Just collecting info - R700

[macardoso]

Hi all,

I am getting close on finishing up a few long term project in the coming months and wanted to readdress a project I have wanted to do for a long time.

I am not a huge gun enthusiast, nor do I hunt, but I do have a serious appreciation for the engineering and mechanical design that goes into firearms. I have considered scratch building a Remington 700 and I'd like to address that idea again as a potential next project.

I don't really have a whole lot of interest in building one unless I am going to make every single part from scratch (action, both, stock, trigger group, magazine, etc.). The only allowance I'd be willing to take is purchasing a barrel blank that has been rifled already. I have a few questions which I hope someone might be able to point me in the right direction.

1. On a scale of 1-10, how difficult does this sound? I am no stranger to taking on difficult long-term projects, but I mostly do electromechanical stuff (like my robot or CNC). I am building a steam engine and having a lot of fun with it - this seems like a logical progression.
2. Where would I find drawings or specifications for the components? I could always buy a rifle to copy from, but I would be missing information like material specifications and tolerances.
3. Are there any components that are unreasonable to produce at home?
4. Can stock material be purchased pre-hard or would I need to actually get involved with a heat treat company.
5. What kind of cost would be associated? I know chamber reamers can be very expensive.
6. What kind of specialty tooling would be required?
7. I have a 12x36" lathe and a CNC G0704 with a 4th axis. Would this be sufficient to make all the parts? Is precision grinding required?
8. Are there any legal considerations? I would be making it with a full length barrel and for personal use only.
9. Is there any reason I couldn't build a moderately accurate rifle at home?

Thanks so much. I'm really not part of the firearms community, so there is a big risk of "I don't know what I don't know".

-Mike

 

[pontiac428]

I love the Rem 700, it is my favorite. I own seven of them, and do my own work. I've never made one from scratch. For the receiver, he bolt raceway can be cut by EDM into the receiver blank and the rest of the machining can be done on a mill and lathe. I've read discussions about the prospect of doing the bolt hole in the receiver with a shaper, but haven't seen it done. There have been one or two home shop types in the past who offered a receiver with a pre-cut bolt raceway (EDM process), but those are long gone. This is the biggest challenge for making these rifles. Buying (rifled) a barrel blank is the way to go. A $200 BBL is a lot cheaper than buying tens or hundreds of thousands of dollars worth of button rifling equipment for the sake of making your own. Trigger components are made with EDM these days, but you can grind the parts just as well. Drawings are all over the web, but the BEST thing to do is take apart a Rem 700 and measure it yourself. Heat treat can be done in the home shop, read up on it. No need to pay for a certified heat treat job. Costs will depend on what you have for tooling. Most of the operations on the rifle are traditional machining ops, so your tooling stock-on-hand will determine the total price. I don't think the cost of a chamber reamer is worth worrying about, in other words, keep a few hundred bucks on reserve for supplies. I don't expect this to be an economically profitable endeavor, you're probably going to pay several times the rifle's price to do this exercise. Your lathe is good enough and the CNC will come in handy for completion. Legally, you may build your own rifles as long as they are not otherwise illegal (your citizenship status, machine guns, sawed-off shotguns, stuff like that). Your rifle will not be transferable to another individual until you "import" the rifle on an ATF Form 4. That is your only route to a serial number, but it is cheap and quick. As long as the original builder is in possession of the firearm, it is lawful to have a home-built gun with no serial number on it.

You don't need to worry about the firearms community, I'm not a part of it either. I am an enthusiast that likes machining more than I like guns and politics. This is a fine place to ask questions because we are politics-free and interested in the craft first and foremost. There are also several seasoned gunsmiths and enthusiasts on this site who enjoy chucking a rifle into their lathes that can help answer questions.

 

[walz10]

I have also contemplated building a rifle from scratch. More like a receiver, stock and bolt in my case. I don’t have any interest in making a trigger group or ever rifling a barrel. I wasn’t thinking that I’d copy any one particular design completely but more along the lines of taking the bits I like from a bunch of different guns. Like a 700 style firing pin with a different style ejector. I also like how a Savage has a jam nut on the barrel and a bolt on bolt handle. I’ve been pondering how I’d lock the bolt for a while and haven’t come up with anything I like yet. The moral of the story here is yes you could do it in your home shop with the machines you have now. You could save yourself a ton of time buying a few parts here and there in my opinion. Do what makes you happy though. I personally don’t have the patience for a project that spans more than a few months. When I’ve attempted those in the past they’ve just ended up as a pile of parts that collected dust until becoming scrap or morphed into another project.


Sent from my iPhone using Tapatalk

 

[silverhawk]

The receiver can be made without EDM, but if you go this route, you will be creating a custom broach and broach guide. Once those lug lock channels are cut, the rest should be machinable. For the consumables like triggers and springs, u would simply buy them.

As said previously, you might need an existing 700 you can take a part to use as your blueprint. When you do, you will note why the previous respondants talk a lot about the EDM on that.

My question in response to this is... what materials would others suggest? What are your personal plans on materials?

joe

 

[macardoso]

For the receiver, he bolt raceway can be cut by EDM into the receiver blank and the rest of the machining can be done on a mill and lathe. I've read discussions about the prospect of doing the bolt hole in the receiver with a shaper, but haven't seen it done. There have been one or two home shop types in the past who offered a receiver with a pre-cut bolt raceway (EDM process), but those are long gone. This is the biggest challenge for making these rifles.

I have seen a guy selling short and long action EDM blanks on Practical Machinist. His last post was in 2015 so I question if he would still offer them. I know this one operation is probably the most difficult of the entire build. I also considered using the lathe as a shaper or broach with a guide bushing to support the cut. Fortunately it is also the first operation that needs to be done - more or less.

