Category Archives: gunsmithing


The Beretta Model A303 is a semiautomatic shotgun that is fed by a tubular magazine.

gunsmithing note(s):

      • A303 barrels made prior to 1994 are soft soldered. A303 barrels made in 1994 and after are silver soldered.1


Bravo Company MFG

Bravo Company MFG, also known as BCM, is a manufacturer of AR platform parts located in Hartland, Wisconson.

gunsmithing note(s):

      • When rifles are assembled by BCM, extreme heat must be used to release the gas block retaining screws and barrel nuts. Heat guns and propane torches may work but take to long. Use an acetylene torch with a heating tip (go lightly).



The Savage Model 99 is a lever action hammerless rifle fed by an internal rotary magazine. It was produced from 1899 until 1998.

gunsmithing note(s):

      • READ THIS COMPLETELY THROUGH BEFORE PERFORMING ANY ACTION: To tighten or loosen the tension on the rotary magazine (Carrier) place, DO NOT TURN, a notched screwdriver (the notch needs to be wide enough to span the end of the threaded end of the Carrier Spindle while still slotted in the Carrier Spindle Nut) on the Carrier Spindle Nut (to find the Carrier Spindle Nut remove the forend you will see a slotted nut on the threaded end of the Carrier Spindle.). While holding the notched screwdriver on the Carrier Spindle Nut still and holding the Carrier (the rotary magazine fins) from rotating, remove the Carrier Spindle Head Screw (the screw above and just forward of the round count window on the left side of the action). When you remove the Carrier Spindle Head Screw the tension of the rotary magazine will stop being held by the Carrier Spindle Head Screw and transfer to the notched screwdriver on the Carrier Spindle Nut). Turn the Carrier Spindle Nut (clockwise (while looking at it) to reduce the tension and counterclockwise (while looking at it) to increase the tension) while holding the Carrier (the rotary magazine fins) from rotating, and trying to put the Carrier Spindle Head Screw back in. Go slowly and feel for the slot the Carrier Spindle Head Screw fits into. When you find the slot for the Carrier Spindle Head Screw slide it in and tighten. Release everything and remove the screwdriver from the Carrier Spindle Nut, Check the tension on the Carrier (the rotary magazine fins). If it feels right, test the action with dummy rounds or test fire at the range. If it passes, then you are complete. If not repeat the above until it does. Things to think about: 1.) The gun may fail to feed because the carrier tension is too high or too low; experience should point you in the correct direction. 2.) Having an assistant (with two extra hands) to help you will make it easier to accomplish the simultaneous tasks described above. Before starting, make sure that both of you have read and understand what needs to happen when.

Henry Lever Action Rifles

The Henry Repeating Arms Company makes a series of lever action rifles in various calibers.

gunsmithing note(s):

      • When disassembling/assembling, the magazine tube hanger (near the muzzle) should be drifted by a non-marring punch that has been shaped to fit in the dip below the dovetail and the start of the ring. This is the only way I have found to do this that does not crack or break the edges of the dovetail on the hanger.


Colt uses an ‘&’ as an action mark to indicate that a revolver had been returned for factory repair or refinishing.


  • There is an image of an example ⇒ (scroll down to see marking) in Hallowell & Co.’s Illustrated Firearms Dictionary.


Footnotes / Sources:

Hallowell, Morris L. “Illustrated Firearms Dictionary.” Hallowell & Co., Inc., ⇒.

Mark 4 (Leupold)

The Leupold Mark 4 scope … .

gunsmithing notes:

      • The screws for the Remington 700 SA-20 MOA one piece rail for the Mark 4 are tightened to 22 in/lb (6-48) or 28 in/lb (8-40).
      • The screws for the Mark 4 rings are tightened  to 28 in/lb. Tighten screws opposite each other in sequence (catty corner).



Footnotes / Sources:

Direction sheet that came with product.

Random Knowledge: Marlin 336 Firing Pins

Marlin 336 rifles have two part firing pins. The two parts are the firing pin, front and firing pin. rear. There is an old style and a new style firing pin, front. The dividing line for which style firing pin, front a gun takes is the year of manufacture. Guns manufactured in 1984 and after take the new style firing pin, front. Those made in 1983 and before take the old style firing pin, front.


Footnotes / Sources:

Marlin Firearms Customer Service Department. “Customer Service Call.” Telephone interview. 17 June 2016.

DIY Gunsmithing Workshop: AR Platform Maintenance

Our gunsmith and graduate of the Pennsylvania Gunsmith School’s Master Gunsmithing Program, Patrick Heraghty, will be teaching a Do It Yourself Gunsmithing Workshop on the AR Platform Maintenance on Saturday, 2 Apr 2015 from noon to four PM at the Rivanna Rifle & Pistol Club (RRPC) main clubhouse.

The cost is $10 per attendee. Any proceeds that are not used for the workshop will go towards the maintenance of RRPC firearms and / or the RRPC youth program.

Attendees are required to have an AR for the hands on portion of the course.

The DIY Gunsmithing Workshops are geared towards giving attendees who have a basic set of tools the skills they need to work on their own guns.

If you are a member of RRPC, please contact Patrick Heraghty at 434-989-1263, or by stopping by the shop if you, or your guest, would like to sign up, have questions, etc.

Attendees are admitted to the course on a first come first served basis.