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Falling block accuracy?
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This thread is meant to start a discussion, and later on to present some ideas I have for debate.

The question is, can a falling block action be as accurate (reliably so) as a good bolt action, and how would one go about it? The question is NOT whether there is any point in doing so. That is a different debate in which I feel would only muddy the waters at this time.

There have been many discussions on the accuracy of the Ruger no.1 (the reason I believe this action is most often debated is that it's the only falling block available in reasonable quantities to generate such debate) for example, with some guys reporting great results, some reporting bad results and some reporting mixed results. Some say "bad" no.1's can be fixed while others say they have tried everything to no avail, but even so, I think most guys evaluating the accuracy of a no.1 are really measuring them against the requirements for hunting applications. However, nobody I have heard of in the last half a century at least has tried to use a falling block rifle in the kind of competitive shooting where accuracy is the primary requirement (such as F-class, "Bisley" or benchrest).

Clearly, actions like the Ruger No.1, the Hagn and the once-successful Farquharson have been left behind and exist today primarily for their aesthetic qualities and nostalgic reasons.

Of course, a large part of the difficulty here is that the action is probably one of the least influential parts of the system as a whole, with shooter skill, ammunition quality (and how well it is matched to the rifle) and barrel quality all playing more important roles.

But, if one were prepared to compromise on the aesthetics, would it be possible to design a falling block of comparable accuracy to modern bolt-actions?

In order to design something, I feel the best place to start is by asking questions, and the most important question in this regard is probably to establish what elements in an action's design have an impact on accuracy.
Here's my take:
1) The most important element is to hold the barrel, stock and (usually) the sighting system together accurately, in such a way that barrel harmonics are not affected by any external factors (such as the stock swelling or crimping, the shooter's hold and shooting position and so forth).
2) The second (and I suspect this is to some extent debatable) is to hold the cartridge contained in a space that remains the same shape and size as far as possible (IE the chamber is part of the barrel and the breech face remains square to the chamber and with minimum "stretch" or change in the "headspace" (maybe not the ideal word but I can't think of a more understandable one) during the process of firing a shot. I think this is somewhat debatable because the general frame of reference is that rifles are usually constructed in such a way that any angular movement of the barrel relative to the breech face translates directly to a similar change in the angle of the barrel to the stock and usually also the sights, as the receiver is usually the component mounted to the stock, with the front-most mounting point usually being very close to the breech face. I know of some experiments where people have mounted a portion of the barrel (usually the area directly around the chamber) to the stock while free-floating the action, and I know that most people who have tried this swears that it improves accuracy, but the results are perhaps not so massive as to convince everybody else of the same, or else such a construction would have become common.

However what is undeniable is that bolt actions which are designed primarily for accuracy tend to incorporate features which try to address the above points, with receivers usually compromising chamber access in favor of stiffness, a trend toward bolt heads with multiple locking lugs distributed evenly around the circumference and the modern trend toward aluminium "chassis" to eliminate atmospheric dimensional changes and generally add more stiffness to the relative relationships between the components (the shooter being one of the components).

I herewith welcome your thoughts on the matter.
 
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I think a competitive falling block could be made. It'd probably have to have a 1 piece stock and it'd likely have to be side load/eject (vs top eject) to allow a top strap for stiffness. Maybe some revision of the DIY design Frank Haas put together for his book on building the single-shot action.
 
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Peter,I am very interested and look forward to the discussion. Thanks for presenting it.
 
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The Mauser '03 and Blaser's(and others) showed that bedding the barrel and floating the action produce very accurate rifles. Why not do the same with a falling block? One piece wrap around stock. Action free-floated inside. Barrel secured by two screws bedded to the stock with recoil lug and free-floated. Just need to machine a heavier breech section.
 
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Accuracy is largely a matter of barrel vibration/harmonics. Prior to firing as little as possible vibration must be introduced to the barrel; small fast moving parts involved in ignition.
 
