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kisskaren
07-09-12, 15:35
Hi, I did not find any similar questions, After learning this video
http://www.youtube.com/watch?v=dWzs9JA4U4w

I am trying to install my SureFire FH556-212A flash hider, please check the pics A and B, I don't understand which side of the washer, should be face to the rear (bud-stock direction).

12789
12790
buckjay
07-09-12, 17:57
The thin one is a shim, it doesn't matter which direction it faces. If the thick one is the shim in the kit, I don't think it matters either.

Just screw on the FH, take a look at where it bottoms out and use the timing wheel to figure out how much you need to shim it back so it bottoms out in the right spot (the bottom notch should line up at around 5 oclock).


Good luck!
Duffy
07-09-12, 18:21
Any palm reader here? :D

I usually see the wider part of the crush washer facing the muzzle, but have installed it both ways, could be just an aesthetics preference.
kisskaren
07-09-12, 18:49
Thanks for the reply.
The above two pictures are showing the washer's two side. The package include one washer, several shims and a rocksett. I have to put on the washer, screw the flash hider first, check the timing, and then add shims.
bp7178
07-09-12, 20:15
The washer with the bevel isn't a crush washer or anything like that. It serves as a spacer for barrels which don't have a releif cut at the base of the threads. The beveled side, shown in the top pic, would go toward the base of the threads/barrel shoulder.

The colored end goes toward the muzzle device.
kisskaren
07-10-12, 00:10
The washer with the bevel isn't a crush washer or anything like that. It serves as a spacer for barrels which don't have a releif cut at the base of the threads. The beveled side, shown in the top pic, would go toward the base of the threads/barrel shoulder.

The colored end goes toward the muzzle device.

GOT IT! Thank you very mush sir!!!!
ddnguyen9
07-10-12, 01:17
I know I am kind of late to post this but I installed a FH556-212A on my M4. I installed the orange side of the spacer to face toward the your targets and the beveled side faces you. Good luck!
oddballmkg
07-10-12, 01:24
I find its easier just to install the flash hinder by first just threading it on with the bevel washer by hand until it stops against the barrel. Then just unthread the flash hinder until it aligns up and down correctly. If the gap is too small, back it out one more turn. Then using the shims in the kit, measure the gap between the washer and flash hinder. Then using the chart they give with the instructions, adjust the shim thickness by adding in .002" to .003" to your shim thickness you measured. The flash hinder only needs to turn about 1/16 of an inch to reach the torque value they call out in the instructions. I've installed 4 of flash hinders this way and its the easiest way I've found to do it.
bp7178
07-10-12, 09:35
That really doesn't sound any easier than using the color chart and a torque wrench.
oddballmkg
07-10-12, 19:23
I find when I follow Surefire's instructions, I end up having to remove and retry the shimming 3 to 4 times until I get the right combination of shims that allow the flash hinder to be clocked correctly. With doing what I described in the above post, it usually takes me one try to get it right. I have to witness a lot of shimming installations at work, you would not believe how many shims are used in building of airplanes. This is why I find it faster to do my method than using their installation instructions.
bp7178
07-10-12, 22:46
I've never had too much trouble shimming with Surefire's chart.

They give you that point on the chart you're suppose to be aligned at prior to torquing. I always aim for the inside of this, between it and 6 o-clock. Its almost as if the start point prior to torque should be a little more toward 6 o-clock.

Either way, its a flash hider not a space shuttle. The chart works. I wouldn't go out and buy a set of feeler gauges for it. If I had a set lying around...