Rail cracked... ?

[Pyzik]

UPDATE on page 2

So, I added this rail about a month ago. Haven't even had the rifle out yet.
Today a friend stopped by who just got his first AR and I was showing him mine when I noticed this...

https://lh3.googleusercontent.com/-FwofvPllIVY/U3j7-eWzi2I/AAAAAAAABgM/mnJFDkqgcGw/w868-h577-no/DSC_0334.JPG

https://lh4.googleusercontent.com/-NlRJemYi2XE/U3j8K3Wea1I/AAAAAAAABgc/716kcd_bf1M/w868-h577-no/DSC_0338.JPG

https://lh5.googleusercontent.com/-HPVuz1cCho4/U3j792j3NVI/AAAAAAAABgI/ZpDu6iTRb7A/w868-h577-no/DSC_0335.JPG

https://lh5.googleusercontent.com/-ISjp4vvV_dE/U3j79gcMzjI/AAAAAAAABgA/vJ3ezshj8zg/w868-h577-no/DSC_0336.JPG

https://lh5.googleusercontent.com/-pvh4EfkKWN8/U3j8J0x_dnI/AAAAAAAABgU/CQ-uQow9bFs/w868-h577-no/DSC_0337.JPG

https://lh3.googleusercontent.com/-uwh-VWFGUr8/U3j8Nyxhx6I/AAAAAAAABgk/tLqmDRT-wCA/w868-h577-no/DSC_0339.JPG

Anyone have any idea of how this could have happened? The rail has seen no action.

It looks like some kind of corrosion.

[UWone77]

Samson rail?

Was this rail new or purchased used? Hard to imagine how that could have been cracked like that just sitting in the safe.

[FortTom]

So, I added this rail about a month ago. Haven't even had the rifle out yet.
Today a friend stopped by who just got his first AR and I was showing him mine when I noticed this...

https://lh3.googleusercontent.com/-FwofvPllIVY/U3j7-eWzi2I/AAAAAAAABgM/mnJFDkqgcGw/w868-h577-no/DSC_0334.JPG

https://lh4.googleusercontent.com/-NlRJemYi2XE/U3j8K3Wea1I/AAAAAAAABgc/716kcd_bf1M/w868-h577-no/DSC_0338.JPG

https://lh5.googleusercontent.com/-HPVuz1cCho4/U3j792j3NVI/AAAAAAAABgI/ZpDu6iTRb7A/w868-h577-no/DSC_0335.JPG

https://lh5.googleusercontent.com/-ISjp4vvV_dE/U3j79gcMzjI/AAAAAAAABgA/vJ3ezshj8zg/w868-h577-no/DSC_0336.JPG

https://lh5.googleusercontent.com/-pvh4EfkKWN8/U3j8J0x_dnI/AAAAAAAABgU/CQ-uQow9bFs/w868-h577-no/DSC_0337.JPG

https://lh3.googleusercontent.com/-uwh-VWFGUr8/U3j8Nyxhx6I/AAAAAAAABgk/tLqmDRT-wCA/w868-h577-no/DSC_0339.JPG

Anyone have any idea of how this could have happened? The rail has seen no action.

It looks like some kind of corrosion.

I don't think it's corrosion. It looks like the crack caused the rail to push up on the "stress fracture" looking section. Now, what caused it to crack? I think it would take a heck of a smack on something to break the bottom, causing the upward force that caused the "fault" just above it. I'm with UWone77 on this one. Either came from factory like that, or possibly fell in safe?

Another possibility was that there was a fault in the rail from the factory, and it only took a minor "bump" or whatever to expose it. I would contact the manufacturer, as with that type of fracture, we can guess all day what caused it. Maybe they'll just let you send that back and send you another.

FT

[Pyzik]

The safe is packed full, there is no way it could have tipped over in there. Haha

I did lean it against a chair a couple days ago and it tipped over onto carpet with padding. It couldn't have cracked from that.
Perhaps there was a hairline crack that was unseen...?
Then the tip over was just enough to cause it to let go?

I don't know if Samson will do anything. I bought it from John using Rovolvr, it was a take off from an Adams Arms.

[UWone77]

I guess the question really is... Did you notice or was the rail damaged before you installed it?

Either way, I'd contact Samson and ask them if that's damage they've seen before, doesn't seem to me that it would crack just based on dropping it on a carpeted floor.

[Pyzik]

I'll email them and see.
I looked over the rail pretty good when I received it. It looked new.

[Soisauss]

I guess the question really is... Did you notice or was the rail damaged before you installed it?

Either way, I'd contact Samson and ask them if that's damage they've seen before, doesn't seem to me that it would crack just based on dropping it on a carpeted floor.

either that or shipping damaged. I agree with UW, is called Samson about it. Fairly sure they'll gladly help you out.

