Bobbing mim hammer in airweight

Larrymcc1

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I am bobbing a MIM hammer in an airweight for a friend which concern's me it may weaken the hammer. Additionally, I am concerned if it is too light, it may bounce causing misfires. All thought's appreciated.
 
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The factory cuts off the spur. There are a number of threads on this, but bobbing the hammer making it lighter does not affect reliability. The hammer goes faster, which more than makes up for its slightly less weight.
 
There's a new 'Wiley Clapp' edition J-frame on the market with a bob-job. Just keep as much 'meat' there w/o leaving any sort of hook which can snag.
 
I've seen many bobbed J frames; and I had my old Model 36's hammer bobbed. No problems after; but none were MIM. I agree with VictorLouis; keep as much "meat" as you can.
 
Bobbed hammer on 637-2. No misfires. For a while I even had a reduced power mainspring in, no misfires. Bob away, the gun will be fine.

bobbed+1.jpg
 
Reducing the mass of the hammer also increases the velocity. Energy=1/2mass x velocity^2. Practical experience bears this out, bobbing the hammer is every bit as reliable.
 
Reducing the mass of the hammer also increases the velocity. Energy=1/2mass x velocity^2. Practical experience bears this out, bobbing the hammer is every bit as reliable.

Actually I believe that it's
energy = mass x velocity squared (not 1/2 mass),
so increasing the velocity has much more effect than decreasing mass. Using this formula you'd have heavier primer strikes using the lighter hammer.
FWIW momentum is mass x velocity. Even using this formula, as mass goes down and velocity goes up, you'd keep about the same striking power.
 
Actually I believe that it's
energy = mass x velocity squared (not 1/2 mass),
so increasing the velocity has much more effect than decreasing mass. Using this formula you'd have heavier primer strikes using the lighter hammer.
FWIW momentum is mass x velocity. Even using this formula, as mass goes down and velocity goes up, you'd keep about the same striking power.

I love math, as long as it's not much more than arithmetic. ;) I like the certainty that these energy and momentum formulae seem to offer, but I have to wonder - is it certain that a decrease in hammer mass produces a directly proportional increase in hammer velocity? Such that we can draw a correct conclusion from these formulae that decreasing mass will not, mathematically, have an adverse effect on the firing pin's impact on the primer?

Or do things like spring dynamics (whatever the correct term is) in the hammer and firing pin springs, and perhaps inertia of the hammer and/or firing pin themselves (if the firing pin is frame mounted) come into play in ways that would change the results otherwise predicted by just the energy and momentum formulae?

Not trying to start a fight, just really curious about how these forces actually work. And I generally start with the assumption that, when talking about changing one part of a balanced mechanical system, usually "it's not that simple."
 
I believe in "empirical" proof. As in "I done it and it worked". Which I have. I own four bobbed-hammer Chief Specials and none of them has ever had a misfire. Good enough for me.
 
Here's a pic of my 360J's bobbed and polished MIM hammer. This gun has also been converted to DAO and has a very slick action, trigger pull about 8lb, zero ignition issues.

SDC10024.JPG
 
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