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Thanks gentlemen

skl1, I would like to understand why you feel side loading and ejection would be an advantage if you consider that:
1) There isn't really a "top strap" behind the breech on a falling block action, nor to my mind any reason to have one unless you have a sight mount or bedding screw somewhere behind that point? Surely, a side port adds more disadvantages than it takes away as you either need to cut through your locking surfaces, or move them much further back (introducing more length of material to flex), or have the block move sideways (which might end up with a very wierdly-shaped rifle)? With regard to the Miller-De Haas action, I did draw inspiration from it in that I have the complete "fire control group" mounted in the breech block.

gwahir, yes, a straight-line striker directly on the bore axis and of very low weight is part of my concept. Of course this does have a couple of slight disadvantages. Firstly, the breech block needs to be longer to fit the striker's spring and secondly the action will be more difficult to open as the spring needs to be stronger than one used with a heavier striker to ensure good ignition.

Bobster, that's where I started but I ended up somewhere quite different.
 
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So here is the concept (let's see if I can still remember how to post images):


The receiver's "front ring" is massively elongated (it is nearly 4" long). This elongated section is what the whole rest of the rifle mounts to. Optic via a built-in dovetail rail machined at 20MOA pitch.


The stock is mounted/bedded via a recoil lug, a central rib and FOUR bedding screws.


And barrel. Because a thread does not give a precise concentric location, only the first 1.25" of this section is threaded. The rest is a reamed hole which should give very precise alignment (I hope). Barrel retention can be done with an integral shoulder or a separate nut as I have shown it here.

As can also be seen in the image above, the locking shoulders have been kept close to the breech face. This reduces the amount of deflection for a given applied stress.


In this sectioned image, the fire control parts can be seen. A simple compound-sear mechanism and fully adjustable trigger is proposed. All adjustments can be made without dismantling the action, but the breech has to be opened. Length of trigger pull is adjusted via an eccentric bushing seen just behind the vertical portion of the trigger.


In the above sectioned image, the section plane is coloured blue. What I am trying to show here is that the sides of the action are machined very thin in the bottom section. This is done for two reasons. Firstly, this is to keep the wrap-around one-piece stock reasonably thin at it's widest point, but also this means that the bottom half of the action will flex quite easily. This results in the effective recoil shoulder or "locking lug" area being virtually symmetrical above and below the bore centreline (in the hope that the breech face thus remains absolutely square to the bore centreline), yet still provides a long channel for the breech block to travel up and down in, ensuring smooth, accurate breech block travel.


This last image gives an idea of what a rifle built on this action might look like. This particular stock is a light-weight aluminium job which is perhaps not perfectly in keeping with the stated intent, especially for most forms of competitive use, but that's easy enough to change.

Just some comparative figures for the nerdy:
I compared it to a Musgrave RSA, an old single-shot target bolt action made in South Africa which was once extremely competitive but has been left behind in recent years, but unfortunately the only target bolt-action rifle I had sufficient access to for accurate measurement during the design phase.
Action weight: 1kg (RSA is 1.25kg)
Calculated "active change in chamber length/headspace": 0.0165mm. This is for a .308-sized case head at 430mPa (max allowable SAAMI chamber pressure). For the RSA (and since it is closely based on a Mauser 98, by extension also most commercial two-lug bolt actions), this figure would be 0.049mm or 2.97 times greater. This ratio is basically equivalent to how much stronger the action is, thus this action is potentially safer in a catastrophic event.

Some advantages over a bolt action not specifically related to inherent accuracy but possibly relevant to achieved accuracy:
1) The barrel can be 130mm longer for the same total rifle length.
2) Action is 100% ambidextrous.
3) Action is lighter, so if there is a weight limit, the weight can be distributed better for rifle balance or barrel rigidity.
4) Because the breech face is closer to the shooter, I believe that this could be re-loaded with less disturbance to the shooter's position.

Any concerns or comments?
 
