LP-400's air cylinder's threads wearing off

[amarinder]

My air pistol is 2 years old. My coach noticed that the cylinder's threads are wearing off. Similar problem has been noticed by 2 more shooters using this gun.

Somebody blamed the STEEL adapter for wearing down the threads. Anybody else facing the issue and solved it ?

[antispar]

Yes, it happened to two my club colleagues. Both pistols were repaired in Dortmund last year by Walther’s service team at no cost. What was funny is that the repairman had put a serious effort to explain to our coach how to fix the air cylinder on the pistol without damaging the threads!!!! Anyway, what we in the club have figured out is that the threads are too small i.e. the thread pitch is too small in the first place, which is coupled with narrow stub and too soft material (aluminium). Nothing of this is present on previous LP300s and therefore 15 to 12 year old pistols show none of the said problems, but Walther wants to keep it under the rag.

[pgmlml]

NO Steel at all! At least the magnet didn't stick....

and yes, i've compared the threads with the lp300 and the size/pitch is very different!

Every time I screw the cylinder I try to be as gentle as possible... on the other hand I know walther will fix it when it breaks :D

[amarinder]

Would it be a good idea if I apply grease on adapter while fixing the cylinder upon it for filling?

[pgmlml]

I would be a good ideia not to overscrew it!
I tried grease once, but had to clean it because it would get very dirt and i was afraid it would go inside the gun!

The question is, are people overscrewing bolts and cylinders?! As I said before, when I was a kid I used to overscrew everything... and I regret it as hell, because I broke so many things that I never had the oportunity to fix!!!

[Curlyjim]

antispar,
If it is the cylinder threads that are wearing, why did the pistols themselves need to be repaired? Were there any comments from Walther about the matter?

If it's just the cylinders, I wonder if maybe there was a batch of cylinders that weren't properly heat treated or something. Did Walther replace the cylinders?

I ask because I'm considering buying an LP400 and don't want to buy into a problem.

Curlyjim

[antispar]

Good point, it was not the pistol in question but the air cylinder (always one with Walther) and it was repaired. The problem is straightforward, threads with too narrow pitch are much more prone to misalignment and when that happens small/narrow threads gets quickly under too much stress, which is especially pronounced it they are made of soft material like aluminium is (that cannot be hardened by a heat treatment).
If Walther only made the thread bigger nothing of this would have happened. So, the problem is there to stay and the only way to avoid it is to be really gentle when attaching the air cylinder, taking good care to align the threads before the first twist. Otherwise, the pistol is nice, especially the trigger release feel and it shoots with barely noticeable upward flip (more than Steyr LP10, which is a benchmark).

[David M]

A little lube on the threads does wonders.
I use Festo air controls grease.
The threads will gall if left dry.

[Gwhite]

Walther probably stole the bad design from the Hammerli AP40 cylinders. The team I coach has several cylinders where the threads are nearly gone, and one aluminum fill adapter that has galled so badly it is useless.

The thing that works is to keep things clean, and use an anti-seize compound designed for aluminum:

http://www.amazon.com/Anti-Seize-Compou ... B00DAI26CO

[Andre]

I use white lithium grease on tank threads.

[Curlyjim]

Looks like something similar was discussed a couple of years ago on TT. There was at least one indication that the situation could be dangerous if the threads got too worn.

http://www.targettalk.org/viewtopic.php ... 17&start=0

curlyjim

[Gwhite]

When I saw some of the "threads" left on one AP40 cylinder, I was amazed it hadn't launched itself downrange.



One advantage of the anti-seize stick we use is that it is a waxy consistency, and won't attract dirt the way grease will.

[django]

Me xperience with grip bold damage. Low bold quality tear off and this metal crap attach on female treat. Take metal job to clean, make bigger female hole put bigger screw and sell it ASAP. After that Never buy walther gun anymore.

My friend on club xperience same thing ...cylinder threat wearing of. Not just wearing off but cracking on it hill treat. He went on local metal shop and they can repair.

[BEA]

Do not use a silicone based lube but rather use a petroleum based lube. Lithium grease is okay, high pressure bearing grease is better...the thick stuff you buy in a small tub.

[David Levene]

I was CRO on a 10m range today.

A shooter came on to the range saying that shed had a strange "bang" when taking her LP400 cylinder off the scuba tank after filling, and asking if she could just test it before the match.

I took her to an end firing point, the hall was virtually empty as we were still 20 minutes before "athletes to the line", and made sure the gun was pointing down range as she screwed the cylinder on.

It went on a couple of turns and then launched itself about 10ft down range.

Maybe not the best of designs ;-(

[Rover]

No hope if it's crap, but maybe a Teflon tape wrap for a while.

[David Levene]

No hope if it's crap, but maybe a Teflon tape wrap for a while.

The filling adaptor now goes in half way without turning it. No hope.

Guess which manufacturer is getting a cylinder back for repair.

[pgmlml]

I'm worried! what threads are worn ou, on the cylinder or on the pistol?! or both?!

[David Levene]

I'm worried! what threads are worn ou, on the cylinder or on the pistol?! or both?!

The cylinder.

[pgmlml]

I was going to say for you to use the 10 years voucher for the cylinder, but I think Walther should fix it for free! Porbably will take longer :(