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Bark
01-31-2010, 01:01 AM
Very intresting indeed.Going solely on the feel and percieved impact on an A-Zoom,I would never have guessed abundant headroom on the strike.Also,locktime seemed a bit sluggish on the Savage,but I spend the majority of my triggertime on a Perrazi servicing a trap addiction.Having been involved for over 20 years in precision airguns(another addiction to be avoided) which are spring intensive,I've had many custom srpings wound at approx.$90 a pop local before I found these guys http://www.leespring.com/ Just measure length,mic the wire,and go up or down depending on need.Download the catalogue and off you go.Very easy people to work with.Sure do love these Savage rifles,acres and acres to play on. Old Grumpy Bark

sharpshooter
01-31-2010, 01:36 AM
First of all, cocking distance will never be equal to firing pin travel. By using a little common sense you should realize that. If you would actually physically measure it, you would see. How I gain firing pin travel is a trade secret. Like I said before, it took me 3 years to figure this out and I work on hundreds of actions a year. When you get that many under your belt, you'll have it figured out too.
I was never any good at algabra either, that's why I put the task to someone who is. Ottesons formula may be correct, but the numbers he uses are not. Like I said before the data he collected does not match what I have collected over 10 years and hundreds of actions. Garbage in-garbage out, if the numbers are not right, the end result is not right. Just be cause it's published and well respected, does not mean it's accurate.

Smokepole
01-31-2010, 10:35 AM
My common sense is failing me. Do tell. How can the firing pin possibly travel further than from the top detent to the bottom of the ramp (or the back of the bolt head)? It can surely travel less, if the primer is in the way, but I don't see how it can travel more. If you're worried about your trade secrets, get a patent.

As for Otteson's numbers, they seem to jive just fine w what RWO and I have measured on our individual actions. Measuring the spring rate is easy enough. Measuring compressed & relaxed lengths is easy enough. Allowing for sear friction/resistance is easy enough because it's almost negligible in relation to the amount of energy in the mainspring (which is one key omission Otteson makes and clearly states). The same can be said for friction elements between the firing pin and surrounding parts as well. I fail to see how Otteson, RWO, and I are so far off.

TheShootist1894
01-31-2010, 01:31 PM
Allowing for sear friction/resistance is easy enough because it's almost negligible in relation to the amount of energy in the mainspring (which is one key omission Otteson makes and clearly states).


Negligible? So if you have 6-8 lbs of sear resistance acting against a 25 lb spring you call a 33% loss negligible? I think not, granted a 10 lb spring will probably set off the primer sometimes, but will be inconsistent at best. . . .

Smokepole
01-31-2010, 01:45 PM
I doubt it's that much resistance, especially since I run a lightened or well worn sear spring. Take a look at that small torsion spring on the sear and compare it to the mainspring. See how much leverage the upper sear tab has on that torsion spring. Also, remember, that's a ramp on the sear. The cocking pin has LOTS of leverage on it. And what's more, that leverage increases as the sear drops out of the way (the ramp gets shallower). Most of the resistance will be purely frictional there. So yes, I call it negligible and include it in the safety factors between 75 oz-in and what actually is needed to pop an ideal LR primer. It's nowhere near 6-8lbs once the trigger breaks.

Another way of looking at this whole situation is as a closed system. At the end of the day, the input is a 90* throw w a force at the end of a lever arm, torque. That is an input energy that's converted to stored potential energy in the mainspring. That energy is then released to strike the primer. So, the only way to get a lighter throw is to decrease the energy of the primer strike or spread the input load out more evenly across the opening and closing of the bolt so you just don't 'feel' as much force. You're applying a smaller force over a longer distance. Same amount of energy in, but it doesn't feel like it. And there's a number of ways to accomplish that.

Can/will anyone here answer my question?:
"How can the firing pin possibly travel further than from the top detent to the bottom of the ramp (or the back of the bolt head)?"

And it still raises my eyebrows that someone would call out a published and well respected work as garbage. That says quite a bit in my book.

