Discussion in 'Advanced Gunsmithing & Engineering' started by fusionrider, Nov 5, 2008.
Nice build! You dont happen to have any blueprints on the tool for cutting the lug ramps?
I dont really have prints for it but, It is just a piece 1.5' 1018 CR with a 1' bore at one end and a .75' turning on the other. The bore to plunger fit is almost air tight and a vent hole was needed to get It to move freely. The cam was cut 90deg around the part and the appropriate drop,LUG OD x PI)/,4) to achive a 45deg 'ish' cut at the lug diameter. I used a .5' hardened dowel pin as the link between the two pieces. It works smooth and silky with a little way oil. Cutter geometry is kinda tricky but It worked well enough.
I have 20 years experience working with metal starting with my first job at a scab shop and working my way up to a national lab. One of my crazy ideas has always been to have a bolt action reciever, bolt, and a varmint barrel made from Invar 36, but enough about me.
Get your design on cad to best of your knowledge and personal style for starters.
Next thing is do is to work with a "experienced" machinist and get the nitty gritty on can it be made by a machinist? There are many ways to make a carbon fiber or stainless steel action. Machining and EDM are not the only ways. In fact EDM is not necasary with this project unless you break off a tap or are using a pin .015" in diameter. This is why you dont see an enginneer first. Working with the machinist, fabricator, or what ever skill set needed to make the action, make the design changes. Skilled trades people have sometimes fantastic ideas that make parts easier to make, cheaper to make, and some times just are way cooler to look at in the end.
Once the design meets your likings, have it engineered by a "mechanical" engineer. Odds are that there will be some changes to be made for whatever reasons, and working with the engineer, come up with solutions.
Once it is to your liking, go back to said tradesman and see if it is still a make able design.
Engineered takes on a whole new meaning if you have any knowledge of engineering or not, but it just may be the difference in a suicide or a new craze in benchrest. I am no way an engineer, but working along side them has opened my eyes greatly when it comes to design and troubleshooting. It could be the very first tiny detail in a designsmall foundation that causes a major breakthrough in diagnosing problems once the product reaches trial.
Given the date of this thread, as you may be aware, chrome moly is on a rise again in terms of popularity, so you know you can not go wrong with chrome moly I personally would go with a carbon steel with a bluing to costs down and once the rifle meets and exceeds your expectations, I would build it out of a more exotic material given the project is really engineered with new material.
Now go be creative and enjoy.
EDM is not necessary, but why not if it is available?
Nock your self out with it then. Have fun with it.
I was writing what I wrote coming from the point if view for someone whom may not be familiar with the many skilled trades and the related tools and equipment associated with The ability to make a rifle action.
Is it Nock or knock? I guess I got your GOAT. EDM was mentioned and I couldn't understand why he couldn't use it if available. I realize that I'm short of your knowledge, just asking questions.
This post is 8 yrs old , I think he gave up on it or designed the current I phone !
I just recently browsed this thread.
I have designed and prototyped quite a few actions front and rear locking and what I understand of your project led me to some comments :
If you are making a simple model cloning the Remington, reducing every dimension if OK. But, if you want to build a shooting model, then, some dimensions cannot be simply scaled down.
For instance :
-Do you really think possible,on a .50 bolt diameter, to locate a worjking extractor, and also have en inside bolt bore big enough to accomodate a firing ipin of a sufficient diameter and its spring ?. Also, in such limited space, it will be difficult, if not impossible to accomodate a spring of sufficient energy for igniting a primer. Not to mention a too small firing pin diameter and mass.
- You intend to use a modified Rem shroud. Whithout entering into details, this idea looks impossible.
-You want to make a very short action. Considering the lenght of the cartridge you want to chamber, adding bolt lugs and receiver counter-lugs lenghts, and even making those shorter than safe, the bolt stroke will not be possible to be less than 3 inches. As a rule of thumb,, an action lenght is about twice the bolt stroke value. This valid for actions of the SA lenght but, in the case of a reduced action, it will be impossible to reduce the trigger lenght, nor very much the barrel shrank lenght.
Remington, whose designers usually know what they dio, have created the XP100 action for the cartridge you intend to use. Bolt stroke can probably be slightly reduced. Bolt diameter could perhaps be some 5/8 and total action lenght reduced accordingly, but not that much.
The op hasn't posted in 7 yrs .
I guess you could nock yourself out with a bow string,,,,,,, would that work?
Sorry, I did not noticed the dates. Thought it was a recent one.
No apology needed , I've learned to check dates after posting long after the op has moved on .
To get around a couple of issues mentioned, you could go with a "fat bolt" design a'la the Hall and new Nuevo actions.
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