Quarterbore's Forums - Ar-15 300-221 Sbr

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Quote:

Originally Posted by HotLead (Post 11767)

http://secure.adpay.com/Images/Items/2100868.Jpg

Offering 2 and 3 position gas blocks for sale.
Requires cutting one inch off your gas tube.
Two position is open and closed or High and low pressure.Three position is closed,low and high pressure.Stainless or parkerised steel.Sizes are .750, .875 .936, and custom
Cost is $60 shipped.Contact tp555@alltel.net or call Paladin Machine at
803-475-7542

(ad copied from Gun Digest online)

I just ordered one for myself in stainless, I cant wait . :grin:

Since I beat Fudmottin to it, here is a pic he posted previously of the block mounted on his barrel:

http://dl.getdropbox.com/u/360586/300-221/IMG_0557.jpg

So its a screw attach gas block .. I am not seeing how this adjusts 3 ways for gas regulation. forgive me. :smile:

The screw is the adjustment. There is a dimple that is hard to see. But it is currently in the closed position. When the notch is vertical, it is in the low pressure (sub-sonic) position. And when the screw is turned 180 degrees from where it is now, it is in the high pressure (super-sonic) position.

The block is held to the barrel by two hex screws underneath the barrel.

It is a solid arrangement. That particular barrel is one inch diameter towards the breach (left) and 3/4 from block to muzzle where it has 5/8-24 threading and a thread protector. It's a 16" barrel made from a Douglas Premium blank with 1:8 twist.

I forgot to mention that the adjustment screw (really a pin) has detents for the three positions just like the selector lever on an M16. So it is held positively in each of the three positions.