Blue Avenger
01-31-2010, 01:47 PM
some of that sear resistance against the trigger?

sharpshooter
02-01-2010, 01:39 AM
I doubt it's that much resistance, especially since I run a lightened or well worn sear spring. Take a look at that small torsion spring on the sear and compare it to the mainspring. See how much leverage the upper sear tab has on that torsion spring. Also, remember, that's a ramp on the sear. The cocking pin has LOTS of leverage on it. And what's more, that leverage increases as the sear drops out of the way (the ramp gets shallower). Most of the resistance will be purely frictional there. So yes, I call it negligible and include it in the safety factors between 75 oz-in and what actually is needed to pop an ideal LR primer. It's nowhere near 6-8lbs once the trigger breaks.
You doubt that it is that much?? Evidently you have never measured it. And yes, it can be measured.The sear resistance is there for the whole travel of the firing pin. It is hardly negligable, unlike firing pin drag.
Another way of looking at this whole situation is as a closed system. At the end of the day, the input is a 90* throw w a force at the end of a lever arm, torque. That is an input energy that's converted to stored potential energy in the mainspring. That energy is then released to strike the primer. So, the only way to get a lighter throw is to decrease the energy of the primer strike, bottom line. And there's a number of ways to accomplish that.
I can see that you are truly clueless. You need to put away the books and the calculator and just study actions; alot of them. After a few years of hands on experience and visual inspection, you might get an idea of what really goes on in the operation of a bolt action.
Can/will anyone here answer my question?:
"How can the firing pin possibly travel further than from the top detent to the bottom of the ramp (or the back of the bolt head)?"
You need to examine a Winchester model 70.
And it still raises my eyebrows that someone would call out a published and well respected work as garbage. That says quite a bit in my book.
I never said it was garbage, I just said his data was incorrect. I don't suppose he spent a decade researching just the Savage. Just because it is in print does not mean it is carved in stone as a fact, many respected authors have made mistakes.

Smokepole
02-01-2010, 10:48 AM
I think the lights just went on. I don't have a model 70, but I've been studying the cutaways and prints for awhile (at least the ones I can find).

And as far as 'hands on experience' goes, my 110 and 10 w the light firing pin springs are shooting just fine. No primer blanking, good uniform strikes, no misfires, and a greatly reduced throw.

Smokepole
02-01-2010, 12:41 PM
Do you have anything of value to add to this discussion? Any detailed information?

groupshooter22
02-01-2010, 01:47 PM
Typical engineer! Too much time with books and not enough time actually doing.

Smokepole
02-01-2010, 02:08 PM
Now, back to the 'value added' portion of the discussion. It appears that the cocking sleeve on the model 70 is rigidly connected to the firing pin. Upon opening the bolt and cocking, the cocking piece rides up a cocking ramp in the bolt body. It locks in a detent. Simultaneously, there's some motion going on w the cocking sleeve as it threads into the bolt body. Depending on the direction of the threads, it'll either help preload the spring more or less upon closing. The bolt is cycled, then the handle is closed. Upon closing, the cocking piece rests on the sear before the closing cams engage. The bolt sleeve/shroud threads in or out of the bolt body during the rotation depending on the thread direction (again this could either serve to help preload the mainspring or relax it some depending on thread direction). The closing cams on the lugs preload the mainspring even more than the cam did. So, I neglected to add in my closed system the closing of the bolt! I agree, that was careless indeed (not clueless though). So, you get mainspring compression from the cocking ramp and from the closing cams. I suppose on time and trues the recutting of the closing cams allows more firing pin travel. The added closing cam draws the bolt forward more than stock while the cocking button is already resting on the sear.

So, recutting the cocking ramp shallower lessens the bolt opening force, as does the lighter spring. And the recutting of the closing cams on the lugs adds to closing effort, but not noticeably. It would gain firing pin travel over stock since the closing cams would be more aggressive, drawing the bolt forward faster. All of that should explain it in conceptual terms. And it explains my fault in logic that firing pin travel can't be more than the cocking distance of the ramp. It can't be more than the sum of the cocking distance of the ramp and the cocking distance of the closing cams would be the correct statement.

