Today blog reader Ian McKee and I are at Day one of the SHOT Show. Tomorrow’s report will include Range day and Day one of the show.
In the blog today Ian, whose blog name is 45Bravo, tells us about his experience of repairing a Marksman BB pistol. This report is especially good because there are many Marksman pistols available and they make good dart guns.
If you’d like to write a guest post for this blog, please email me at email@example.com.
Take it away, Ian
Repairing a Marksman spring air pistol
by Ian McKee
Marksman BB air pistol.
This report covers:
- A tip
We know the Marksman repeater air pistol is not particularly well regarded as a pellet and BB gun, but it was also intended to shoot darts, and apparently it shoots them pretty well! Today we will look at repairing a Marksman Repeater air pistol so you can try out the dart gun scene with your vintage Marksman air pistol that may be in need of repair.
As far as I know, this guide will apply to all iterations of this pistol made from the 1950’s until the current production models available in 2023 including the Blanca pistols produced in India. As always, take photos during the disassembly process to help with putting all the bits and bobs back where they belong.
To start, you need to depress the thumb safety to unlock the slide, then pull the slide rearward until it is fully cocked, this will allow you access to a flat spring steel clip that is located under the rear of the slide as shown in the photo, You can remove this with needle nose pliers, hemostats, or a hooked o-ring tool.
Thumb safety down.
Pulling the slide all the way back cocks the pistol.
Remove this first. Just pull it straight up.
Once you have done that, you can pull the trigger to release the spring tension stored in this mainspring. The “slide” (the thing you pulled to cock the pistol) has tabs that fit into channels in the body of the gun, and you need to remove the slide by aligning the tabs with the cutouts as shown in the photo and spreading the sides of the slide until it clears the receiver.
These need to be lined up, and then spread the sides of the slide to let them clear the receiver.
On the right side of the gun are three screws, you need to remove these, they are all the same size so you don’t have to keep them in order. A thin screwdriver will allow you to separate the two halves, lifting the right side of the gun upwards.
These screws are all the same so you don’t have to keep track of their positions.
There are three springs in the gun, only the mainspring will want to shoot rearward as you open the pistol halves — so control it. The other two springs are located — one near the bottom of the tilting barrel, and the other one at the rear of the trigger arrangement.
These two are under tension, but normally do not have a habit of flying across the room. Pay special attention to the trigger spring, the lower leg wants to push the safety block upward, and the upper leg of the spring wants to move the trigger down and pivot it forward.
The correct orientation is shown in the photo, and the correct orientation of the barrel tensioning spring is shown in the next.
This is the correct orientation of the two torsion springs.
Trigger spring detail.
Barrel spring detail.
Since they are still under spring tension, I suggest removing these two springs first. Once these have been removed, you can remove the mainspring and captive inner spring assembly.
The early guns used a brass compression chamber, with a steel nozzle that is retained in the end of the compression chamber by a rubber insert. Later guns use a steel compression chamber and nozzle made as one piece. The rear of the compression chambers on some guns were rolled into a smaller diameter so the piston, compression chamber, and inner mainspring assembly was not easily user serviceable or repairable.
The new style compression chamber is much more robust than the older one.
Old style compression chamber
I’m repairing an early Marksman that is still marked Patent Pending and is in excellent physical condition. Internally, the nozzle had broken loose from its base and damaged the main seal on the piston as shown in the photo.
This main seal is definitely beyond repair.
I reached out to several of my sources for vintage airgun parts but Marksman seals were nowhere to be found. Of course that is compounded by the minor changes made to the design over the decades.
The only option was a donor gun. I had a later model Marksman that was made from plastic, but its compression chamber is made from steel, and that gun fires with good velocity.
In my opinion, the older metal one deserves to live more than the plastic one, so I had no compunctions in pulling the heart and lungs from the younger gun for the elder. “It’s not Frankenstein, It’s pronounced Fronkensteen” (that’s a quote from an old Mel Brooks movie titled, Young Frankenstein).
The donor part went in without any problems, and the elder Marksman is now alive and back in service with its owner.
I do want to cover a couple of reassembly points to help you if you are servicing and cleaning the internals of your Marksman.
I doubt this spring piston gun would benefit from a Tune in a Tube treatment, so I just used a small amount of moly grease on the two mainsprings, and the pivot points.
Install the tilting barrel arrangement in the closed position, then the safety and trigger and the long sear bar in position, making sure they are on their posts or in their recesses. Put the barrel spring back into place, but leave the long leg laying out between the receiver halves as you will use a small flat blade screwdriver to put the long spring leg in position as you are closing the halves.
Lay the mainspring and compression chamber in its place, and then put the trigger spring in position, paying close attention to its orientation, look at how when it is under tension it wants to move a part of the trigger on to the top of the safety, if this happens during assembly, the gun will seem to be locked up and you will have to take it apart and try again.
It helps to hold the trigger in place with a finger or a thumb through the trigger guard while putting the right side back on the pistol.
Other than putting the mainspring over the compression assembly the pistol is ready to close up.
To recap what has to be done all at the same time: the mainspring and compression assembly held in place under spring tension, the trigger held in place under spring tension, then the right half of the gun put into place (and still leaving the leg of the barrel spring hanging out for the moment.)
Once that is done, start the two screws on the grip and the top left rear of the frame, but do not tighten them. Then with a small thin blade screwdriver, you can lift the long leg of the barrel spring into the frame and over the post that holds it under tension, if you just put it inside the frame, and not over that post, the barrel will not have the proper tension to hold it firmly closed for firing.
Make sure you put the spring over this post.
Now add the third screw near the muzzle and tighten down all three.
Take the slide, and slightly spread the sides to put the raised guides into the notches that are in the rear of the frame, it is keyed and only goes in one way. Make sure it slides forward and back freely and stays in the track.
Using needle nosed pliers pull the steel rod that the spring clip attaches to rearward until the sear catches it and holds it in place. Move the slide into position, and attach the slide to the steel rod with the spring clip.
Push the slide forward and function test the gun.
If everything went right, your Marksman pistol is back in action and ready for a few rounds of darts with friends.
If you don’t have a Marksman, and wish to try the dart airgun scene on a budget, Pyramyd AIR sells the Umarex DX17, which appears to operate mechanically the same way as the Marksman repeater.
I have not yet had the opportunity to try the Umarex DX17 in person, nor have I disassembled one to see if they cross over to the Marksman in parts compatibility. But I have seen a disassembly video of it, and it seems to have the same mainspring arrangement I just don’t know if it is dimensionally the same.
Keep us posted as to how your Marksman is doing with darts, I am sure many readers would like to know.
Shoot safe, and HAVE FUN!