Hammerli 103 free pistol trigger adjustment

If you wish to make a donation to this forum's operation , it would be greatly appreciated.
https://www.paypal.com/paypalme/targettalk?yours=true

Moderators: pilkguns, m1963, David Levene, Spencer, Richard H

Forum rules
If you wish to make a donation to this forum's operation , it would be greatly appreciated.
https://www.paypal.com/paypalme/targettalk?yours=true
Post Reply
PaulB
Posts: 597
Joined: Tue Mar 09, 2004 9:18 am
Location: Charlottesville, VA
Contact:

Hammerli 103 free pistol trigger adjustment

Post by PaulB »

Anyone know how to adjust the trigger weight on a Hammerli 103? The trigger sear adjustment is the only external screw that one can see (right behind the trigger) and the 10P files on this site tell you how to adjust it. The pictures on the 10P page show the trigger weight adjustment screw being right next to the sear adjustment screw but there is no such screw on my pistol. When I take the grips off I can find no adjustment screws under the grips except one large screw on the front of the lower part of the cocking lever, that in the case of my pistol will not turn at all in either direction, and it is not obvious what it does anyway.
User avatar
6string
Posts: 445
Joined: Tue Aug 14, 2007 11:53 pm

Re: Hammerli 103 free pistol trigger adjustment

Post by 6string »

Hi Paul,

I saw your post earlier, but lost track of time. As you mention, the single screw on the 103, and earlier Hammerli free pistols, basically sets the engagement of the trigger with the first lever of the five lever set trigger mechanism. It does have a slight bearing on pull weight, but only to the degree of +/- a few grams.
Trigger weight is more generally regulated by the leaf spring that bears on the trigger itself. The spring can be adjusted or replaced by a gunsmith. On later Hammerli models, a second screw was added. This screw adjusts the tension that the trigger return spring bears on the trigger, thus regulating pull weight.
It is possible to have that second screw added to the earlier trigger type. This allows the average user to regulate pull weight.

But, in any discussion of the Hammerli set trigger, it is very important to be aware of the need for proper cleaning and lubrication of the trigger mechanism. Many people have gotten themselves into trouble dealing with the Hammerli by not understanding the precision with which it was built. We have all heard the comparison "built like a Swiss watch". This is an appropriate comparison. Like a fine watch, regular maintenance is the best policy. Cleaning and lubrication can be carried out without fully disassembling the mechanism so long as it is done on a regular basis. In fact, I would discourage disassembly. Firearms grade lubricants are not a good choice. The set trigger mechanism is lubricated very judiciously with thin viscosity watch oil only on the correct contact points. Swiss watch oil comes in many types and viscosities. Each has its place. For example, extra thin viscosity is good if you shoot in colder weather, but may be too runny in hot weather. The old oil may need to be cleaned off first. There are also natural and synthetic oils. Traditionally, the former has some natural oil ingredients including neatsfoot. Thus, the shelf life is rather short, maybe a year or two in the bottle. If your Hammerli has been sitting around unused for a while, it is very possible that it has gummed up. In extreme cases, this is where the service of a gunsmith comes in! There is an old joke that watchmakers like the natural oils best because it keeps a customer returning for service every couple years! And, of course, most watches don't get full of powder residue either. So, that's another point: only use good quality ammo!

Sorry for not replying earlier. The Hammerli is a very special grade of gun. I hope you enjoy and treasure it!

Best regards,
Jim
Post Reply