For me in particular, I wanted to try the lighter spring since I have access to a lathe and could true the action face and nut off myself. I don't however have a good way to recut the cocking ramp or closing cams. The only thing I lose from the vendor approach is a little lock time on an action that can afford to loose some, but I get to keep my $125. Another thing I could try is to optimize the sear timing w the stock closing cams. I might as well make sure that I'm getting the cocking button resting on the sear at the same time the closing cams start engaging. That way I get the most firing pin travel possible.

And, as for the random anti-engineer comments, get real. The difference between an engineer and a scientist is application or hands on abilities. A scientist thinks things up (DaVinci). An engineer thinks things up and creates them. Thank your lucky stars you have a civilized world to live in based on the accomplishments of the engineering fields. However, I do not deny that there are many sub-standard engineers out there that flat don't know what a pair of channel locks are. I work w a couple. :o

And, I went back and modified a few of my posts for clarity and so that nobody gets any misinformation by not reading all the way thru the thread.

chestsprings
02-01-2010, 03:39 PM
And, as for the random anti-engineer comments, get real. Put up your childish jealousy. Thank your luck stars you have a civilized world to live in based on the accomplishments of the engineering fields.

Nothing like a person breaking their arm, patting them selves on the back.

Talk about an "EGO "

WOW

Smokepole
02-01-2010, 03:50 PM
I don't find it egotistical at all. I thank doctors every chance I get for their commitment to getting a proper education to better our standard of living. I thank plumbers for cleaning pipes. I don't particularly want to thank telemarketers, but I guess they have their place. Point is, every job has an inherent value. Mine does too. So, several here belittling it is no different than me belittling your occupation, whatever it is. So sure, I'll call you out and put an appropriate stop to it.

You're typing on a PC made of engineered polymers w silicon microprocessors that were engineered. The very construction of the machine itself was designed by an engineer. The wires carrying the signal were too. Practically all aspects of modern life were made possible by an engineer at some point. It's unbelievably egotistical on your part not to realize that when you're using/enjoying the actual fruits of the labor of the group of people you are condemning. If you think it's me patting myself on the back, that's fine, but it was surely not my intent.

chestsprings
02-01-2010, 05:30 PM
I’m glad you understand every one has a skill, just not engineers.

If you want to discuss how a phone conversation, or data goes from point “A” to any where in the world, by optical switching, using time division-space division switching, then I’m your man. As far as mechinal engineering, not me.

If you think that all the other skills that people have, had not contributed to civilization, only engineers, you need to come out of your hole.

The vast majority of people on this Savage forum have a skill which has, & does contribute to civilization No matter how insignificant some people think it is.

People, who think there skill is the “only one”, need to take their attitude to the “24 hr. campfire”, forum, as they seem to have quite a few people with that attitude.

It seems like some comments about engineering, & your opinions, were made because of your attitude that you know more about the topic than others. You may, & in my case, you do, compared to others, I’m not impressed.

You may not have meant it that way, but you sure came across that way.

Sharpshooter comment:

“The data I collected was passed on to John Peirce(Peirce Precision Engineering) for calculation and then to Bruce Thom (BAT Actions) for confirmation.”

Your response: It's not calculus in this case; it's algebra.

Where did SS say any thing about “Algebra”, he said, “for calculation”

You:

“Do you have anything of value to add to this discussion? Any detailed information?”

“Mine does too. So, several here belittling it is no different than me belittling your occupation, whatever it is. So sure, I'll call you out and put an appropriate stop to it”.

This attitude that only one person’s opinion on a subject is the correct one just doesn’t fly.

Opinions are the results of a person’s experiences. That’s why there is a difference. Doesn’t mean one person is right, or one is wrong, only that their opinion (experiences) is different.

I think you need to step back, take a BIG breath, un-wrap that big wad in you underwear, & listen, & not try to push your view point down people’s throat.

Also, have a good day.

