View Full Version : Barrel for my m4 has to be pinned?
10-12-2011, 5:44 PM
I did a search on the forum to find my answer and could not. I appologize in advance if this has been covered. I recently completed my ca legal ar build. I used a 16 inch barrel. I want to know if the threaded barrel has to be pinned to the upper receiver? I was told it has to be.
I built it using a YM stripped lower with a colt lower parts kit, YM upper, with a YM match SS bolt and a colt style collapsable stock. I also have the prince 50 mag lock on it.
10-12-2011, 5:48 PM
Not unless the barrel itself is less than 16". Then you would need to in order to reach an overall length (OAL) of 16".
Saying this without being 100% certain is a little scary, dont you think?
I recently completed my ca legal ar build.
10-12-2011, 5:50 PM
A 16" barrel is good to go. If it were less than 16" then you'd have to pin the muzzle device in order for it to count towards the 16 inches.
10-12-2011, 6:14 PM
Regardless, you don't permanently (pin) the barrel to the upper receiver. The only thing you would need to do would be pin/weld the muzzle device to a barrel shorter than 16 inches.
I want to know if the threaded barrel has to be pinned to the upper receiver? I was told it has to be.
10-12-2011, 6:19 PM
I was told it has to be.
Please do not pay any further attention to the person who told you this.
I also have the prince 50 mag lock on it.
Which one? The "bullet button", the "convertible", or the one with the allen screw?
The one with the allen screw is outdated and can not legally be used to release the magazine. The only legal way to use that device is to pivot the upper forward and top-load.
10-12-2011, 6:24 PM
Thanks for the replies, it is the mag lock with the allen screw.
But as long as it is locked, would I be able to keep the weapon untill I order a bullet button?
10-12-2011, 6:56 PM
It must remain locked any time the upper is attached to the lower receiver.
When the BB arrives, remove the upper from the lower before loosening the allen screw.
10-12-2011, 9:39 PM
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