Interesting findings of Walther LP53 and Lucznik

[clarky]

Had these 2 apart yesterday, mainly to see if this new Konceptus tuning kit for the Lucznik will fit the Walther.
It will not but I noted that the Lucznik has a greater volume/stroke owing to a shorter piston. However, its of interest that the 2 guns produce similar power when in good order. The std Lucznik produced 380 fps and the Walther 375 fps with Hobby pellets. Both guns with new piston heads and good springs.
The reason appears to be that any slight differences in volume/stroke makes little difference at this size which should provide useful information to anyone planning to modify their guns strokes or piston lengths.
However, there does appear huge benefit to this kit which relies on using one spring.
The key here is not stroke/volume but one powerful spring equal to the usual 2 fitted but then allowing the use of correct guide rodding instead of the inner spring as guide rod. The inner spring as a guide is a bad idea really, producing vibration and lots of friction points as the coils pass over each other. The kit which uses delrin guide rods and a piston weight pushes the Lucznik upto 470 fps with no twang but the maker claims upto 500fps with some pellets.
Im now trying to work out how to fit such a kit to the Walther. Ill get back to you if I do any good.

[mrto]

As a person that has a couple of LP53's I did find that interesting.

Thanks for the post,

ATB.

[clarky]

As a person that has a couple of LP53's I did find that interesting.

Thanks for the post,

ATB.

Thanks buddy. I am not expecting much interest because I think most owners of LP53s inparticularly, will want to keep their guns as design and I don't blame them. For me however, this kit does not permanently alter design but does improve the gun a goodly amount.
The problem with the Walther is it uses a different piston head arrangement. While a whole raft of piston heads can be spun up and fitted to the screw on piston face (as with so many designs) of the Lucznik, the Walther has a one off method of fitting with a keyhole head unit comprising of a leather piston washer and steel keyhole/guide locator. Its a nice idea and dispenses with the need for screws but does cause real problems if wanting to fit your homemade Teflon/leather washer.
I will look at perhaps using this P18 Konceptus mainspring. It fits the piston of the Walther perfectly, then may turn up a guide rod to slip over the existing guide off the base of the grip cap.
The Walthers upper keyhole locater/tiny guide rod at the other end rules out the piston weight fitting in the kit which gave the Lucznik 25fps during my tests. A good 50 fps came from the spring and guide though, meaning one should be able to get the Walther to within 25fps of the Lucznik.

[mrto]

Thanks buddy. I am not expecting much interest because I think most owners of LP53s inparticularly, will want to keep their guns as design and I don't blame them. For me however, this kit does not permanently alter design but does improve the gun a goodly amount.
The problem with the Walther is it uses a different piston head arrangement. While a whole raft of piston heads can be spun up and fitted to the screw on piston face (as with so many designs) of the Lucznik, the Walther has a one off method of fitting with a keyhole head unit comprising of a leather piston washer and steel keyhole/guide locator. Its a nice idea and dispenses with the need for screws but does cause real problems if wanting to fit your homemade Teflon/leather washer.
I will look at perhaps using this P18 Konceptus mainspring. It fits the piston of the Walther perfectly, then may turn up a guide rod to slip over the existing guide off the base of the grip cap.
The Walthers upper keyhole locater/tiny guide rod at the other end rules out the piston weight fitting in the kit which gave the Lucznik 25fps during my tests. A good 50 fps came from the spring and guide though, meaning one should be able to get the Walther to within 25fps of the Lucznik.

Even more interesting, because as much as I like the LP53 it is a bit gutless power-wise and if the power can be upped smoothly and any mod reversable I am all ears.

If only there was a way of getting the LP3 to perform a bit better eh?!

[clarky]

Even more interesting, because as much as I like the LP53 it is a bit gutless power-wise and if the power can be upped smoothly and any mod reversable I am all ears.

If only there was a way of getting the LP3 to perform a bit better eh?!

Ok ive homed in on why the Walther is just as powerful as the stock Lucznik despite a smaller volume.
Its because the piston is heavier. Due to the strength of the mainsprings the walther is better balanced in piston weight terms because its longer in length, despite losing a good couple of mm in stroke length due to the keyhole paraphernalia.
This why the Konceptous kit contains a piston weight of considerable (relatively) size....these little pistons lack weight!!
I have drawn up a design for a Delrin guide rod which will slip over the Walthers existing guide, complete with lower top hat of approx. 1mm ...or the same as a conventional guide in shape (im not sure how thick I can go with this yet) The guide will now be a nice slide fit on the outer spring, not the inner. This should now accept the P18 lucznik none stock spring.
However, the piston head end has a tiny guide (length of 8mm) which will now be loose on the outer spring and rendered useless of course but should not matter as the piston will do the job at that end just like any airgun with no top hat.
I will get here over the course of the B/hol and then maybe look at a piston weight washer if I get left with any room after assembly.
Im setting myself the challenge of 450fps but maybe being optimistic...

