Reference – Viking Armory

Part Polishing Notes

Surface:

Glass Plate as a work Surface, Anything hard and flat

Backing:

Leather

Thin Foam

Straight on the glass surface:

320 takes the longest

400

600

800

On glass surface with foam under sandpaper:

1000

1500

2000

2500

Worksharp:

6000 purple belt

Cordless Dremel;

14000 grit diamond compound

Notes:

It will look like a rainbow, seeing copper and nickle is normal

All Documents posted on this site are for informational use only. If you make ANY modifications to your Weapons based on this site, you do at your own risk! If done incorrectly, you can render you weapon unsafe and / or unusable.

More HERE: https://viking-armory.com/?page_id=723

AR-15 Bolt Carrier Group (BCG) Test Pin Tray

I started working on a holder for the AR15 Bolt Carrier Group (BCG) Pins. The idea came from School of the American Rifle. I wanted to be able to remove the pins if needed. I also did not want to paint my pins for GO / Warn / NO-GO. Here is what I came up with.

Got everything printed up in the right colors and numbers. You can switch it up how ever you like:

AR-15 BCG Test Pin Tray What you print — Everything printed up in the right colors

Then I put it all together. I had to cleanup everything with sandpaper, file and an Exacto knife. With a little help from a small nylon hammer. I got everything in place. Even tried a little infill using model paint.

Added all the pins in:

So far it is working out pretty good. It is another tool in the toolbox when troubleshooting AR15 Bolt Carrier Groups (BCG) The pin sizes are born out of the data I pulled from my research HERE.

Hit us up with comments or questions

More HERE: https://viking-armory.com/?page_id=723

AR-15 Lower Receiver Diagrams – Working Document

Working Document for the Lower measurements. References Below

Receiver Extension Drawing with pin gauging

AR15 Receiver Extension Technical Diagram

Hit us up with comments or questions

More HERE: https://viking-armory.com/?page_id=723

AR-15 Upper Receiver Diagrams – Working Document

I am using this as a working documents to be used as I inspect a rifle.

Hit us up with comments or questions

More HERE: https://viking-armory.com/?page_id=723

Torque Values

My Torque Values:

AR Compensator (Flash hider) No Torque, timing value with the procedure in the Army TM. Hand tight and then tighten a minimum of 90 degrees but no more than 450 degrees to timing. Don’t over tighten, don’t loosen.

AR Barrel Nut 30 Ft. lbs. Minimum, not to exceed 80 Ft. Lbs. to align the next slot in the barrel nut. The 80 Ft. Lbs is not stated in the TM, but I don’t know how you would line up the gas tube, without going over 30 Ft. Lbs. Unless you use shims. I don’t think most folks will have any laying around. This torque spec is common across the community and internet.

AR Carrier Key Screws 50-58 INCH pounds torque

AR Lower Receiver Extension (Buffer Tube/Castle Nut) 40 Ft. lbs for both Rifle and Carbine.

M-LOK Accessories:

For attaching metal accessories to metal hand guards: 35 in/lbs

For attaching polymer or metal accessories to polymer hand guards: 15 in/lbs

For attaching polymer accessories to metal hand guards: 15 in/lbs

The installation torque values are not minimums, they are recommended limits. The nylon patch compound may slightly affect the torque reading if using an in/lb torque wrench.

Using a small hex wrench should prevent over-tightening. Remember that the recoil lugs are doing most of the work, and excessive torque on the nuts is not required

My Comments:

The rest of the items in the research below I could not find in the Army TM, manufacture website or in common reference. Until I can find it, I am going with ‘tight’ and the appropriate thread lockers. ‘Tight’ might be the values listed.

I am not saying that the info below is wrong or bad. I could not readily verify it. The above is what I will use, at the end of the day I am responsible for my decisions and you are responsible for yours.

########### RESEARCH ITEMS BELOW ###########

AR Compensator (Flash hider), 15-20 Ft. Lbs. Torque *1

AR Compensator (Flash hider) *3 (No Torque, timing value)

AR Handguard Screws, 20-30 inch pounds torque *1

AR Gas Block Set Screws, 25-30 inch pounds torque *1

AR Barrel Nut, 30 Ft. lbs. Minimum, not to exceed 80 Ft. Lbs. to align the next slot in the barrel nut. *1 *5

AR Barrel Nut, 30 Ft. lbs. *3 (I cant find the 80 Ft. Lbs. In the TM)

AR Carrier Key Screws, 50-58 INCH pounds torque *1 *2 *3

AR Grip Screw, 15-20 inch pounds torque *1

AR Lower Receiver Extension (Buffer Tube/Castle Nut)

Rifle: 35-39 Ft. Lbs. *1 *3

Carbine: 38-42 foot pounds *1 *3

M-LOK Accessories: *4

For attaching metal accessories to metal hand guards: 35 in/lbs

For attaching polymer or metal accessories to polymer hand guards: 15 in/lbs

For attaching polymer accessories to metal hand guards: 15 in/lbs

The installation torque values are not minimums, they are recommended limits. The nylon patch compound may slightly affect the torque reading if using an in/lb torque wrench.

Using a small hex wrench should prevent over-tightening. Remember that the recoil lugs are doing most of the work, and excessive torque on the nuts is not required

KeyMod Accessories: *1

Polymer to metal: 15 in-lbs

Polymer to polymer: 15 in-lbs

Metal to metal: 30 in-lbs

Picatinny Accessories: *1

Polymer to metal: 15 in-lbs

Polymer to polymer: 15 in-lbs

Metal to metal: 35-60 in-lbs

Ref:

*1 https://www.youtube.com/watch?v=Ah6WISs6IfY

*2 https://www.youtube.com/c/InstructorChad

*3 ARMY TM 9-1005-319-23&P Nov 2008