Gunsmithing Inletting for DBM questions?

[BillyGoatMachine]

I always try to fix or improve my rifles myself if the project seems doable with my limited gun smithing skills. Please go easy on me if this seems like a stupid question or has been covered before. I have a Badger M5 DBM that I purchased for my 700 308. The inletting pattern definitely doesn't match up with the DBM. The pattern on the paper is shorter than the actual DBM as far as overall length and magwell length. Is this a misprint on Badger's part, or is there something I am missing? Also, what is the easiest way to remove the stock pillars in a rifle stock? I tried using a large punch, but they seem really solid in there and I don't want to crack my stock. I assume I'm going to have to drill them out? Here's a couple of pics of the inletting pattern. Thank in advance.

 

[2156SMK]

Re: Inletting for DBM questions?

It looks like the inletting pattern was printed with PDF scaling turned on.
Turn off scaling before printing it.

If the stock already has pillars in it, LEAVE THEM!
Just shorten them to 0.725" and 1.070" like the included badger pillars.

The best way to inlet is with a milling machine.
You will be able to cut right through those existing pillars...

 

[BillyGoatMachine]

Re: Inletting for DBM questions?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2156SMK</div><div class="ubbcode-body">It looks like the inletting pattern was printed with PDF scaling turned on.
Turn off scaling before printing it.

If the stock already has pillars in it, LEAVE THEM!
Just shorten them to 0.725" and 1.070" like the included badger pillars.

The best way to inlet is with a milling machine.
You will be able to cut right through those existing pillars... </div></div>

Thanks for the help Randall! That's exactly how the paper schematics came from Badger. I just copied the original to make a cutout. I'll try to print off their website the way you mentioned.

 

[roggom]

Re: Inletting for DBM questions?

If you do not have a milling machine, it is best to have it done professionally. The money you think you will save will be less than the depreciation value of the stock if you jack it up. Without a milling machine, that is exactly what you are going to do. If you do have one, good luck with your project.

 

[BillyGoatMachine]

Re: Inletting for DBM questions?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: roggom</div><div class="ubbcode-body">If you do not have a milling machine, it is best to have it done professionally. The money you think you will save will be less than the depreciation value of the stock if you jack it up. Without a milling machine, that is exactly what you are going to do. If you do have one, good luck with your project. </div></div>

I do have one, thanks.

 

[LRI]

Re: Inletting for DBM questions?

Your best bet is to pitch the pdf drawing as its just an outline.

Get your calipers out and the radius gauges. Use the drawing as a profile and add your dimensions. Then figure your cutter offsets and whittle it out. With a manual its prolly easiest to figure a .025-.05 stepover along the tapers. Then you can smooth the scallops with a file afterward.

The biggest challenge will likely be getting the tangencies correct for the pair of arcs where the front of the box transitions to the nose for the front screw.

I asked over and over for a real print when initially drawing this up Badger isn't willing to disclose the dimensions to the end user.

 

[BillyGoatMachine]

Re: Inletting for DBM questions?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">Your best bet is to pitch the pdf drawing as its just an outline.

Get your calipers out and the radius gauges. Use the drawing as a profile and add your dimensions. Then figure your cutter offsets and whittle it out. With a manual its prolly easiest to figure a .025-.05 stepover along the tapers. Then you can smooth the scallops with a file afterward.

The biggest challenge will likely be getting the tangencies correct for the pair of arcs where the front of the box transitions to the nose for the front screw.

I asked over and over for a real print when initially drawing this up Badger isn't willing to disclose the dimensions to the end user.

</div></div>

Calipers it will be. Thanks for your input and advice. I did buy a cheap stock to practice on before tackling the real project. These projects are turning out to be really rewarding. I just glass bedded, and free floated the barrel on a stock Weatherby Vanguard I won at a NRA dinner. Shooting it yesterday rewarded me with a 1/2 moa improvement over stock.

 

[LRI]

Re: Inletting for DBM questions?

In the future, don't spend the sheckels for a stock.

4x4 fence post is a great material for proofing out a machine op when it comes to stock work. All your after is the general outline (pocket feature might be a better way to describe it) of the part. The draft angle on the stock really isn't important at this point. You can set that up when its time to inlet your stock.

Back when I did these on a manual what worked best for me was to literally write my own "CNC" (chad's numerical control) code out long hand. I'd get a legal tablet and just put numbers down in sequence. This way all I had to do was run the DRO to position and not have to do much mental work at the machine. Again, just make sure your tool radius offsets are done correctly. Do it incorrectly and you'll end up on the wrong side of the tool path and that means BONDO!

The biggest challenge is machining the outside radius portions of the inlet. Again, just figure your stepover to get a reasonably nice radius. The rest you can fudge with some emery or a file.

Good luck.

C.

 

[2156SMK]

Re: Inletting for DBM questions?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">Back when I did these on a manual what worked best for me was to literally write my own "CNC" (chad's numerical control) code out long hand. I'd get a legal tablet and just put numbers down in sequence. This way all I had to do was run the DRO to position and not have to do much mental work at the machine.</div></div>

I think I have the same thing on my yellow pad sheets, but I guess I would have to call it "RNC" right?
Oh what I would give to have a real cnc mill for this type of stuff...
I have been real close to building a small cnc router just for inletting.

 

[Gene Poole]

Re: Inletting for DBM questions?

Luckily you don't have that hunk of aluminum in your way that you get in an HS Precision stock. I had to buy 3 carbide burrs, but I managed it with a drill press and an X-Y mill vise and some finesse with a dremel (and a little devcon). In the end, It only cost me twice as much money and 5 times as much time to do it myself.