Hammer riding on barrel
I would be interested in a hammer that rode the barrel as a guide as opposed to using the frame as a guide. If your familiar with Leupys hammers, something along those lines. His website is here if your not familiar.
http://www.leupyscustomshop.co.uk/content/gallery.php?twg_album=hammers
–quote from his site– “Unlike the standard frame guided hammers provided by Gunpower, which rattle down the frame on their way to collide at varying angles with the breech slide, most of my hammers are barrel guided, which means they never touch the frame. This design gives precise alignment and presentation at the breech, controled to very fine limits by the barrel clearance, cleaner and more consistent trigger sear release, and is quieter in use because the hammer doesn’t rattle against the frame. These hammers glide completely unlubricated on the polished barrel, giving a very consistent hammer strike, and as an added bonus, have a much improved, superlative cocking feel.
Interesting idea, I’d be interested if ya made some.
BTW, your micropolisher needs a good kick in the arse!!
Be good to ask Leupy first.
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In the stock hammer even though its a larger diameter its only 2 small sections in contact. In your design its the entire barrel in contact so I’d say there’s going to be more friction.
Your saying it will be close tolerance in your design in your reply to riffraff.. but then you give it as a negative in the stock hammer – which it isnt a close tolerance design anyway….
The linear and radial stuff is nonsense – The gross movement is the same one tube is moving within another, which one moves relative to the shooter doesn’t matter at all – same type of movement.
Your also comparing a stock mass produced part with a custom made one – it will be smoother simply because its better made
I dunno. All I do know is chatter with the stock setup is a common issue and a sleeve moving over a rod is smoother. I don’t understand the physics of why but I do have an intuitive sense of it being so. Maybe an off-centre spring exerts more force to one side of a frame-bearing hammer, and because the total load-bearing action is so radially wide (1″) it allows it to jam and unjam at high speed, creating ‘chatter’, whereas a hammer bearing on the barrel is less subject to such interfering forces. Greater width = greater leverage perhaps.
That would make a very whippy barrel, and any less and you will still have the same effect I described earlier.
Unless of course you use a much larger breech ID.
only as much as is required to allow a hammer glide the same size as the breech glide.
it was late and i figgered folks would get the meaning
In the stock hammer even though its a larger diameter its only 2 small sections in contact. In your design its the entire barrel in contact so I’d say there’s going to be more friction.
Your saying it will be close tolerance in your design in your reply to riffraff.. but then you give it as a negative in the stock hammer – which it isnt a close tolerance design anyway….
The linear and radial stuff is nonsense – The gross movement is the same one tube is moving within another, which one moves relative to the shooter doesn’t matter at all – same type of movement.
Your also comparing a stock mass produced part with a custom made one – it will be smoother simply because its better made
I’d say it might be true if it were metal on metal with a sharp edge – but each end of the standard hammer has a delrin bushing with radiused edges. Bouncing around on its travel if grossly undersized yes – but no chatter.
My hammer doesn’t have two points of contact on the barrel, it’s a single continuous contact-patch and friction is unable to develop, due also to the very limited radii involved.
With the frame-bearing method the radii are significantly bigger. Yes, the contact-points are delrin, but the friction isn’t caused by gradual drag, it’s caused by high-speed high-frequency impacts. Yes, you can eliminate those almost entirely by ensuring a very tight tolerance, but then you will get drag-induced friction, simply by virtue of the very large radii involved. You’ve got two 1″ circles binding down an anodised tube. You’ve got the bearing-load being distributed outwards onto a circumferencially large surface instead of inwards onto a circumferencially small surface. The load-surface is hugely more well distributed with the barrel-bearing method than with the frame-bearing method (ie, it’s smaller AND linear instead of bigger AND radial).
