Lightening GP100 hammers

[RsqVet]

Anyone lighten their GP100 Hammer by drilling?

Recent discussions here on the hammer mass vs. hammer speed subject got me to thinking as I was cleaning one of my GP's why not drill the hammer out much the same way that aircraft components are lightened. I am not one for bobing hammers as I like to shoot single action, or preserve that option.

The GP hammer looks like it could loose a fair bit of mass in non-critical areas, and perhaps result in the same reliability with a lighter mainspring? Might just try this, worth a little risk for the fun of experimenting.

What do you all think?

[Redhawk5.5+P+]

That on paper it sounds prettty cool, I totally understand the concept.

Unless the gun is expendable, leave well enough alone.

TBS, this is coming from a hack.

Next question!

[MrBorland]

To increase hammer speed, the real goal is to reduce the hammer's Moment of Inertia, so where mass is removed is important. The farther from the pivot point, the better, so it's easiest to just bob the hammer. For those wanting to keep SA capacity, though, the hammer can be skeletonized. Here's a link with some good info:

http://rugerforum.net/gunsmithing/99...ification.html

[EdInk]

I was thinking a skeletonized hammer like a lot of 1911s. Try it out. The worst thing that can happen is you have to buy a new hammer.

[MrBorland]

Originally Posted by EdInk

The worst thing that can happen is you have to buy a new hammer.

Yeah, well, therein lies the rub - AFAIK, Ruger won't sell you a replacement hammer. You might get lucky and find one on GunBroker or Numrich, but otherwise, you'll likey have to send the gun back to Ruger if you botch the job. On your dime, of course. And if you've modified the gun, they'll return it to stock configuration before sending it back.

[Don P]

I bobbed me hammer on my GP-100 and no issues with reliability. Spring pressure is what will make it go bang not hammer mass. If the latter was the case then how do all those semi-autos with skeletonized hammers shoot without issue??? Take a look at the hammers that are available for the S&W 686. Virtually half or better of the hammer has been machined away and they function like a raped ape.

[MrBorland]

Originally Posted by Don P

Spring pressure is what will make it go bang not hammer mass.

We're getting a little OT, but to clarify, spring tension per se isn't what ignites primers, either. The spring stores the energy that the hammer delivers. Put in a heavier or lighter hammer, and delivered energy is the same.

Power is what ignites primers, and power is that energy per unit time. Though it's lighter and has less momentum, the lighter hammer travels faster, so delivers a more powerful strike. For instance, compared to a sledge hammer being swung, a car rolling at 1mph has 10 times the momentum, but the same energy. Yet the the sledge will deliver 10 times the power of the car, which is why it'll certainly affect your bumper more.

One advantage of a lighter hammer, then, is that you can run lighter springs while still delivering enough power to ignite primers reliably. Another advantage is the reduced momentum jars the muzzle less upon hammer strike. Combined with a shorter lock time, you can actually get an accuracy bonus by cutting that hammer down.

[Kreyzhorse]

Just curious why you want to lighten the hammer? Is it purely for aesthetic reasons or to make the gun weigh less?

[GP100man]

To decrease lock time.

[MrBorland]

Originally Posted by GP100man

To decrease lock time.

If springs are kept stock, yep, you can decrease lock time. But, as mentioned in my earlier post, a lighter hammer also allows one to run lighter springs without increasing lock time or decreasing reliability. How much lighter depends on a number of variables - how much mass was removed, where it was removed, smoothness of the action, etc.

A 3rd advantage is that a lighter hammer delivers a more powerful strike, but does so with less momentum - that's good because it's power ignites primers, but momentum that jars the muzzle. Below is a demo of this very effect with my 686 with a radically bobbed hammer (BTW, this revo has a 7.5lb DA and lights off everything I feed it):

http://www.youtube.com/watch?v=lmy5m...hannel&list=UL

[GP100man]

For every action there`s an equal reaction.

The action of the hammer fallin is what jars the revolver.

Kinetic energy built up in that motion delivered thru the transfer bar & firing pin is what pops the primer.

[jct61765]

Keep in mind hammers are casehardened. Usually only about .060 of a hammer is hardened on the outside. The inside is relitivly soft. This makes it more durable. Grinding off the spur wont weaken it. Grinding on it in key stress areas will weaken it. It will eventually break.

[dahermit]

Conventional wisdom is that hammers are case hardened (soft inside, extremely hard, thin exterior). However, some brands may be high-carbon, hardened and drawn (tempered) so that they are harder (and tougher) all the way through. I do not know for sure. Nevertheless, they will not be easy to just drill through to produce holes for lightening purposes. In either case, drilling such metal is a problem.
A side note: Most of the people (but not all), who respond to questions like this have no credentials relative to what they are posting, they are just repeating what they have been told or read, that may not be true (Example: "You cannot weld Cast Iron.").

[drail]

If you are going to drill holes in hardened tool steel then you better buy some good (expensive) bits and run them at the correct speed. One more good reason to simply bob it with a cutoff wheel. I have bobbed a bunch of revolvers and never had one fail to set off a primer. Unless someone installs a wimpy cut down mainspring bobbing the hammer will have no effect on reliability. Plus faster locktime and no snagging. All of my competition and carry revolvers have the hammers bobbed right down to the frame when the hammer is forward. Avoid CCI/Speer primers if you do this though. Those things are stupid hard. Federal makes the best primers anyway.

[Slopemeno]

Ruger hammers are uniformly hard throughout.