Pull it down and disassemble bolt and clean carbon out. Lube with Ed's Red (make;it yourself)

Get a 2 gal plastic gas can: Mix as follows:
1/3rd Mercon Dexron Transmission Fluid
1/3rd K1 Kerosene
1/3rd Mineral Spirits (paint thinner).

This should take you to about 50 below zero.

I was a Small Arms and Ammo Test Director at Aberdeen Proving Ground and we found CLP gummed up at about 20 below zero. We tested at 60 below.

For general overall use I use Mobil 1 above.

You may have to soak the bolt and carrier in ER to loosen up carbon deposit on bolt.

UNDER NO CIRCUMSTANCES USE GRAPHITE ! ! !

Last edited by Hummer; 01/31/20.
Formerly Small Arms Test Director, Aberdeen Prov Gnd, Army Small Cal Wpns Lab, Mem Interagency Comm Sec. Equip. Wash, Intl Wound Ballistics Assn, Consultant to INS, USBP, DCIS, FLETC, 4 US Intl Rifle Teams NRA Bene, Vol FD, Eagle Scout, Shriner.