Maybe if you think of it slightly differently and imagine a shaft going down into the ground. Two methods of dropping a tube down it, one where the tube has a raised edge at both ends that bear on the wall of the shaft, and the other where the tube rides down a pole in the centre of the shaft. If the wall-bearing tube gets slightly out of whack as it drops it’ll actually lock up and stop. That would not be able to happen with the tube riding down a pole. With the pole the tube becomes self-correcting, by virtue of how the forces are distributed.
So you agree that a 2 point of contact hammer riding on the barrel will have the same issue as a 2 point of contact bushing riding on the frame that you theorize.
I’d say it might be true if it were metal on metal with a sharp edge – but each end of the standard hammer has a delrin bushing with radiused edges. Bouncing around on its travel if grossly undersized yes – but no chatter.
I’d think any properly sized hammer would work just fine either way.
A frame-running hammer has two thin contact-points, quite far apart. This arrangement can induce ‘chatter’, where the two ends ‘bounce’ from their contact-point within the frame asymmetrically. That produces inconsistent speed and thus inconsistent air-release and ultimately FPS.
A barrel-running hammer cannot suffer the same problem and is hugely smoother and more consistent in operation. 🙂
I’d say thats more a design and tolerence problem with the original hammer – make a hammer thats barrel riding to a similar design and tolerence and you’ll have the same “issue” – if it even exists.
It can’t happen with a bearing-surface that’s of one piece, it takes two seperate surfaces to tango (as it were), each feeding off the other. The frame-running method also increases the span considerably, which exacerbates the issue with stability and leads to chatter.
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I’d think any properly sized hammer would work just fine either way.
A frame-running hammer has two thin contact-points, quite far apart. This arrangement can induce ‘chatter’, where the two ends ‘bounce’ from their contact-point within the frame asymmetrically. That produces inconsistent speed and thus inconsistent air-release and ultimately FPS.
A barrel-running hammer cannot suffer the same problem and is hugely smoother and more consistent in operation. 🙂
I’d say thats more a design and tolerence problem with the original hammer – make a hammer thats barrel riding to a similar design and tolerence and you’ll have the same “issue” – if it even exists.
Why is it so much better to have the hammer run on the barrel than on the frame exactly?
I’d think any properly sized hammer would work just fine either way.
I may be picturing this wrong, so correct me if I am please.
Anyway, if the hammer is smaller than the frame ID and is riding on the barrel, what is keeping it from tilting downward just before it impacts the breech?
The bearing surface would slide off the fat end of the barrel 1.5″ before it hit the breech. The smaller od of the hammer would allow it to tilt downward inside the frame, correct?
How much of a reduced OD of the hammer are we talking about?
Someone enlighten me. This sounds like a recipe for inconsistency.
There is enough hammer left on the fat bit of barrel, and tight enough on it, that it can’t droop.
The post office said they would deliver my express mail to you on friday the 3rd. I don.y see my name on that list, on page six.
Voltar, you mean you turn the barrel full length to the same diameter as the breech end?
That would make a very whippy barrel, and any less and you will still have the same effect I described earlier.
Unless of course you use a much larger breech ID.
I may be picturing this wrong, so correct me if I am please.
Anyway, if the hammer is smaller than the frame ID and is riding on the barrel, what is keeping it from tilting downward just before it impacts the breech?
The bearing surface would slide off the fat end of the barrel 1.5″ before it hit the breech. The smaller od of the hammer would allow it to tilt downward inside the frame, correct?
How much of a reduced OD of the hammer are we talking about?
Someone enlighten me. This sounds like a recipe for inconsistency.
the barrel is reduced in diameter full length
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I don’t know all the physics issues involved but I run a Leupy hammer and It’s spot on. If you mirror polish your barrel surely the hammer will be better running on that than the inside of the frame? Drum’s hybrid hammers are mostly plastic (PTFE, Nylon) I’m not 100% sure but they glide on my barrel effortlessly. They have a textured running surface too which is supposed to minimise running friction. It keeps my rifle running consistant even without the regulator fitted 😉