Falling Block Rifle Book

O.K. I have some skills in machining, and I was wondering how do I cut a rectangular slot in a rifle frame, such as Walter B. Meuler's Falling Block Rifle or anthing else, for that matter?

Well, Mueller used a shaper. Outside of that there are broaches ($pendy for home use) and files. (labor intensive) You can make a broach at home from drill rod and harden it. A lathe bit can be ground into a scraper that can be used in the mill ram, again labor intensive. Lastly there's EDM - a couple of quick and dirty EDM plans are available for the hobbiest. It's a tough task for a hobby guy without a vast shop.

Thanks, What is a Shaper? And were can I buy one?

Ahhh, a shaper is a tool that is considered obsolete in most modern shops. It has a ram that travels back and forth and uses a bit much like a lathe toolbit to scrape metal off of a surface. In the home shop a shaper is great for cutting square holes, keyways, splines, and gears (especially internal). I've posted a pic of my Atlas 7" (The 7" denotes the longest working stroke the shaper can take.) Finding one will vary depending on you location. Ebay has them frequently and they go for $500 - $1000 depending on condition and location. (West coast fetchs more.) Shipping will run you another $200 or so.Shaper A web search will turn up more info for you.



[This message has been edited by GeneT (edited 11-07-2002).]

Sweet! Neat Pic thanks. I thought of an idea that probally won't work, but what if I made the reciver 2 pieces? Like, taking the
frame and "cutting" it in half? So use 2 pieces of block steel and then screw them together? Could this work????????
Thanks

Are you thinking about making the receiver in two pieces - a right and left side? The breech block mortise would be formed by cutting a notch in each side? The halves could be screwed or brazed together. This would work with a low powered cartridge like .22rf. Many .22 single shots had built up receivers. I'd be more than a bit nervous about using this construction with more powerful cartridges. If you want to make a .22 rifle, deHaas' Chicopee designs would be a good starting point.

Yikes! As Dick noted, that would be OK for a .22, but I'd steer clear of that for centerfire cartridges. (Whenever making a rifle from scratch I always test it by pulling the trigger with a string from behind safe cover. I neglected one other possibility - chisels. There are some nice diamond point chisels with which an able body can rough in a corner, then file to fit. Both efforts will require patience and care, but those are always the most satisfying endeavors. Stay safe, and good luck!

I just thought of a viable solution to this problem imo which could be applied when machining the square corners of the mag well on an AR-15 receiver or similar slots.

The falling block action will need to be made a little bit wider to keep the strength the same.Rough out the majority of your dimensions of your rectangular slot.Then use a long 3/16" or 1/4" endmill to clean up your corners and machine to your final dimensions.The corners will have a radius which will be less likely to crack.


Then add the appropriate thickness 3/16" or 1/4" hardened and ground flat stock to the two sides(left and right of action) of your rectangular slot.Two screws loctited to hold the flat stock in position should be sufficient as there shouldn't be any force on the flat stock.You might try low temp silver soldering the flat stock if you don't need to heat treat your action after machining.

For test firing try laying the rifle with the butt inside an old tire.Lay sand bags across the action and barrel to hold it down and prevent any shrapnel in case it blows up.Fire one shell at a time at a safe distance with a string to pull the trigger.

Note any signs of incorrect headspace,high pressure,firing pin length,case separation,cracked necks,primer leakage or puncture,brass flow,primer pocket enlarging,primer flow into the primer pocket,offset firing pin strike,depth of firing pin strike,lengthening case,case dimensions before and after firing.

Keep notes and stop if anything looks questionable.You only have one head,think safety.Read all the gunsmithing books that you can and start with a 22LR as it would be more forgiving if something goes wrong.

Even a 22LR makes a horrible noise when a case separates.I had an old worn out Remington 510 bolt action have a case separation.I couldn't hear for a couple of minutes afterwards and I had a lot of background ringing for a few hours.My glasses had a piece of molten brass lodged in one lense and I had to pick a few slivers of brass out of my trigger hand.

Be Careful!!!!!!



[This message has been edited by Barry Briscoe (edited 11-08-2002).]

My Idea sounds a bit scary so I will not attempt! I suppose I could chisel, and file the edges square inside of the block (thanks GeneT), and then buy a slighty bigger breech block and fit the breech block to the size of the slot?

A few years ago,I saw an antique black powder cartridge rifle which was hand made. It vaguely resembled a Winchester 1885; drop block boxlock. The receiver had been whittled out of a solid block. I presume that the mortise for the block had been cut by drilling/chiselling/filing. Interestingly, a muzzleloading barrel had been used. The chamber was cut to accept a .40-60 case shortened until the bullet would fit both the barrel and the case. The rifle was well made, but it gave the impression that it had not been made by a gunsmith - just the styling details.

use stress problems in the heat treating process.I know that stress relieving cuts can be machined in the corners.Will matching the radius by hand be impossible?I know the old time makers did a lot of seemingly impossible jobs without the cutters and machinery we have access to today---TS

my reply was cut off in the middle. I asked if leaving the reciever cavity with a radius and shaping the falling block to fit the radius is practicle. It would also serve as stress relievers to prevent cracking during the heat treating.Can the radii be done by hand accuratly enough----TS

I can't say for sure if it would work but I don't see why not. I was going to do it that way. Use a standard size radius and get a radius cutter for the block. It should be easy to do on the mill being outside surfaces. For the inside why not plunge cut with a long endmill? or a round file the size to match the radius? If I remember correctly it is a through and through channel.

You should have a slightly larger radius on the block than in the receiver so there is no contact on the radii. All contact that resists the cartridge firing pressure should be at the back of the receiver mortise.

A local Wire EDM shop quoted a shop rate of $65 an hour. Considering he can cut three action blocks in an hour, its not too bad of a cost. Just be sure and give him a good print of what you want (tolerances and surface finish, etc). Plus drill a hole in the metal so they can run the wire through.
Hope this helps. Larry

AZ MACHINIST,I would like info on theEDM shop that you [email protected]-------I have a source on the East coast area but AZ is closer and would like to talk to them.----TS

Hello Tim,
Sorry for the delay in responding. I emailed you the info on the edm shop here in Arizona.
Hope it is of help.
Larry

Larry I may be repeating myself.It turns out that my new neighbor across the street has a business making barrels for the chain gun. He EDMed the slot for my Mueller action.Nuts on and smooth hole no finishing needed. I eliminated the automatic saftey and made a trigger block safety got away from a lot of complicated work insise the falling block.Coming along nicely,The neighbor turned me on to a friend Bo Clerke who makes super barrels and a lot of good info on making a rifle------TS

Hey,
If you don't have room for a shaper, and you already have a milling machine, then you might consider a shaping head for the back of the ram on most Bridgeport's and clones. That is what that hole is for(that and a cherrying head)
David from Jax

In the book on Walter Mueller's action he describes how to do it with out a shaper.