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United Defense Labs. .750 Adjustable Gas Block
United Defense Labs. .750 Adjustable Gas Block

United Defense Labs. .750 Adjustable Gas Block

On sale: $49.99 $8.99
Retail Price$49.99
You Save:$41.00(82%)
Part Number: GB-50391-SB
Availability: In Stock.
United Defense Labs. .750 Adjustable Gas Block

Special Buy Item - Coupon Codes Not Valid With This Product

The United Defense Labs .750 Adjustable Gas Block is designed to fit under most manufacturer's free float handguards. Adjustments are made via a 5/64 set-screw and a 5/64 retaining screw ensures the system remains locked, no need for thread locker.

What you want to achieve is a rifle that functions correctly with the proper amount of gas pressure.

This is done by adjusting the amount of gas into the system. When this is done it should be with the actual load you plan on shooting. Too little pressure going through the system and the rifle will not be reliable and too much will cause excessive recoil and could damage your rifle.

The adjustments must be done in a safe area following all safety rules. "Make sure that the firearms is completely unloaded"

1.We are assuming that you have the gas block installed, properly aligned with the barrel gas port and the gas tube properly installed with the gas block tightened in place.
2.Once this is done loosen the front set screw, then turn the adjustment screw on the side in until the screw stops (no not over tighten). This will restrict the gas to going to the gas tube all the way down.
3.What you want to do now is shoot the rifle at a safe location in a safe direction with 1 round in the magazine. The round should fire and not lock the bolt back. This is because there is not enough gas to properly extract, eject and lock the bolt back.
4.Now turn the adjustment screw 1 full turn out. Fire the rifle again with 1 round in the magazine.  Continue this until the bolt locks open. Once it locks back this is the point where you have enough pressure to function the rifle.
5.Now back the adjustment screw out 1/2 turn more, then tighten the front set screw. This will lock the adjustment screw in place.
6.Now test the rifle with 10 rounds making sure it ejects and functions correctly and locks the bolt when empty.

You may be done now or you may need to allow a little more pressure. If you do adjust, do so at 1/2 turn increments. Remember to loosen the front set screw first and re-tighten after.

We always recommend that this be installed by a professional gunsmith.

CNC machined 4140 chromoly steel
Full shutoff with zero adjustment movement
Nitride/Melonite QPQ finish
Fits under most free float handguards
Internal Diameter 0.750
Includes (2) set screws for a secure attachment
Includes a 5/64" Set-Screw and a 5/64" Retaining Screw (Rearward facing)
Accepts standard gas tube roll-pins but, a roll-pin is NOT included.
Clamp set screws are 3/32

Please note: If the listing says "In-Stock" it means we have all of the items in stock. Please check this LINK to view our most up to date shipping status. 
Warranty, Returns & Terms:
Davidson Defense offers a 30 day return, refund and exchange policy. You must email or call Davidson Defense and obtain an RMA number prior to any return, refund, or exchange. All returns must include the original order number, receipt or invoice, along with the billing address, shipping address, contact phone numbers, contact emails, and RMA number. Returns, refunds, and exchanges may take up to two weeks, not including transit times, for processing after we receive it. Return shipping costs will be the responsibility of the returning party, with the exception of the wrong item being received or on warranty exchange during the first 30 days after delivery. Items returned for warranty will only be replaced or exchanged, not refunded.

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