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7/16/2003 12:00:45 PM EDT
What does the sear block do?  I've seen rifles for sale that say they've had the sear block removed and I've seen some that say they still have the sear block.  I'm a little confused.  Is one more desirable than the other and why?  Thanks.
7/16/2003 1:05:40 PM EDT
[#1]
The sear block is just that...it physically blocks the installation of an auto sear - which is what allows an M16 to go full auto or burst.  Unfortunately, it also tends to block the installation of most aftermarket trigger assemblies.

I'd say the value between the two would be six one way, half dozen to the other.  Most of the rifles with the bocks also had the larger pin holes which also doesn't allow for the installation of most 3rd party trigger assemblies.

Hope this helps!
7/16/2003 1:07:06 PM EDT
[#2]
For a while, Colt was installing a steel block in the lower with 2, and later 3 blind-pins.  This was to prevent the installation of either a USGI-type auto-sear OR a Drop-In Auto Sear (DIAS).  Essentially, it was strictly a "PC" move on their part.

[img]photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=9698[/img]
Colt "Sear-Blocked" lower


[img]photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=9700[/img]
M16 lower with auto-sear for comparison.


An unblocked lower is definitely more desireable.  The block not only prevents the use of standard carriers, but also prevents some aftermarket triggers from being installed.  It *is* legal to remove the block, but you'd want that done by someone with experience doing so, and have the pin holes filled in.

-Troy
7/16/2003 2:35:53 PM EDT
[#3]
Master Troy,

Now looking at my AR. I have the sear block, but the diameter of the sear pin that goes through it, is the same size of the "Hammer And Trigger Spring" pins. What does this tell me? Can I take out the sear block to put in a different bolt carrier?

Thank You.
7/16/2003 6:09:54 PM EDT
[#4]
Hey Troy ! I'll trade ya a shiny new BLACK lower for your dingy, old GREY one!!
7/16/2003 6:24:38 PM EDT
[#5]
Quoted:
Hey Troy ! I'll trade ya a shiny new BLACK lower for your dingy, old GREY one!!
View Quote


You'd do that for me?    What a pal!

[;D]


-Troy
7/16/2003 6:28:13 PM EDT
[#6]
Quoted:
Master Troy,

Now looking at my AR. I have the sear block, but the diameter of the sear pin that goes through it, is the same size of the "Hammer And Trigger Spring" pins. What does this tell me? Can I take out the sear block to put in a different bolt carrier?

Thank You.
View Quote


Any sear block can be legally removed without a problem.  Physically removing it is much more of a problem, though, as Colt installed them with blind pins so that you can't just remove it.  Kurt at KKF is experienced at machining them out and filling in the remaining pin holes with black Delrin rod.  Once the block is removed, any carrier would fit.

-Troy
7/16/2003 6:32:11 PM EDT
[#7]
Thanks Troy!

I owe ya a cold beer!
7/17/2003 1:26:21 AM EDT
[#8]
They’re also a pain in the butt to clean around…
7/20/2003 9:50:37 PM EDT
[#9]
Troy IM or email me with contact info for Kurt at KKF if you would. I'm looking to have the same thing done to install a KAC set up.

Thanks
Jeff
7/21/2003 5:20:40 PM EDT
[#10]
Kurt has a forum in the Industry section...

-Troy
7/21/2003 7:13:58 PM EDT
[#11]
So THAT'S what the little piece is that you see all the time on Ebay described only as a "Colt Rare Surplus Part" ![;)]
[img]http://images.auctionworks.com/hi/51/50563/sear-2.jpg[/img]
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