Smokepole
02-01-2010, 05:54 PM
Actually, maybe you should read a little closer:

Sharpshooter:

"Because I'm not that great at calculus, I put that task to someone that is."

So yeah, I stated it's not calculus, and it isn't. Sure, the end algebraic relation is derived from calculus, but, in the end, in its most simplified form, the relation in question is algebraic.

And I'd appreciate it if you'd edit your post. I think you meant to say: I'm glad you understand everyone has a skill, not just engineers. If you meant to say what it reads, that's a different story.

You're taking my quotes way out of context. Read it as a whole and take it for what it is---a defense against some folks busting my chops. You're feathers would be ruffled as well. And, my occupation and training does qualify me much more than the general population to comment on such things. This is not a board about telecom, being a good florist, being a good cook, oil well drilling, etc. It's a forum about machines that fire projectiles. I'm sorry, but that's the way it is, and you said so yourself:

"You may, & in my case, you do,"
"As far as mechinal engineering, not me."

See what things sound like when you pull them out of context? Again, I'm trying to pose an alternate way to go about lightening bolt lift rather than the $125 way. Seems that goes against this forum's way of doing things. It isn't a difference in opinions. It's an alternate path to a similar result. And, I am simply trying to sift thru this 'cloak of secrecy' if you will to find out exactly what I'd get if I elected to send my $125 and action to a particular vendor. It's not a crime nor is it wrong to find out what you would get for your money.

Docs know more about anatomy than me. You obviously know more about telecom than me. But at some point you'll wind up at mechanical engineers, and they know more than most on mechanical things or at least have the skills and training to problem solve and innovate concerning particular mechanical challenges as they come to them.

This isn't a discussion about career choices and areas of expertise. I just want to get a better picture in my head of what that $125 worth is. I think I've got a real good idea now.

I got out my 110 and did some caliper work and inspection on it as suggested. Mine has about .315 of cocking cam. There is no cocking upon closing. The lugs are riding on each others' parallel surfaces by the time the cocking button rides down the cocking ramp far enough to engage the sear. That, indeed is disappointing. The upside is, that I can probably do some tweaking to the lower sear tab to get it to engage the cocking button sooner. That would provide for some cocking on closing, which would provide some more striker energy. But so far, my testing has proven that I don't need it, and I'm satisfied w my one finger bolt lift as-is. The sear resistance is about 34 oz or a little more than 2lbs, nowhere near the suggested 6-8lbs that was stated earlier. The force needed to drop the sear down ramps up as its torsion spring is compressed, and as soon as 34 oz hits, the cocking button is cleared from the sear (I know it won't do that in use). Indeed the sear does hold some resistance, but no more than 34 oz in my case. Once that force is reached, the sear is gone out of the way. So, by that line of thinking, my mainspring has to push an extra 2lbs of resistance that isn't transferred to the primer. But I'm confident that it's well absorbed in the padding I mentioned earlier. And my testing proves that so far, in my rifle.

chestsprings
02-01-2010, 08:30 PM
And I'd appreciate it if you'd edit your post.

YES SIR. Excuse me, I Will do as you request.

Dang!!!!!

I did mis-place the two words, “not, & just”. My fault.

That’s 200 lashes with a wet noodle on me from Smokepole

O!!!!!!!!!!!! there I screwed up again. I mentioned “noodle” a food product, especially when:

This is not a board about telecom, being a good florist, being a good cook, oil well drilling, etc. It's a forum about machines that fire projectiles. I'm sorry, but that's the way it is, ie.
Again, I'm trying to pose an alternate way to go about lightening bolt lift rather than the $125 way. Seems that goes against this forum's way of doing things. It isn't a difference in opinions. It's an alternate path to a similar result. And, I am simply trying to sift thru this 'cloak of secrecy' if you will to find out exactly what I'd get if I elected to send my $125 and action to a particular vendor. It's not a crime nor is it wrong to find out what you would get for your money.

