A fun holiday challenge

[LVLAaron]

Where does it specify the bottom metal it has to have???

I'm just the guy with the endmill. Folks are getting (possibly) mixed advice from the CMP on the unwritten rules.

 

[DR_2297]

Where does it specify the bottom metal it has to have???

If you scroll up I shared a conversation between myself and Brian Williams (CMP HP Coordinator) regarding bottom metal / magazine and him stating it was required because “original” rifles used it.

 

[DR_2297]

I am a Neanderthal doing mine. Bolt it down, scribe, remove, cut out middle with endmill and do find ends then swing my vise on swivel base until endmill follows the scribe line and then do one side then rotate other direction and repeat. Test fit and skim cut until if all fits. Finish up with chisels and scrapers if needed outside the mill

 

[6ShotsOr5?]

I needed to open up a bdl inlet to M5 on a couple of stocks. I cheated and wrote a program for Haas mini mill.

View attachment 1616785View attachment 1616786
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One of my best friends has a motto that he usually applies to danger scenarios, but it could apply to critical milling operations too -

“Always Cheat, Always Win.”

Also, using a programmable tool of any sort is not cheating if you can write the code!

 

[Kurz]

One of the first processes I chose for my CNC mill was I wrote programs for M5 inlets. Yes the rotary table works great for one or two inlets but more requires the automation of the CNC mill. I seem to run into the stocks I want but use the BDL inlet. Now I buy them and run the program on my mill.

Enjoy!

 

[LVLAaron]

I really need to take a fusion/cad course.

 

[AlNyhus]

If you scroll up I shared a conversation between myself and Brian Williams (CMP HP Coordinator) regarding bottom metal / magazine and him stating it was required because “original” rifles used it.

I saw that.

But there's nothing about that in the printed CMP rules posted here.

Let me get this straight. You can have a single shot 700, even though the originals were repeaters ? And you have to use BDL bottom metal even though single shot actions  are allowed?

 

[GenePoole]

I really need to take a fusion/cad course.

Anything but Fusion. Their cloud model means you are technically violating ITAR if you design gun parts. Also their licensing changes so often that you never know what features are going to suddenly require an extra fee.

 

[Alex Wheeler]

Sounds like a fun match. Id build one if there was a local match.

 

[LVLAaron]

I saw that.

But there's nothing about that in the printed CMP rules posted here.

Let me get this straight. You can have a single shot 700, even though the originals were repeaters ? And you have to use BDL bottom metal even though single shot actions  are allowed?

That’s our understanding. It’s also funny that you can use a brand new RAR action that’s been pillar bedded and blueprinted, but my 722 that’s actually from that era is illegal.

 

[DR_2297]

Sounds like a fun match. Id build one if there was a local match.

There are 4 categories in this match. WWII / Korea Semi Auto, WWII / Korea bolt gun, Vietnam era Semi Auto, Vietnam era Bolt gun. Lots of different rifles that can be used but some of the rules make no sense… like a model 70 HAS to be a pre-64 because that is what they USMC used in Nam before the M40 showed up.

A number of clubs around the country host CMP Vintage sniper matches but the big match is at Camp Perry during the national matches.

 

[xr650rRider]

The rules
https://thecmp.org/wp-content/uploads/2024/01/2024-CMP-Games-Rules.pdf

Page 62 has vintage sniper rifles definition.

 

[Infrequent Shooter]

best damn reading on the internet.

 

[X Count]

I really need to take a fusion/cad course.

I've got a subscription to Solidworks for makers. It's pretty well priced and I've used it at work. Most of what I've learnt is from YouTube.

Sooooo good for when your starting to bring multiple components together. You can manually measure, sketch and visualise things to an extent but in 3d can you can make a model and test to see how those things actually fit before you even order material.

Actually used it to mock up and M5 inlet. Once I had the model done I converted to a drawing and pinged all the dimensions using the back screw hole as the datum. Went to the manual mill and plunged all the corners and ends to the correct depths then went back and skewed the stock to the modelled angle to get the taper and cut between the plunged holes. You've done an awesome job without all the fuss so maybe not needed for you in this application but I kind of enjoy the process and having a number to work to.

Also handy for doing DXF files to use or send for profile cutting, stp files for 3D printing and just making decent hard copy drawings to have in the workshop.

 

[DR_2297]

I've got a subscription to Solidworks for makers. It's pretty well priced and I've used it at work. Most of what I've learnt is from YouTube.

Sooooo good for when your starting to bring multiple components together. You can manually measure, sketch and visualise things to an extent but in 3d can you can make a model and test to see how those things actually fit before you even order material.

Actually used it to mock up and M5 inlet. Once I had the model done I converted to a drawing and pinged all the dimensions using the back screw hole as the datum. Went to the manual mill and plunged all the corners and ends to the correct depths then went back and skewed the stock to the modelled angle to get the taper and cut between the plunged holes. You've done an awesome job without all the fuss so maybe not needed for you in this application but I kind of enjoy the process and having a number to work to.

Also handy for doing DXF files to use or send for profile cutting, stp files for 3D printing and just making decent hard copy drawings to have in the workshop.

Solidworks is the best software platform for 3D modeling where you don’t need powerful surfacing of PLM functionality.

Been using it since 2002, 7.5 of those years as my day job designing gauges, fixtures, tooling and machinery.

$24 / year for the makers license is the best bargain going at the moment.

 

[X Count]

I've only used autocad 2d so haven't used any other 3d to compare but others I've spoken to have said the same.

I don't have anywhere near your level of experience but it's been beneficial to learn and great for my applications.

Once you have some standard templates being able to "pack and go" the model, assembly and all the associated drawings and make modifications rather than start from scratch is a huge time saver. Having the drawing and assembly automatically update with just changing the model is very handy.

 

[LVLAaron]

I'll check out solidworks!

 

[GenePoole]

I'll check out solidworks!

I believe you've mentioned before that you are a fellow pilot. The Experimental Aircraft Association (EAA) used to provide a free student version of Solidworks. They've since switched to Siemens Sold Edge, but it is a "maker's" edition that is deliberately incompatible with their commercial version. At any rate, at $40/yr, an EAA membership may be the cheapest way to get into a professional CAD version.

I personally dumped Fusion when they removed the PDF export from their drawing workbench. That was the main thing I did with CAD: make drawings/prints of my work for the "customer".

I used FreeCAD for a long time because it was pretty much the only Linux option and now that I've dumped Microsoft completely, that is really the only option, but they have come a very long way since I first tried them out. The learning curve is a bit steeper than other CADs, but they have a very helpful community online.

 

[LVLAaron]

Good call on solid works. Pretty easy to figure out. I poked around for 20 minutes doing basic stuff. This would have taken me 4x as long in fusion.

 

[DR_2297]

The secret and power with Solidworks is that it is sketch based modeling.