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batsoff
10-13-11, 23:12
Please forgive the newbie question... is it normal for the FSB to have a little side to side movement? I just noticed that I can move mine a few mm from right to left.

I was always under the impression that the FSB was staked so that there wouldn't be any movement?

It's not something I'm terribly worried about, just curious if it's normal.

-batsoff

ucrt
10-13-11, 23:19
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If the pins are not hammered in all of the way, it might move...that is if it has pins. Is it pinned or does it have set screws?

If it has pins, drive them in all of the way. Any pictures?

.

batsoff
10-15-11, 09:30
The pins are hammered in, they look like they are set ok.

It's a DD rifle, M4 V3 LW.

I didn't notice the movement when I first picked up the rifle, but after a couple of hundred rounds downrange, I've noticed a little side to side movement.

Thanks for your reply!

-batsoff

5pins
10-15-11, 11:23
There should be no movement at all with the FSB.
How are you checking for movement? If you are grabbing the rail with one hand and the FSB with the other then there will be some flexing.

ucrt
10-15-11, 12:09
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I'd give DD a call.
They're great. I had a non-gun issue once and they impressed the heck out of me by the way they handled it.

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Quiet-Matt
10-15-11, 12:26
I have a DD barrel with factory pinned front sight. They ship without the pins hammered in, just slid in place to hold everything together. That way you can change things if you desire, prior to setting the pins. So, when I initially configured the carbine I set the pins for the first time. Later I changed the HG and had to remove the front sight to do so. I re-assembled using the same taper pins and the front sight had the same slight side to side play that you describe. After knocking the pins back out I used calipers and a straight edge to check for deformation of the pins. They were indeed deformed at both ends with the center a smaller diameter. Installation of new taper pins fixed the issue and served as a lesson learned. I don't know if DD's pins are soft or what, but from now on I'll use new ones whenever I have to mess with them.

OLD...
https://lh5.googleusercontent.com/-_BvRd-JYJgs/Tpm_pUFiIZI/AAAAAAAAJDs/opFf3iug1H8/s940/DSC02615.JPG

NEW (on left)...
https://lh6.googleusercontent.com/-ZIfgcE6wK4Y/Tpm_qsrC93I/AAAAAAAAJDw/GH8e0s3EE-4/s968/DSC02616.JPG

-Matt

Javelin
10-15-11, 12:57
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I'd give DD a call.
They're great. I had a non-gun issue once and they impressed the heck out of me by the way they handled it.

.

Totally agree. Call DD and see what they say.

Iraqgunz
10-15-11, 17:36
Please contact DD about this issue and then get back to us.