Buying (rifled) a barrel blank is the way to go. A $200 BBL is a lot cheaper than buying tens or hundreds of thousands of dollars worth of button rifling equipment for the sake of making your own.

100% agreed. I couldn't do a good job anyways and this wouldn't feel too much like cheating the process.

Trigger components are made with EDM these days, but you can grind the parts just as well.

Gotcha. So definitely more precision than CNC and files. Could probably use fine India stones by hand for fit. I'd probably buy a trigger to start and work on copying it to my own build.

Drawings are all over the web, but the BEST thing to do is take apart a Rem 700 and measure it yourself.

I figured

Heat treat can be done in the home shop, read up on it. No need to pay for a certified heat treat job.

That scares me a bit but it does seem reasonable to do.

Costs will depend on what you have for tooling. Most of the operations on the rifle are traditional machining ops, so your tooling stock-on-hand will determine the total price. I don't think the cost of a chamber reamer is worth worrying about, in other words, keep a few hundred bucks on reserve for supplies. I don't expect this to be an economically profitable endeavor, you're probably going to pay several times the rifle's price to do this exercise.

I have no misconceptions about this not being the most economical to own a gun. I'd be doing this purely for the challenge and the pride in finishing it. I have a well stocked shop for general machining and measurement. I'd have to build some specific tooling to do this.

Legally, you may build your own rifles as long as they are not otherwise illegal (your citizenship status, machine guns, sawed-off shotguns, stuff like that). Your rifle will not be transferable to another individual until you "import" the rifle on an ATF Form 4. That is your only route to a serial number, but it is cheap and quick. As long as the original builder is in possession of the firearm, it is lawful to have a home-built gun with no serial number on it.

OK cool. That was my understanding as well. What does importing the rifle do exactly other than issuing you the serial number?

You don't need to worry about the firearms community, I'm not a part of it either. I am an enthusiast that likes machining more than I like guns and politics. This is a fine place to ask questions because we are politics-free and interested in the craft first and foremost. There are also several seasoned gunsmiths and enthusiasts on this site who enjoy chucking a rifle into their lathes that can help answer questions.

Awesome, I appreciate that. I too am only interested in the craft and have little interest in many of the other discussions on those sites.

 

[macardoso]

I have also contemplated building a rifle from scratch. More like a receiver, stock and bolt in my case. I don’t have any interest in making a trigger group or ever rifling a barrel. I wasn’t thinking that I’d copy any one particular design completely but more along the lines of taking the bits I like from a bunch of different guns. Like a 700 style firing pin with a different style ejector. I also like how a Savage has a jam nut on the barrel and a bolt on bolt handle. I’ve been pondering how I’d lock the bolt for a while and haven’t come up with anything I like yet. The moral of the story here is yes you could do it in your home shop with the machines you have now. You could save yourself a ton of time buying a few parts here and there in my opinion. Do what makes you happy though. I personally don’t have the patience for a project that spans more than a few months. When I’ve attempted those in the past they’ve just ended up as a pile of parts that collected dust until becoming scrap or morphed into another project.

I'd love to do this as well but I figured this was a good place to start learning the craft. I have sketches of a design for a gas fed rotating bolt mechanism with a delayed ejection of the cartridge. I'd love to get enough experience to design it for real and build it.

 

[macardoso]

The receiver can be made without EDM, but if you go this route, you will be creating a custom broach and broach guide. Once those lug lock channels are cut, the rest should be machinable. For the consumables like triggers and springs, u would simply buy them.

As said previously, you might need an existing 700 you can take a part to use as your blueprint. When you do, you will note why the previous respondants talk a lot about the EDM on that.

My question in response to this is... what materials would others suggest? What are your personal plans on materials?

Joe, thanks much for the response! I am very familiar with the issues that come about as a part of the raceways in the receiver. I would probably buy a trigger but also try my hand at building one because it sounds fun!

I expect that I'd need a rifle to reference, but I was curious if anyone had production prints, much like the steam engine I am working on now. I figured there wouldn't be, but wanted to ask. I do have a buddy with access to a wire EDM if I get really stuck. Unfortunately it is too small to do the lugs on the receiver.

I'd probably aim to make it from 17-4 PH or something along those lines.

 

[silverhawk]

If someone here has the production prints for a 700, I would be interested to see them, too.

joe

 

[shooter123456]

Your rifle will not be transferable to another individual until you "import" the rifle on an ATF Form 4. That is your only route to a serial number, but it is cheap and quick.

What does importing the rifle do exactly other than issuing you the serial number?

This isn't accurate. A Form 4 is used for transferring an NFA item (Short barreled rifle, suppressor, machine gun, etc). A Form 4 would not be used to transfer a non-NFA item. That would be a 4473 if done through a dealer, but there is no federal requirement that a person to person sale go through a dealer with 4473. Some states do require it however. As for "Importing", an individual can't import a firearm. You would need to get an FFL to do that, and as far as I am aware, the ATF is no longer issuing FFLs to home dealers.

If you wanted to sell it, you could can assign your own serial however you see fit and engrave it. There is actually question about whether a serial number would even be required for a homemade rifle, as the law requiring a serial number very specifically mentions "Manufacturers" and the ATF is very clear that someone making a homemade firearm is not a manufacturer.

If you are curious, look up the rules for 80% lowers as legally a scratch built gun is treated the same as a completed 80% lower.

 

[macardoso]

Sent an email to one of the guys offering action blanks with EDM'd raceways. Let's see if I get a response