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The whole concept is an exercise in frustration and still uses a cheap and easily available off the shelf bolt action as a performance bench mark.

Do it for fun if you want but don't expect to "disrupt" the bolt action based bench rest shooting world with it. All of your potential advantages have been addressed already in competitive bench rest circles.

Don't get me wrong, I am not a bolt action snob. In fact, I only have two which include the first rifle given to me as a kid and a 50 BMG. My interests in collecting, hunting and fun are traditional styled single shot rifles knowing in advance that they have their quirks and will almost never be as accurate as a $300 bolt action rifle from Wally World.

I did build a TC Contender (break action) in 22lr around a barrel block in a one piece wood stock about 20 years ago just for fun. It shoots OK but it is heavy and a bit clumsy to handle and really only works using a wide front shooting rest. I'm glad I did it but I have not shot it much since then.
 
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Mike, I have no expectation of disrupting the market. I don't even really expect to sell a single one. If a gunsmith wants to try make one (or a few), he can have the drawings for free. This is NOT a commercial venture.

To me, it is just an interesting conundrum.
 
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Why not a "standard" falling block action, use a barrel clamp to mount the rifle to the stock and attach optics to.

Been used for decades in the BR circut.
Obviously you can slim it more down.





 
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Peter, the Hauck single shot falling block was designed to compete with the bolt actions off the bench in the fifties; might be of some interest to you.
 
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Nortman, it could certainly be done and that is actually exactly where I started off this journey. My concern with that approach is how wide/thick the stock becomes to go around the action. I think it would make for an extremely unwieldy action, although for BR and Bisley that probably doesn't matter.
Furthermore, it assumes that the only problem with other/current falling blocks is the way they attach to the stock. In this action, I have taken a lot of other factors into consideration. Whether or not those factors are in fact relevant to accuracy, I just don't know.

Gwahir, thanks for that, I was not aware of that action. It is an interesting and well thought-out action, addressing several common problems elegantly and simply. However, it only addresses a few of my ideals.
 
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An Aluminium "middle part"/bedding block to attach the two parts of the stock would take care of the problem with mounting the foreend most falling and break action seems to have. A long and heavy mounting piece for the barrel would take away the reason for wanting a falling block.
 
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http://www.huntingriflesreview...3-Arabesque-main.jpg

Above is a pic of a Mauser 03 with barrel. This is all you need with a Ruger No 1 action screwed on. Stock could be overmold with aluminum bedding rail. Carried a step further, the action could be made to facilitate changing barrels.
 
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quote:
Originally posted by Bobster:
http://www.huntingriflesreview...3-Arabesque-main.jpg

Above is a pic of a Mauser 03 with barrel. This is all you need with a Ruger No 1 action screwed on. Stock could be overmold with aluminum bedding rail. Carried a step further, the action could be made to facilitate changing barrels.


Sure, but then you still have a heavy swinging hammer and locking surfaces which are not symmetrical to the barrel (I still don't know whether that is in fact a source of inacuracy, but I believe it could be). As a rifle for anything other than benchrest, you also have a very thick stock, as the action is 35mm wide and you need to take the stock around it. Thus the stock would have to be at least 47mm wide around the action?

My question is not "what can be done to make an existing single-shot action more accurate" but rather "what are the factors in an action design which affect accuracy, and can a falling block action which incorporate all of them to a similar or greater extent than any currently available bolt action"?

Thus, the question I am really asking is, is there any known design element in the action presented above that would be detrimental to the goal of achieving the best possible accuracy?
 
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Peter, I question the need of the extended front of your design. I think that I have accomplished the same thing by using a rather thick spacer between the front of the receiver and the barrel. The spacer is threaded and a tube for end screws on to it. The scope can be mounted on the tube. Nothing touches the barrel. I think the extended front ring would be prone to stretching, like an action with rear locking lugs.
 
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Peter, I see no advantage to a one piece stock. A two piece with the butt stock attached with a good size thru bolt is far more solid.
 
