Tuning Belgian sold, French documented 1958 LP53 air pistol.

KroniK

Member
Jun 30, 2024
7
10
Hello everyone,

To start with, I'm going to need to admit I'm not an air pistol guy. I normally shoot the k98 and the related .22 trainers.
However, I saw this beautiful LP53 for sale and it instantly grabbed me.
These are the best kind of purchases, right?
It reminds me of a similar styled air pistol that my parents bought me on holiday in Italy in the '90s. Shooting rubber caps in the living room, I don't know if I would let my kids do that nowadays :)

I present to you a LP53 sold in Belgium, having French documentation.
I included pictures of all documents, for any collectors out there.
Also included was the reloading wooden handle, cleaning brush, all sight accessories and a bunch of ammo.
The serial number places it around May 1958.

It still shoots, but given the age, I don't know if anything needs replacement.
I'll see if they have a fps meter at my shooting range to determine the current performance.

So currently I'm trying to gather info to all my questions on how to do proper maintenance, greasing (I have neatsfoot oil for the leather seal), ...
Does anyone know if the cleaning rod is original? I don't find that exact shape in other examples online.
Also having a look into any spring upgrades. Already a big thanks to Steveoo for the wonderfully detailed posts.
I think I won't dare taking the piston out, unless the fps meter gives a really bad number and the leather seal needs replacement.
So I was looking into replacing the breach seal (I don't know if anyone can tell from the picture if it's necessary?) and the Protek power pack. I like that it's a reversable upgrade, so I doesn't detract from a collecting standpoint. However I keep reading from Steveoo that it's a butchered job, so I have mixed feelings about it.

I'm on holiday in London for a week later this month. So if I need to pick up anything that can't be shipped to Belgium, hopefully I'll have the answers by then.

Thanks for any insights

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I went to my gun range today to ask them about measuring the fps of the pistol.
The guy said that a conventional airsoft fps meter would be to inaccurate as it would have difficulty correctly registering the pellet.
That these are more tuned to picking up an airsoft bb as it offers higher contrast within the white noise.
So he suggested a measuring method where they will attach a device to the pistol that will register the vibrations of the shot going off, and then I assume a 2nd measurement of the target, giving them time and distance.

I want to believe the guy, but I wonder what your opinions are?
Is it more in the mindset of getting a very accurate result having competition shooting in mind?
Or are the 'airsoft' fps meters you find on Amazon (just to give an example) really not suitable for this?
 
I have one of the cheap Chinese chronographs that is sufficient for my purposes. I had to make a clear plastic shield to protect the led's after I managed to shoot one of them off... 🤦‍♂️


Luckily it was easy enough to locate a replacement and solder it on. They do read in m/s but it is easy to convert your results, just multiply by 3.28,

One way to get a VERY rough estimate of velocity is to shoot a flat-head pellet at a 'proper' match target, the sort made from the pale yellow card. If it punches a really clean, sharp hole you are probably around 450 fps or more, but if it is a slightly ragged hole, then you are 350 to 400 fps. A shapeless torn hole is going to be sub 300fps.

Hope this helps.
 
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The results came back, there's a nice surprise.
So firstly, the gun range did their test setup as described. They were surprised that the readings were so tight together.
They measured a consistent 115-117 m/s, so about 380 fps.
This was with the Diabolo basic 7.0gr pellets (the box behind the barrel in the picture I posted before).
These seemed to me the most standard pellets.


So that already made me very happy. Can't complain of a 5% loss compared to what I think the 400 fps it left the factory with in 1958.

So then the cheapest fps meter I could find from Aliexpress arrived. The same model as was suggested above. Cost: 21 euros (less than the half hour of work the gun range charged me).
What does it consistently measure? 115-118 m/s.
Now that really made my day.

Knowing all this, I'll leave the pistol as is. I'll only try to get some neatsfoot oil on the pistol seal.
 
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I heard of one method, but I have not tried it myself; you would need access to tools and a vice or large clamp.
Get a piece of softwood or mdf, about the thickness of the cap, it needs to be around 3 inches square. With a hole saw, cut a hole in the wood slightly larger than the cap diameter, then cut into the hole from one outside edge.
Maybe wrap some tape around the cap to make up any difference and to protect the ridges, insert the cap into the hole, then clamp it into the vice so that it will close up the saw cut and apply pressure more evenly around the cap.
You will probably have to play around with the saw cut width, or even cut another slot 180 degrees opposite so it becomes a two-piece clamp.
As I said, not tried this myself, but it sounds like a plausible idea.
Definitely apply a penetrating solution for some hours to give you the best chance of success.
 
Last edited:
I heard of one method, but I have not tried it myself; you would need access to tools and a vice or large clamp.
Get a piece of softwood or mdf, about the thickness of the cap, it needs to be around 3 inches square. With a hole saw, cut a hole in the wood slightly larger than the cap diameter, then cut into the hole from one outside edge.
Maybe wrap some tape around the cap to make up any difference and to protect the ridges, insert the cap into the hole, then clamp it into the vice so that it will close up the saw cut and apply pressure more evenly around the cap.
You will probably have to play around with the saw cut width, or even cut another slot 180 degrees opposite so it becomes a two-piece clamp.
As I said, not tried this myself, but it sounds like a plausible idea.
Definitely apply a penetrating solution for some hours to give you the best chance of success.
Some penetrating oil like Kroil for a few days, then something like above to clamp it. I used an old, thick leather strap to wrap around mine and a pair of waterpump pliers, worked good. I did replace the spring and piston seal. THose things are tricky to reassemble, it seems as though you need four tiny hands, but it can be done, Make sure you have some punches or small rods to use like drift pins.
 
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A last update from me.
I've given up, the pistol has won.
More than a week of daily spraying of a local Kroil alternative hasn't worked.
I tried the hole in a wooden board trick, but it couldn't find enough grip.

I'm leaving it as is, as I have a fine perfectly working pistol. I don't want to damage it.
I tried to lubricate the piston seal through the exit port with neatsfoot oil. Setting the pistol upright for a while. Manually pumping the piston.
My final fps readings stayed the same, around 380.

So the only thing I'm left with is an unused Protek upgrade kit in mainland Europe. If anyone is looking for one, message me.

Thanks again for all the help and suggestions.

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