1970's Weihrauch HW35

[hollandandholland1243]

I have an old Weihrauch HW35 from the 70's.  For some reason, it doesn't have a lot of power anymore and is no longer accurate.  The gun has never been worked on. I don't know much about the inner workings of this gun and was wondering if anybody had any ideas as to what the problem could be. Thanks.

[Yak54]

It's a good bet the old style seals are dried out and not doing their job.  More knowledgeable guys than I will probably know other possibilities. Stay tuned.

Dan

[hollandandholland1243]

Thanks for the information.  I'll look into the seals.

[bReTt]

It most likely has a leather piston seal and breech seal.  You can go synthetic or keep/remake a leather one.  I took mine down and the piston seal was still in usable shape but I replaced the breech seal with a new synthetic one.  I also replaced the mainspring.  If it's from the 70's like mine was (1978) it would do well with a new spring also.  I don't have the specs for the spring but you can compare to yours when you get it apart.  Seals and springs, those are expendable items and will need to be changed out eventually on every rifle.  If your has the leather seal and you want to convert to synthetic piston seal, you need to get a conversion kit to accept it.  You can find that at Vortek also.  Do your research to be sure to get the right parts needed for the job. 

http://vortekproducts.com/ourstore/index.php?route=product/category&path=45

http://www.airrifleheadquarters.com/page/page/251488.htm

[hollandandholland1243]

Thanks for the information.  I think it has the leather seal so that is probably the case.

[scrane]

Here's a link where you can get an idea of manufacture date and some of the production changes. Funny enough, I just got an HW35 from 1977 last week. Mine has a leather seal and I plan on keeping it that way. There are some threads around on having to modify the transfer port on leather sealed HW35s for optimum performance with the synthetic upgrade.
If you drop a couple of drops of silicone chamber oil down the transfer port you might get better performance out of your leather seal. If you take yours apart try soaking the seal with chamber oil if its not in bad shape.
During its heyday the 35 was thought of as a very powerful gun. Not any more.  10-10.5 fpe is about all you can expect from an older gun with smooth cycling. Accuracy should be good, though. Check your lockup, barrel pivot tension, and clean the barrel. Also check that the stock screws are tight.
Good luck and have fun.

http://www.airgunforum.co.uk/forums/showthread.php/131462-How-old-is-my-weihrauch