How do I clean the gas valve assembly on my 391 Urika / Teknys?

Make sure the firearm in unloaded and follow basic safety rules before performing any procedures.

The gas valve system should be cleaned every 3,000 to 5,000 rounds based on the type of ammunition used or at the end of the season when the shotgun will be stored for extended periods.

Gas system overview. Please see the illustration below.



Only use the supplied hook wrenches to remove or tighten the lock nut and counter-nut. These wrenches are designed with the proper dimensions to provide the correct driving torque to properly tighten the nuts. Use other tools may cause damage to the gas system components. 

1) Remove the barrel as outlined in the manual.

2) Using the supplied hook wrenches, loosen and remove the first lock nut by turning it counter-clockwise as shown below.





3) Loosen and remove the counter-nut by turning it counter-clockwise with the hook wrench as shown below.





4) Disassembled parts layout shown below. 



5) Clean these areas using Beretta oil and then dry the parts. For cleaning suggestions, please visit our Ask Us A Question webpage and enter the number 170 in the search text field, and change the search by field to answer ID.

Cleaning illustrations available online at http://www.berettasupport.com/apps/391/gas.assy4.jpg, and http://www.berettasupport.com/apps/391/gas.assy5.jpg, and http://www.berettasupport.com/apps/391/gas.assy6.jpg

6) Install the gas valve shaft with the hood towards the barrel.  Illustration available online at http://www.berettasupport.com/apps/391/gas.assy7.jpg

7) From the front of the gas cylinder and in this order, slide the centering ring, gas valve with the dished side towards the gas spring and gas spring over the valve shaft. Screw the counter-nut down until it is snug. Leaving the counter- nut loose or backed off a few turns will cause cycling problems!  Illustration available online at http://www.berettasupport.com/apps/391/gas.assy8.jpg

8) Install and tighten lock nut. Illustration available online at http://www.berettasupport.com/apps/391/gas.assy9.jpg