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quote:
Originally posted by Peter Connan:
quote:
Originally posted by Bobster:
http://www.huntingriflesreview...3-Arabesque-main.jpg

Above is a pic of a Mauser 03 with barrel. This is all you need with a Ruger No 1 action screwed on. Stock could be overmold with aluminum bedding rail. Carried a step further, the action could be made to facilitate changing barrels.


Sure, but then you still have a heavy swinging hammer and locking surfaces which are not symmetrical to the barrel (I still don't know whether that is in fact a source of inacuracy, but I believe it could be). As a rifle for anything other than benchrest, you also have a very thick stock, as the action is 35mm wide and you need to take the stock around it. Thus the stock would have to be at least 47mm wide around the action?

My question is not "what can be done to make an existing single-shot action more accurate" but rather "what are the factors in an action design which affect accuracy, and can a falling block action which incorporate all of them to a similar or greater extent than any currently available bolt action"?

Thus, the question I am really asking is, is there any known design element in the action presented above that would be detrimental to the goal of achieving the best possible accuracy?


A Mauser LR action is 35 mm in diameter. Nobody seems to think that stock is too wide. I think the biggest contributors to inaccuracy in single shots are a short barrel tenon and the forend hanger. Screwing the barrel to the stock eliminates both of those concerns. You could design a two piece stock that has a buttstock attachment like a SMLE. Then a longer receiver to support a longer tenon. Lastly, eliminate the forend hanger and use an attachment system like the forend on a semi-auto shotgun. Essentially a tube screwed/brazed into the receiver below the barrel that the forend attaches to. Totally independent of the barrel. Then you would have a rock solid recoil shoulder combined with barrel/receiver rigidity. Also a free-floated barrel.
 
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quote:
Originally posted by gwahir:
Peter, I question the need of the extended front of your design. I think that I have accomplished the same thing by using a rather thick spacer between the front of the receiver and the barrel. The spacer is threaded and a tube for end screws on to it. The scope can be mounted on the tube. Nothing touches the barrel. I think the extended front ring would be prone to stretching, like an action with rear locking lugs.


Amazing how one can stare at something for months without seeing the obvious. Thank you.

With regard to two-piece or one-piece stocks, I agree that a well-constructed joint between the but and the action is probably stiffer than a wooden one-piece stock. But I feel that there will probably always be some flex somewhere, and by stiffening that area, you may be transferring the movement to a less advantageous position, such as the barrel/receiver joint or the action side-walls.
 
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quote:
Originally posted by Bobster:
quote:
Originally posted by Peter Connan:
quote:
Originally posted by Bobster:
http://www.huntingriflesreview...3-Arabesque-main.jpg

Above is a pic of a Mauser 03 with barrel. This is all you need with a Ruger No 1 action screwed on. Stock could be overmold with aluminum bedding rail. Carried a step further, the action could be made to facilitate changing barrels.


Sure, but then you still have a heavy swinging hammer and locking surfaces which are not symmetrical to the barrel (I still don't know whether that is in fact a source of inacuracy, but I believe it could be). As a rifle for anything other than benchrest, you also have a very thick stock, as the action is 35mm wide and you need to take the stock around it. Thus the stock would have to be at least 47mm wide around the action?

My question is not "what can be done to make an existing single-shot action more accurate" but rather "what are the factors in an action design which affect accuracy, and can a falling block action which incorporate all of them to a similar or greater extent than any currently available bolt action"?

Thus, the question I am really asking is, is there any known design element in the action presented above that would be detrimental to the goal of achieving the best possible accuracy?


A Mauser LR action is 35 mm in diameter. Nobody seems to think that stock is too wide. I think the biggest contributors to inaccuracy in single shots are a short barrel tenon and the forend hanger. Screwing the barrel to the stock eliminates both of those concerns. You could design a two piece stock that has a buttstock attachment like a SMLE. Then a longer receiver to support a longer tenon. Lastly, eliminate the forend hanger and use an attachment system like the forend on a semi-auto shotgun. Essentially a tube screwed/brazed into the receiver below the barrel that the forend attaches to. Totally independent of the barrel. Then you would have a rock solid recoil shoulder combined with barrel/receiver rigidity. Also a free-floated barrel.