[Slippers]

If it wasn't subjected to a serious amount of force after manufacturing, it might be a flaw in the original extrusion.

[GOST]

I think Pyzik's hands must apply the pressure equivalent to the jaws of a pitbull.

[Pyzik]

Thanks for all the info guys. Sent Samson an email last night.
I'll update with their response.

GOST, closer to an Alligator Snapping Turtle maybe... :D

[RiverRat]

https://lh3.googleusercontent.com/-uwh-VWFGUr8/U3j8Nyxhx6I/AAAAAAAABgk/tLqmDRT-wCA/w868-h577-no/DSC_0339.JPG
It looks like some kind of corrosion.

Corrosion is very unlikely, there is no electrochemical potential in that location (no dissimilar metals in contact).

I'm trying to be completely objective, not making any accusations, but this looks like damage from impact with the FSB.
- the damage is shaped looks like shear damage - its a straight line. Stress fractures around inclusions wouldn't look like that either.
- the location of the damage seems to correspond with the rear edge of the FSB.
- the fold on the bottom of the "S" could be explained by deflection of the cracked upper edge radially outward and shows normal "squiggly" stress fracture from deflection.
- the FSB itsefl seems to have some impact damage

Note: if the silver shadow in the photo above is the gas tube, it looks like it is severely jacked up. Is the FSB an Armalite clamped version and did it rotate on impact? Otherwise, it's possible that the rail itself moved and bounced off the FSB when dropped. Either way, my opinion based on the narrow-depth of field photos supplied is that this damage isn't a manufacturer's defect. Sorry.

[Pyzik]

Corrosion is very unlikely, there is no electrochemical potential in that location (no dissimilar metals in contact).

I'm trying to be completely objective, not making any accusations, but this looks like damage from impact with the FSB.
- the damage is shaped looks like shear damage - its a straight line. Stress fractures around inclusions wouldn't look like that either.
- the location of the damage seems to correspond with the rear edge of the FSB.
- the fold on the bottom of the "S" could be explained by deflection of the cracked upper edge radially outward and shows normal "squiggly" stress fracture from deflection.
- the FSB itsefl seems to have some impact damage

Note: if the silver shadow in the photo above is the gas tube, it looks like it is severely jacked up. Is the FSB an Armalite clamped version and did it rotate on impact? Otherwise, it's possible that the rail itself moved and bounced off the FSB when dropped. Either way, my opinion based on the narrow-depth of field photos supplied is that this damage isn't a manufacturer's defect. Sorry.

What you're seeing in the photo is the taper of the (light weight) barrel, not the gas tube. The upper is a BCM 14.5 LW purchased as a complete upper. That is a pinned FSB.
My upper has seen a fair amount of use and does indeed have mars and the finish is wearing which you are seeing. I had a MOE handguard set on the rifle before the rail so the FSB was "exposed" to wear.

There is no possible way I could have caused trauma significant enough to cause the cracking. That's why I was wondering about corrosion.


ETA: Samson got back to me this morning but for some reason could not view my pics. Re-attached and am waiting on their reply. I will say they got back to me pretty quickly.

[Pyzik]

Well, they are very quick.


Yah that is strange that it broke. We will replace it if you want. Let me know and ill send you the RMA form.

Thanks,

Andrew Dreher

[GOST]

Can't beat that service.

[RiverRat]

Pyzik -

Thanks for the response - yeah, I can see now that the shadow is the barrel, I brain farted on frist glance - thanks for clearing that up and confirming its a pinned FSB.

No matter what the cause of failure was, it's cool that Samson responded so quickly and is replacing the rail for you. Yet another data point showing they're a great company.

Glad things worked out.

[Pyzik]

Well, this FSB is much harder to pound off with this rail on that it was with no rail on... Whew.

Anyone have a secret to make this process easier? I am just using a hammer and punch.
I don't have an arbor press but have access to one. Though I am worried about putting pressure on this rail and causing further damage.

I did let some PB Blaster soak in over night.

[Pyzik]

UPDATE:

Well I took the rail to ATEi and Doug helped me get it off.
Shipped it off to Samson and get a new one back in exactly one week. They even threw in a couple extra accessory rails.

Re-installed it last night and am back up and running.

+1 to Samson.

[tappedandtagged]

UPDATE:

Well I took the rail to ATEi and Doug helped me get it off.
Shipped it off to Samson and get a new one back in exactly one week. They even threw in a couple extra accessory rails.

Re-installed it last night and am back up and running.

+1 to Samson.

Good deal! Glad to hear Samson took care of you (not surprised, but still glad to hear it).

[UWone77]

I usually let the pins soak in some Kroil first, then use the Brownells cutout for the FSB to hammer it out. Some pins are just basically impossible to move in my experience. Not an exact science.