That LP3 you mention cannot be improved sadly. Even the new piston head replacements cannot drive them above 350fps.
We looked at setting the head closer to the valve but its near enough perfect. I would say less then 0.1mm of clearance to take up ....perhaps 10fps or something but risking the piston bottoming down and straining something.

[GRAZY]

I love the lp53 and have not yet had mine apart, I was always a bit put off that I may end up damaging the finish to the grip cap. I have seen this recommended to be done with a soft metal strap twisted tight around like an oil filter remover, but I've never been too sure on this. That aside I would love to improve the feel of the pistol as it always seemed a bit clunky when shot and not so much bang for your buck in the power stakes.

[clarky]

I love the lp53 and have not yet had mine apart, I was always a bit put off that I may end up damaging the finish to the grip cap. I have seen this recommended to be done with a soft metal strap twisted tight around like an oil filter remover, but I've never been too sure on this. That aside I would love to improve the feel of the pistol as it always seemed a bit clunky when shot and not so much bang for your buck in the power stakes.

No my friend its dead easy to remove. Just unscrew anti clockwise but with the palm of your left hand driving upward slightly as you unscrew in anticipation to receive the jolt as the cap comes free. Its not under spring compressor like forces but enough to fly down to your balls if your not careful.
At this point there is nothing to lose, no trigger springs to go flying off....just the 2 mainsprings that you can inspect and lightly grease. The cap and springs come out with about 10lbs of force under approx. 30mm of preload. You will easily cope with it but I would not recommend the operation for a junior.
Its getting the piston out where your problems start. So if your not a bit handy mechanically stop here.
When you put your grip cap back on you need to drive upward and turn at the same time. Put a tiny drop of lube on the threads to help if wanted but ive never manage to damage the finish any in many strip downs.
Its possibly the easiest gun to access the springs but the hardest with the piston. You need to get the cocking pawl out to do that, which requires the pin tapping out which sits under the grips so the grip panels need to come off first.
I can give you an instant 20fps with a thruster washer to sit under your springs, machined from self lubricating Delrin. but I have not moved into the world of Walther 53 tuning because the piston head is such a complex little bugger to allow easy mods.
I will post more regarding the performance of this P18 spring in the Walther and possible a Delrin guide rod but it requires careful planning, measuring and try out before I would report anything positive here.

[GunDad]

Being the owner of an LP53 already, I'm reading this with interest, although I don't intend any mods to mine. It comes out several times a year for light use, and always performs faultlessly. I've been tempted a few times to remove the end cap for a spring relube, but 'if it ain't broke, don't fix it' is always foremost in my mind.
In fact holding a FAC and fortunate enough in my location to have several S&W .22 lr revolvers & pistols, I can honestly say I get equal satisfaction whenever I bring out the Walther (for use at 10 meters), such is it's fine engineering, balance and excellent feel throughout the firing cycle. It's one of the few air pistols that I've been tempted to duplicate.

[clarky]

Being the owner of an LP53 already, I'm reading this with interest, although I don't intend any mods to mine. It comes out several times a year for light use, and always performs faultlessly. I've been tempted a few times to remove the end cap for a spring relube, but 'if it ain't broke, don't fix it' is always foremost in my mind.
In fact holding a FAC and fortunate enough in my location to have several S&W .22 lr revolvers & pistols, I can honestly say I get equal satisfaction whenever I bring out the Walther (for use at 10 meters), such is it's fine engineering, balance and excellent feel throughout the firing cycle. It's one of the few air pistols that I've been tempted to duplicate.

Its a good little shooter but major flawed (in comparison with modern springer design) for utilising 2 mainsprings one inside the other in attempt to pull out the most from its small internals. Basically the large outer spring is guided by the inner as a sudo guide rod but guide rods should be ultra smooth and not trying to twist or rippled with bound up coils. Hence the firing cycle is one of thud, twang bounce, when it only needs to be a thud.
I did achieve what I was seeking at the start of the post but did not relay anymore of my findings due to lack of interest in the thread.
I will however launch a topic on the airgun forum for anyone who is interested.

To be fair this site is more about springer tuning and PCP stuff, where pistols are a tiny side topic.

[eyebull]

Its a good little shooter but major flawed (in comparison with modern springer design) for utilising 2 mainsprings one inside the other in attempt to pull out the most from its small internals. Basically the large outer spring is guided by the inner as a sudo guide rod but guide rods should be ultra smooth and not trying to twist or rippled with bound up coils. Hence the firing cycle is one of thud, twang bounce, when it only needs to be a thud.
I did achieve what I was seeking at the start of the post but did not relay anymore of my findings due to lack of interest in the thread.
I will however launch a topic on the airgun forum for anyone who is interested.