You are not naïve enough to think SS is going to tell you how he tweaks the T&T, after he spent countless hrs. figuring it out. Tell us all, why should he?

I don’t know SS personally, but he seems to take time out from his busy work to answer/help every one on this forum with reasonable questions.

My simple response, if I was SS to you would be, if you don’t want to spend $125.00 for me to do it, don’t. Simple as that.

A lot of people seem very satisfied with his T&T, as it seems, he has quite a back log.

Last post for me on this, as I am one who can “get on with life” ;D

Smokepole
02-01-2010, 09:22 PM
Really, at this point, I finally gleaned enough to answer my own questions. I expect nothing. Forgive me if I'm a slow learner. I was thinking closed mindedly about the Savage only. From the factory, mine has no cocking due to anything but the cocking ramp. The integral lug ramps do no cocking on mine. That had me bumfuzzled, but I'm not anymore. After the clue about the Model 70, I closely examined a couple of my other actions and I examined cutaways and prints of the 70 to realize what goes on in them. And, indeed, it's glaringly obvious once you know. And the fact remains that my solution is still working just fine, and it doesn't cost $125. And that sear resistance obviously isn't what it was implied to be earlier. What's troubling is that nobody seems interested at all. Guess their money isn't worth as much to them as it is to me. That or the select few that actually know anything about what I'm talking about, aren't speaking up. This site should be about more than just swapping barrels, triggers, and other components sourced from vendors....

mgs44mag
02-01-2010, 10:03 PM
Ever reverse engineer something?? You know, get it to work and them figure out what works and what doesn’t. I can’t tell you on how many countless occasions I have had to hold some engineers hand over what should theoretically work and what actually works. I would be the tool maker on the floor saving your hinny.

SSS should definitely keep his trade secrets. That’s how he makes a living. It's obvious you wouldn't be satisfied with the process anyway. Just think if you had to explain every key stroke you used on let’s say Solid Works to draw an object, insert a bolt that is already on file and make the parts move as they would when in use. Do I need that info to do my job? No.

What bugs you is that no one is going to give you the info or do it for you. Similar to some of your other posts. You love to hear yourself think out loud (in posts) so others will believe the info bubbling from your lips.

Besides, you’re saving $125. What more could you want?

Once again, I’m the tool maker making over engineered projects work.

Bark
02-01-2010, 10:26 PM
Yes sir,got my moneys worth on calories burned to post the original question.Even after the balloon went up a bucketful of very good info.to process.I personally want to thank Smokepole for sharing his experiences and methods.Also,I would like to thank Fred for throwing in and providing an excellent trigger for my first Savage rifle project....first of many no doubt.I like Savageland.It's like the old days in cars and bikes when it wasn't a requirement to have a breakout box to change a taillight bulb-you can hands on and if you bugger it up grab a couple parts and get back after it.Savageland.Just seems more good ole boy then Remmyworld,a lot less UPS.Just started humming "chest..nuts roasting on an open fire...",don't know why.Again,thanks to those who added and to those that showed up just to kick up dust.....bet ur dirt-dancing card stays plum full 24/7. Old Grumpy Bark

Smokepole
02-01-2010, 10:32 PM
mgs44mag, you really have no clue what engineers do. And you sure have no clue what I do. Your arrogance shows your ignorance. And you have no idea what my motivations are; pure curiosity. I figured that would be blindingly obvious. And what's more, SSS has conceptually explained the so-called 'trade secrets' over on 6mmbr in pretty good detail. If I'd read that, and read more about the other actions in Otteson's book (or had I simply picked up my other rifles!) this thread wouldn't exist. Those trade secrets are merely the incorporation of features commonly found on other bolt actions onto the Savage. Which also explains why it's not patentable; it's not original, and it's no secret. And, the fact is, if anyone is interested in straight up copying and marketing the exact work, all it costs is $125 and you can reverse engineer away no matter how big of a copout that is.

All of this discussion on my end was simply trying to reconcile what works and what doesn't with my own thoughts. I think I've done that. If someone feels like they can get something out of it all, please read it. If not, don't.