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Stangs55

Private
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Full Member
Minuteman
Jan 26, 2010
142
62
Texas
So I've wanted an excuse to buy a 3D printer for a while simply to make this. Finally took the plunge and picked one up. Coming into this, I knew zero about CAD design or 3D printing...so it's been alot of YouTube but I finally made a thing. Be gentle...I had no idea what I was doing and had to teach myself.

This is a replacement for the black insert that comes with the MTM H50-XL Deluxe Ammo Box ( https://mtmcase-gard.com/products/deluxe-ammo-box-50-round-handle-300-wsm-300-rem-ultra-mag ).

It is designed to more securely hold loaded 300 PRC ammo for transport. The insert that comes with the box holds the ammo near the bullet tip. I've never liked this design...especially as someone who often flies with loaded reloads. Ammo often arrives having banged around in the case. I've even seen this change my COAL and (I would assume) concentricity of loaded rounds. So this was designed to hold the body tighter and index off the shoulder and not the bullet. The bullet floats freely with the only "pressure" being on the shoulder of the case. In addition, I also increased the height of the insert to securely hold more of the body of the case. In theory, I feel this should be a better solution.

The cartridge cuts for the case were made from SAAMI spec 300 PRC dimensions. The COAL should be plenty long for 99.9% of 300 PRC reloads, even those that go beyond standard mag length. Of course this will also work for similar cartridges beyond the 300 PRC, but YMMV depending on what you use.

So why not design a whole new ammo box with this integrated? Well that was my original intent, but I like this solution better. I don't think you're going to print a more secure or better box than the injection molded plastic that MTM makes. I think this is the best of both worlds.

Next step will be making more insert for my other cartridges I commonly travel with.

You can download it here if you want to give it a try: https://www.thingiverse.com/thing:5810858
 

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Love what you did there. Take a look at the very affordable Apache boxes from harbor freight. My guess is if you made a drop in insert for those you could make a killing. And if your printer won’t accommodate the size do like a modular thing with some type of dovetail to lock multiple pieces together. Would be cool cause you could then configure one case to hold different calibers
 
Since you have freedom of form factor try and print trays that lay horizontal.

F-class John did a few tests about traveling and now he uses “clam shell” holders to keep the ammo flat.

Look for it on YouTube, was really informative

Looks great 👍
 
Nice work! I’ve done similar with the tiny Apache 1800 (my girlfriend thinks it’s cute). The MTMs are nicer though. You can fit 112 308, 135 Grendel, and around 170 223 in the small case…still working on the 223. That thing looks beefy. I went a little lighter, with an upper tray to hold the base and a lower to reference the neck/shoulder to be configurable and adjustable for case length and neck size.
 

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Nice work! I’ve done similar with the tiny Apache 1800 (my girlfriend thinks it’s cute). The MTMs are nicer though. You can fit 112 308, 135 Grendel, and around 170 223 in the small case…still working on the 223. That thing looks beefy. I went a little lighter, with an upper tray to hold the base and a lower to reference the neck/shoulder to be configurable and adjustable for case length and neck size.
Do you have a STL file for this? I want to do one for 6.5 PRC and don't even know where to start.
 
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Do you have a STL file for this? I want to do one for 6.5 PRC and don't even know where to start.
I decided to tinker until I figured it out. Took me several hours but I have a pretty solid design for the Apache case from Harbor Freight. Working on printing one for 6.5 Creedmoor now. It’s a solid piece and uses a lot of filament but it’s sturdy and protects the tips really well.
 

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I decided to tinker until I figured it out. Took me several hours but I have a pretty solid design for the Apache case from Harbor Freight. Working on printing one for 6.5 Creedmoor now. It’s a solid piece and uses a lot of filament but it’s sturdy and protects the tips really well.
super cool. Do you have a file you can share. I just found out my public library has 3D printers for use. I would love to go give it a try
 
super cool. Do you have a file you can share. I just found out my public library has 3D printers for use. I would love to go give it a try
I’ll pm you. Just so you know, it’s about a 2 day print and uses roughly half a roll of filament. I’d hate for you to crank it up at the library and think the printer will whip it right up.
 
I’ll pm you. Just so you know, it’s about a 2 day print and uses roughly half a roll of filament. I’d hate for you to crank it up at the library and think the printer will whip it right up.
Haha damn… yes thank you for the heads up.
 
Printing in a public library, and taking it up for 2 days. Have at it !. What's the worst they do, say no ?
 
I’ll pm you. Just so you know, it’s about a 2 day print and uses roughly half a roll of filament. I’d hate for you to crank it up at the library and think the printer will whip it right up.
Nice work! I’ve done similar with the tiny Apache 1800 (my girlfriend thinks it’s cute). The MTMs are nicer though. You can fit 112 308, 135 Grendel, and around 170 223 in the small case…still working on the 223. That thing looks beefy. I went a little lighter, with an upper tray to hold the base and a lower to reference the neck/shoulder to be configurable and adjustable for case length and neck size.
Do you have a link to the file I’m interested in one for 308 and 6.5 creedmore
 
Do you have a link to the file I’m interested in one for 308 and 6.5 creedmore
Hey Brandon, I’m actually selling these now so I’m not really giving out the file. If you’re interested in one, pm me and I can get what you need printed for you. The link for the thread is below.