The Ruger mark one is built so that the fore-end can be free-floated, attached only to the spring hanger. Yet I have heard of cases where doing this did not solve accuracy problems with individual rifles. Lee Enfields are known to be extremely finnicky about how the forend is set up.

Remember that on a typical falling block, the action is the same width top to bottom, whereas on a bolt action the receiver is basically round and at least half of it sticks out the top. The stock only needs to be wide enough to go around the magazine box (if there is one) or the trigger mechanism (in single-shots), which is far narrower. Thus, the stock goes under the receiver more than around it, which is not really possible with a conventional falling block.
 
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In the beguinning of the metallic cartridge era asymmetric locking lugs were not a problem in bolt actions.

1871 one single locking lug were not a problem for low pressure BP cartridges, the action could be made in iron too.
In the 1880s experiment with higher pressure BP rounds showed what a single locking lug wasn`t enough and warping of the action could happen after long service use. An extra asymmetric lucking lug were added to some late blackpowder bolt actions.
With the invention of smokeless and higher pressure most military rifles got the locking lugs moved to the front and in a symmetric position.
An exeption were the Norwegian Krag-Jörgensen which added a asymmetric locking lug for the 6,5*55 (improvement from the Danish 8mm Krag), then US later adopted the Krag the Springfield armory didn`t use the second locking lug as a support only as a safety feature with lose tolerance to be able to speed up production, this created a problem so 30-40 couldn`t be modernized with higher pressures.
Modern steel and a beefed up action can limit the problems of the asymmtric locking lugs.
 
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Peter, do not worry about the barrel/receiver junction! It strong and stiff. If we want to make it more stiff, I suppose we could weld the two parts together! Adding wood is not going to do it! (cynical today)
 
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Hauck innards.
 
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Hauck receiver size compared to ruger #1.
 
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quote:
Originally posted by Peter Connan:

skl1, I would like to understand why you feel side loading and ejection would be an advantage if you consider that:
1) There isn't really a "top strap" behind the breech on a falling block action, nor to my mind any reason to have one unless you have a sight mount or bedding screw somewhere behind that point? Surely, a side port adds more disadvantages than it takes away as you either need to cut through your locking surfaces, or move them much further back (introducing more length of material to flex), or have the block move sideways (which might end up with a very wierdly-shaped rifle)? With regard to the Miller-De Haas action, I did draw inspiration from it in that I have the complete "fire control group" mounted in the breech block.



Peter,

I was thinking of stiffening the action before seeing your proposed design, as well as trying to make the cut-aways in the action as close to symmetrical as possible above and below the bore line (per Harold Vaughn's "Rifle Accuracy Facts"). What I had in mind was a very odd-looking action, the DeHaas Vault Lock action.
 
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Peter, I see how your action does a good job of providing symmetrical locking support in line with the bore. Hauck does almost as well, either by design or by accident! Notice part #9 on the diagram of the Hauck. It is a dovetailed part that covers the required machine work in the back of the block. It's thickness extends well beyond the rear surface of the block, and only it carries the pressure to the rear wall of the breech block mortise. It is placed high on the block and pretty much inline with the bore, so that is where the force goes! It is good when it all works out!
 
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quote:
Originally posted by gwahir:
Peter, do not worry about the barrel/receiver junction! It strong and stiff. If we want to make it more stiff, I suppose we could weld the two parts together! Adding wood is not going to do it! (cynical today)


I have noticed that on many actions specifically intended for better accuracy, the front receiver ring is made longer than on most "normal" actions.
Your Hauck action is one of them, the barrel thread being roughly twice as long as on the Mauser 98. So, I do think that I am not alone in thinking that this factor is a possible contributor to accuracy.

