Interesting findings of Walther LP53 and Lucznik

[Gerard]

Well I just had another little go with my LP53 and it seems I've confirmed your findings. My added piston weights come to exactly 18 grams and shoots 7.56gr H&N Finale Match wadcutters at an average of 465fps. Adding 2 grams, just barely possible with the space available, dropped velocity to 435fps. Removing all the weight drops velocity to 370fps or so. Going up to 16 grams brings it up to 445fps. Adding a 1mm shim under the spring guide (even 1.2mm hits coil bind before the sear clicks into place) drops velocity to around 455, but becomes erratic, jumping between high 430's and low 460's. So 18 grams added weight and 'just right' preload (about 6mm) from the base of the spring guide are just right for power.

[clarky]

Well I just had another little go with my LP53 and it seems I've confirmed your findings. My added piston weights come to exactly 18 grams and shoots 7.56gr H&N Finale Match wadcutters at an average of 465fps. Adding 2 grams, just barely possible with the space available, dropped velocity to 435fps. Removing all the weight drops velocity to 370fps or so. Going up to 16 grams brings it up to 445fps. Adding a 1mm shim under the spring guide (even 1.2mm hits coil bind before the sear clicks into place) drops velocity to around 455, but becomes erratic, jumping between high 430's and low 460's. So 18 grams added weight and 'just right' preload (about 6mm) from the base of the spring guide are just right for power.

Wonderful work Gerard and very happy your own work mirrors my findings.
In microcosom this is likely how it is for all springers....Climbing in performance until a margin is crossed.
My findings also concluded that anymore weight would only increase the jump of the gun but i found the first 15 grams had virtually killed secondary recoil and improved the accuracy over stock.
The 25 gram spring guide started to return some slight extra slam ...suggesting i had messed up the balance before i even tried it over the chrony.
Its just so easy making such adjustments with this gun due to the ease of access.....possibly the easiest gun ever to access the mainspring and guide at any rate.

The difference in velocity we are getting likely to be pellet choice or piston head condition but seems your within about 25 fps or so of mine.
Great work

[Gerard]

Yeah, I just happen to have a supply of the 7.56gr pellets on hand. If all i had were 7gr 'pistol' pellets my tuning adventure would likely turn out just a little differently in terms of springer strength/length and piston weighting. Access certainly is easy! At least it has become so, since epoxying on a larger collar over the mutilated original cap, and the gradual reshaping of the threads to truly round by simply turning the cap off and on a bunch of times with greased threads. It was like an irregular octagon when I bought it, seriously... vise-grips... why, people, just why? But all working smoothly now.

[clarky]

Yeah, I just happen to have a supply of the 7.56gr pellets on hand. If all i had were 7gr 'pistol' pellets my tuning adventure would likely turn out just a little differently in terms of springer strength/length and piston weighting. Access certainly is easy! At least it has become so, since epoxying on a larger collar over the mutilated original cap, and the gradual reshaping of the threads to truly round by simply turning the cap off and on a bunch of times with greased threads. It was like an irregular octagon when I bought it, seriously... vise-grips... why, people, just why? But all working smoothly now.

im certain ive seen one of those grip cap/ guide rod units going spare on a site somewhere

[Gerard]

No need on my account. I'm happy with it, and will spray it with epoxy paint and low temperature bake it sometime when I've got a couple of other things needing the toaster oven treatment. Might first use a diamond burr on the Dremel to add knurling, but not decided yet.

[Leonardj]

Clarky - tried to send you a PM, but got this message:

clarky has exceeded their stored private messages quota and cannot accept further messages until they clear some space.

How about posting some pics of the LP53K that you built?

[clarky]

Clarky - tried to send you a PM, but got this message:


How about posting some pics of the LP53K that you built?

ok buddy i have deleted my cashe ....you should now be able to send PM
Send me an email ill post you some .....i do not seem to be allowed to add pics....maybe if i send to you you could add some here .