To be fair this site is more about springer tuning and PCP stuff, where pistols are a tiny side topic.

I'm sure there would be some interest on the UBC.
I am very tempted to buy a predom now I have seen this thread and I know it can be made to shoot better. My LP53 is too nice to use all the time...one of the few airguns I am precious about

[deerwarden]

I.m really interested as I have always wanted one and now have one, I have a hobby lathe and will be interested in making delrin guide etc and doing the spring mod if it gets a bit more FPS and smoother action. deerwarden

[Josie & John]

Hi Clarky,

I would be interested in your findings. Bearing in mind the difficulties with piston access, would a 'half' tune consisting of a replacement mainspring and delrin guide be an easier option for those like me, who are mechanically challenged? It ought to smooth things up, if nothing else with the advantage of being instantly reversible.

Excellent thread and sensible advise -well done.

John

[clarky]

Hi Clarky,

I would be interested in your findings. Bearing in mind the difficulties with piston access, would a 'half' tune consisting of a replacement mainspring and delrin guide be an easier option for those like me, who are mechanically challenged? It ought to smooth things up, if nothing else with the advantage of being instantly reversible.

Excellent thread and sensible advise -well done.

John

Actually yes, indeed that's all I was able to do with the 53.
The first problem I had to consider is the initial performance. The Predom will edge the 53 from stock (if running as it should) but not by much.
Which puzzled me because it should be considerably better.
The reason for this is advantage's and disadvantages equalling each other out. The Predoms piston is much shorter, allowing more volume and stroke for more power potential but then hampered by being quite a bit lighter than the 53s. Given these guns have pistons which are far too light for the mainspring power, it virtually kills all the advantage of that extra volume/stroke.
Adding weight to the Predoms piston in the form a top hat brings about a big 35fps increase therefore.
In other words, if we can get both pistons weighing almost the same, the shorter length and greater stroke of the Predoms piston can then have the effect you would imagine.
Im going to shock you but with as much weight I could add and the P18 spring working on a Delrin guide rod saw the Predom almost manage 500fps with regular light match pellets.
This is why Konceptus have used the guide rod and piston weight down inside the piston....in the hope of getting the most weight in possible.

Now onto the 53. Here we cannot pack much inside due to the keyhole guide rod arrangement of the piston head unit but at least it does offer us some weight in an "as design" no need to modify component. With not too much gain to be had here, I decided to leave stock and simply add a steel slip ring washer of 2mm thick, which ended up being the weight of about a £1 coin.
The little short guide rod of the head unit also prevents adding the guide rod or piston weights at this end of course. So I simply installed the P18 spring but machined up a delrin guide to slip over the existing guide fixed at the grip cap end. You must do this of course because without the inner spring, the single large diameter P18 spring will rattle around on the 8mm diameter guide. The wall thickness of the guide isn't great but should be robust enough as there is no twisting force or leverage.
The result is very good. It means that the 53 is even better from the guide rod point of view, with the guide at the correct end and the piston guiding the front of the spring as is normal with tuned air rifles.
Results revealed that the 53 got the 450fps I was hoping for (low of 438fps to 456fps high) but easily the smoothest of the 2 guns.
Before anyone asks, this p18 spring of thicker Swedish wire does not allow the fitting of the std inner mainspring in an attempt to get even more power but it is virtually as powerful as the the 2 std springs together but the real bonus is that you can then correctly guide rod it so that all its potential is released smoothly.

Deeper tests have revealed the P18 with correct low friction guiding gives us 35 fps in both guns (roughly from std set up with duel springs)
The extra weight of the 2mm slip washer in the 53 (all I could get in without modification to the head unit) gave 9 fps
The extra weight of the big piston weight in the Predom gave 30fps
The extra stroke of the short Predom piston (once correctly weighted) gave 25fps

[Josie & John]

Thanks for the update Clarky,

Does your modification entail extra cocking effort and potential wear to the cocking lever/linkage? Also, with the increase in power, does the rearsight run out of adjustment at close distances of 6 yds or so?

It certainly sounds impressive.

Kind regards,

John

[clarky]

Thanks for the update Clarky,

Does your modification entail extra cocking effort and potential wear to the cocking lever/linkage? Also, with the increase in power, does the rearsight run out of adjustment at close distances of 6 yds or so?

It certainly sounds impressive.

Kind regards,

John

No cocking increase, or strain increase as the single mainspring has about the same strength of compression as the 2 stock springs, indeed perhaps very slightly less. However, all that power is released much more smoothly and with much improved efficiency meaning velocity does increase.
The 50fps to 100fps (gun dependant) did required 3 clicks down on the 53 elevation but did not run out of adjustment on either gun.
The gun seems to go off with a sharp fast thock, without the boing and twang when using 2 mainsprings