With regard to the dovetail plate, yes, I did see that. Other factors on the Hauck I really like are the vertical main-spring (great use of space but unfortunately that limits one to a swinging hammer), the very short stroke of that hammer (which will obviously reduce the problems caused by such a hammer), and that it appears to mostly cock on closing.

The massive receiver will surely reduce how much the action flexes.
 
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quote:
Originally posted by skl1:
Peter,

I was thinking of stiffening the action before seeing your proposed design, as well as trying to make the cut-aways in the action as close to symmetrical as possible above and below the bore line (per Harold Vaughn's "Rifle Accuracy Facts"). What I had in mind was a very odd-looking action, the DeHaas Vault Lock action.


A very interesting action, thank you.
I am sure it works very well. The BSA International achieves a similar result, but very different in execution.
 
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quote:
Originally posted by Nordic2:
Modern steel and a beefed up action can limit the problems of the asymmtric locking lugs.


In terms of firearm durability and operator safety, I agree completely.

However, with respect to it's possible effect on accuracy (and note that I am not 100% convinced that it has ANY effect on accuracy on it's own), I don't think modern steel plays any role at all. The Young's Modulus of Elasticity (a value indicating how much a material deforms upon the application of a given force) of steel is almost the same for all steels from normal Mild steel to the strongest of modern alloys.

Obviously just making it bigger does reduce the amount of deformation.
 
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Peter, the Hauck hammer pretty well pivots on it's center of mass; it's movement on the way to the firing pin does not create disruption. The same cannot be said for a striker system! It is important that the movement of the hammer is stopped by the firing pin as it indents the primer. We do not want the hammer (or striker) to hit the block!
 
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Peter, your breech block is set at about a 5 degree angle to your bore, like a lot of the traditional single shots, in order to aid in seating a cartridge and to give the extractor room to function. So. The force is being absorbed by a surface that is not at a right angle to the bore! Do we want to do this? Hauck did not.
 
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Gwahir, why do you feel a striker creates a greater disruption? Sure, it creates a movement forward at the moment of firing, but i suspect all impact-ignition systems would, and since the striker is the lightest, it should have the least impact? the effective mass of mine's striker (striker plus half the spring) is just 14g (216grain).

With regard to the 5 degree angle, I agree that it is less than absolutely optimal. However, for safety reasons I did not want to cut through the chamber wall as far forward as Hauck had to do to get enough extractor movement to make the rifle usable. The other alternative would be to pull the block down further, but then the top surface doesn't support the case coming out anymore, so it could hang up on the rear end of the receiver. I guess that could be removed as well, but not without other consequences.

Also, I am playing an odd balancing game. The actual cross-sectional areas of the side-wall above and below the bore centerline are not exactly equal. The formula I used takes into account the difference in average length, in order to get the same amount of deflection. Again, not sure if this will play out in reality, or even if it matters.

With regard to whether or not the 5 degree angle would result in the block moving upon firing, calculation shows that the friction coefficient would have to be less than .0875 for that to happen. And I am sure it won't be.

With regard to the problem of the forward section of the action stretching, I think extending the thread to within a couple of mm of the extractor cut should solve that problem. In that way, a small section of reamed bore still exists to ensure concentricity.
 
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Peter, I think if a hammer rotated on it's center of mass it could not disrupt. I think that disruption could only happen if mass is moved. I am saying 'I think' rather than 'I know'! The only other hammer I see like this is what de Haas refers to as a Kettner. I expect it was Hauck's inspiration for his action design. The rest of the hammers in the single shot world do not pivot near their center of mass. The Hauck would if some weight were removed from the upper part of the hammer. It is close as is.
 
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Peter, as you very well know, design work is a constant matter of compromise. Nothing has taught me that more than a Hauck extractor! I am considering a side extraction and am looking at the Ruger system. I do not want the ejection; just the extraction. I am building another Hauck, so it might happen.
Falling block/bolt action accuracy? From a design perspective, I am not convinced either has an advantage over the other, the bolt action is, however, easier to make.
 
