. Probably sooner with a cast unit.
The M14TheFiringLine forum has a ton of good info on M14's, including the Polytechs and Norincos. One thing to keep in mind - some of the parts are NOT interchangeable between the Chinese and the GI/US guns. Like the bolt, for example.

[DD977GM2]

Here are some pics of the flash hider. My worry is aligning the sights properly if I took the flashider off. I have read(probably drunken reading) and there is an alignment issue when you replace or take off the flash hider. Pleas o please correct me if I am worng. Im not sure if this is a rumor or a legit concern when taking the flashhider off.

[Troublco]

You shouldn't have a big issue with sight alignment reinstalling the flash hider/sight assy. as they have splines to align them. Once you have reinstalled the flash hider/front sight assy and properly snugged the castle nut there shouldn't be any play; it should be about where it was when you took it off. The splines should be snug enough that the front end won't just fall off; you'll probably have to gently tap it with a soft face hammer as you loosen the castle nut, at least to start.

Also, FYI, there's a small set screw that locks the castle nut in place; be sure to loosen it before you try to loosen the castle nut.

[DD977GM2]

Thanks Trouble. I appreciate the advice and insight![Beer]


You shouldn't have a big issue with sight alignment reinstalling the flash hider/sight assy. as they have splines to align them. Once you have reinstalled the flash hider/front sight assy and properly snugged the castle nut there shouldn't be any play; it should be about where it was when you took it off. The splines should be snug enough that the front end won't just fall off; you'll probably have to gently tap it with a soft face hammer as you loosen the castle nut, at least to start.

Also, FYI, there's a small set screw that locks the castle nut in place; be sure to loosen it before you try to loosen the castle nut.

[theGinsue]

Wow. Thanks for the pics. Why on earth would they not just cut those slots out? Sounds like they took a cheap shortcut on this one.

[Circuits]

It was actually an import issue. The early ones were too evil so Polytech left the slots solid on later ones and Mr ATF man was happy again.

[10x]

If you are not out of alignment now, you won't be after you cut the slots.

The alignment comes from the base of the opening in the muzzle break/flash hider butting up against the square face near the muzzle. The splines help keep things aligned, otherwise just eyeball it and you can tell. You can use shims on those faces to change the alignment. National match flash hiders are opened up a little to avoid the bullet contacting the hider.

Don't get the metal too hot when grinding.

The ATF did not allow import of some guns because of features. The muzzle break was one way to avoid a disqualifying feature.

[bryjcom]

Take it off and machine away. You don't need to send it to get aligned unless it doesn't align its self. I quick eyeball down the muzzle end and go shoot it a couple of times. If its hitting the hider than you will see copper marks on the inside of the flash hider.