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quote:
Originally posted by gwahir:
Peter, I think if a hammer rotated on it's center of mass it could not disrupt. I think that disruption could only happen if mass is moved. I am saying 'I think' rather than 'I know'! The only other hammer I see like this is what de Haas refers to as a Kettner. I expect it was Hauck's inspiration for his action design. The rest of the hammers in the single shot world do not pivot near their center of mass. The Hauck would if some weight were removed from the upper part of the hammer. It is close as is.


I am not sure that it is an apt analogy because of the drive system being completely different, but think of how much energy it requires to stop a free-spinning car wheel?
That hammer first accelerates and then has momentum, and both effects must be reacted somewhere.

You are certainly right about compromise. Virtually every decision you make creates a concern elsewhere.
I too am not a fan of ejectors. On my previous action (the 7mm shown in another thread) has a large extractor that grabs the case on both sides. In my case, it is actuated by the lever, and is extremely powerful. When building it, I made a very short "test barrel". It extended just 2mm past the shoulder of the case. To test the extractor I closed the action on a case and belled the mouth open, and still extracted it without difficulty.

On this action, the extractor comes up from the bottom like the Hauck because I specifically wanted it to work with the calibers familiar to the long-range bolt-action target crowd. It's actuation is very different though, being driven by the lever not the block, and is controlled differently as well. How well this will work remains to be seen.

Good luck with your build!
 
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And good luck on your build, Peter. Please keep us posted.
 
Posts: 261 | Registered: 02 December 2005Reply With Quote
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That is a difficult question and as I am not a BPCR shooter, I only have hear say about the accuracy of the black powder single shot rifles used in BPCR competition. But, based on what I have been told about group sizes at 300 yards, record ten shot groups at 300 yards are MOA or slightly less, which, is amazing in my opinion.

In my opinion, any rifle with a fore end hanging off the barrel will be less accurate than one with a free floating barrel. Now I do have a Ruger #1 that shoots exceptionally well with a few loads, but the rifle is not tolerant of ammunition changes. This rifle is first of all, not a target rifle. So any comparisons to bench rest accuracy are not apples to apples.







300 yards



600 yards



This rifle is hard to shoot as it has a heavy trigger that when released moves the rifle. It is also sensitive to where the fore end is on the rest.

And, it did not like these loads



Hard to know if it was the loads, or the rifle. A core lokt is not a target bullet.

With load development, there is no reason why a Ruger #1 cannot shoot as well as any run of the mill hunting rifle.

I believe my pre 64 M70's, glass bedded by me, are more accurate, and shoot a wider range of bullet weights well.









 
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Thanks Slamfire, very interesting observations.

I have also found that the one rifle I have with an aluminium stock seems to be pretty accurate with almost any load I stick in it, which is not the case with any wood-stocked high-pressure rifle I have owned.
 
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I am not certain the BSA Martini is a "true falling block", but then all definitions are man made and therefore artificial.

For a couple of years now I have been shooting imy BSA Martini collection in NRA , CMP, and ASSA Smallbore competition. More for the fun of it, and I have shot a BSA MKIII in three Smallbore Prone National Matches. For the fun of it.

I am going to claim that in my hands, I cannot determine if the inherent accuracy of a BSA Martini is any better or worse than an Anschutz or Win M52. The BSA Martini was an advanced rifle in 1960, sadly BSA did not improve the ergonomics and BSA smallbore rifle production ended in the 1970’s, I think.

However, when I am on a roll, I can shoot competitive targets.

This is a MK2, with an original Parker rear sight.




The Parker sight base was as loose as a goose and I had to put the thing in a vise to tighten things up. Once squished, the rear sight tracked correctly, and the sight is an 8th of an MOA affair. But the knob rotation is opposite from my regular iron sights, and in the heat of competition, it was easy to roll the thing in the wrong direction. So I installed a more modern rear sight.




Early handstop I fashioned.



that's the way they did it back then, handstops were only adjustable in one inch increments, while the real world is infinitely variable.




With a scope, this rifle is capable of shooting very good groups, despite a trigger that won’t go down less than 1.5 pounds.









I do shoot better with my MKIII’s, and that is the rifle I have used in the National Matches.






All match targets fired prone with a sling at 100 yards.



An exceptional ten shot group



A very good iron sight group.



I have a light barrel MKIV. The stock was cut short, so I added pieces of wood salvaged from a shipping pallet, nail holes and all, to extend the pull. While the rifle is accurate, the stock was a step back, and feels chunky and does not fit my hand or body well. BSA removed the MKIII hanger, so the forend is attached to the barrel with a screw.






The MK2 rifle, the fore end is attached to the barrel with a big center screw. The MKIII, the barrel is free floating. There is a heavy hanger on the MkIII that adds length to the receiver. I am of the opinion that the free floating barrel is and was un necessary. On both rifles, sling tension moves me out of position, and when I move out of alignment with the sights, the group moves. I therefore cannot tell if the MK2 is really sensitive to differing sling tension or not. It seems insensitive to sling tension variation.

A couple of things I really like about the BSA Martini action.

It is easy to pull the trigger mechanism out and clean the crud in the action recesses. I have not completely dissembled a trigger mechanism, I blow it out with compressed air and re oil.



The loading port is right in front of my nose, I don’t have to stretch out to load. It is fast to load for a single shot. Firing pin fall is faster than the bolt actions, though that is more a theoretical advantage than an actual advantage.

What I dislike, and what makes this rifle uncompetitive, is the ergonometrics. My hand is not well positioned to pull the trigger. It is impossible to get a comfortable and non stressed hand and arm position with the finger on the trigger and I see that on target. Pistol grips went away with cutlasses and flintlocks, the curve may be pleasing, but place the hand in an unnatural position. And then, no adjustable cheek piece, no adjustable buttplate, and the trigger is heavy compared to today’s triggers. It you look at modern competition smallbore rifles, they are adjustable in six dimensions, and time! These adjustments are critical for consistency. When the shooter has to bend, pull, stretch his body in un natural and uncomfortable positions, something will shift, and the bullet will zoom to regions unknown.

I do think had BSA improved the ergonometrics and trigger, this action could still be around and competitive. But they walked away from the market, and the market ran away from them.
 
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Thank you very much for that Slamfire.

Long have I coveted an International. They are quite scarce here. I have a number of older Martini's in my collection in various calibers, although only one was ever intended to be a target rifle. My .22 is a BSA Model 15 (like the one shown about half-way down the page here: http://www.adamsguns.com/martini.htm , but it has been fitted with a telescope and I made a new stock for it (to get my head behind aforementioned scope). While it is easily capable of knocking a coke can around shot for shot at 300m, it is not capable of the accuracy shown by your Mk.3. Or more probably I am not.

I do believe that action design (and stock bedding for that matter) is far more influential in high-pressure "full bore" rifles than in .22Lr, simply because the forces generated are so much greater.
The ergonomic advantage you mention during the loading cycle is one of the main reasons I like the idea of a falling block in prone competition shooting, but the issues you note with regard to shooting position are now concerning me. What do you feel could/should be done about this, and what do you think of my pistol grip design as shown in one of the pictures I posted earlier in the thread?

It is clear that the trigger mechanism on the International is a far more complicated affair than that of the older BSA's like mine however this is clearly still nowhere near as good as a modern six-way adjustable trigger. I clearly know too little about that. How does the time-adjustment work?

One thing I note with interest is how the barrel-to-receiver connection changed during the development of the International action, from a relatively normal short threaded connection to a much longer clamped connection. To my mind this to some extent vindicates my concerns about the short threaded connection seen in most actions, although of course it doesn't in any way indicate that my solution is any better.
 
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