Unhappy with a home rifling experiment.

[pizzaman5000]

I tried button rifling a piece of 1045 steel I had lying around, it didn't turn out quite as clean or properly dimensioned as I'd hoped. I think perhaps the steel isn't too soft and sprung back too much. I'm going to find some 416 rod and try that. Anyone have experience with DIY button rifling 1045 steel? If I'm trying to make a barrel, what's the best steel to start with? 416, 4140… I don't have my heat treating setup together yet so preferably it would be a steel I would have to harden.

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[spookshack]

@Vernonia MW

 

[pizzaman5000]

I tried button rifling a piece of 1045 steel I had lying around, it didn't turn out quite as clean or properly dimensioned as I'd hoped. I think perhaps the steel isn't too soft and sprung back too much. I'm going to find some 416 rod and try that. Anyone have experience with DIY button rifling 1045 steel? If I'm trying to make a barrel, what's the best steel to start with? 416, 4140… I don't have my heat treating setup together yet so preferably it would be a steel I would have to harden.

View attachment 2237709

I also think I could use more lube or different lube, and maybe I was pushing the button the wrong way. It seems like one end of the button has a larger OD, and I had that behind the cutting grooves. Maybe it's supposed to go first. I'll cut another blank and go again. Maybe try hammering the button through instead of pressing it.

 

[VinnieBoomBah]

Kind of hard to say how successful your experiment was without knowing all the parameters, mostly what are you using for a hammer and how does that compare to commercial hammer forging equipment. Truth is your experiment could have been phenomenally successful given what you are working with

 

[Vernonia MW]

Full disclosure, I do not have any experience rifling. Just a lot of tangential knowledge.

Do you have a picture of the button you used? Some of the pictures I've seen, they are rather crudely made.

What were you using as a lubricant?

Generally speaking, all steels have a similar modulus of elasticity. Meaning regardless of alloy or heat treatment, the amount of "spring back" you get will be about the same. I would recommend trying a chunk of pre-hard 4140. Despite the name, it is still relatively soft (30 HRC or so). It is readily available, cheap, and is commonly used for gun barrels. It is best to heat treat your steel before machining the bore/rifling. If you do so afterwards, your barrel will likely warp.

 

[Rkangel]

I'm absolutely no expert by any means, but what about pulling the button instead of pushing?

I may be wrong but it seems from what I see online many barrel companies braze the button to a rod and pull it through the blank.

 

[pizzaman5000]

Full disclosure, I do not have any experience rifling. Just a lot of tangential knowledge.

Do you have a picture of the button you used? Some of the pictures I've seen, they are rather crudely made.

What were you using as a lubricant?

Generally speaking, all steels have a similar modulus of elasticity. Meaning regardless of alloy or heat treatment, the amount of "spring back" you get will be about the same. I would recommend trying a chunk of pre-hard 4140. Despite the name, it is still relatively soft (30 HRC or so). It is readily available, cheap, and is commonly used for gun barrels. It is best to heat treat your steel before machining the bore/rifling. If you do so afterwards, your barrel will likely warp.

I got it from https://hammerbutton.com/

I used a press and cut a transfer punch to use in short segments to push it through. I'm making a 9mm Makarov barrel for a cz82. I don't know a great way to measure the lands and grooves, I have calipers and micrometers, but not ID measuring tools. I'll make some attempts at measuring tonight. The lands just don't look nice, and they look way too shallow.

Heres my button:

 

[pizzaman5000]

My process was: cut a 6" section of 1.24" ground and polished 1045 steel I had from a previous project. Drill through it using an 11/32 bit on my lathe, then ream to 9mm on the lathe. Then I shoved this button through with a press, skinniest side first. I was hoping to not need to heat treat at all, I'm not terribly worried about barrel life at this stage, more just practicing getting rifling and dimensions right. Maybe I need to heat treat first though. I also haven't done any hardness testing, so I'm not sure where my 1045 steel is on the Rockwell C.

Edit: I used air tool oil as lube. Probably not thin enough, maybe tap cutting fluid is better.

 

[Vernonia MW]

Hard to tell from the pic, but your rifling looks to have some galling going on. Going to a harder steel could help with this. The picture of your button doesn't make it look horrible. I do feel that the rub marks shouldn't be there after one use, though that is just conjecture.

You can purchase some full ball bore gauges for relatively cheap that will allow you to get a more precise measurement of the diameter. They can be a bit finicky, though.

I would recommend a high pressure grease for lubrication.

 

[Mark W.]

If your cutting use a cutting fluid

 

[pizzaman5000]

Hard to tell from the pic, but your rifling looks to have some galling going on. Going to a harder steel could help with this. The picture of your button doesn't make it look horrible. I do feel that the rub marks shouldn't be there after one use, though that is just conjecture.

You can purchase some full ball bore gauges for relatively cheap that will allow you to get a more precise measurement of the diameter. They can be a bit finicky, though.

I would recommend a high pressure grease for lubrication.

Thanks, I will keep at it. The button was only $65 shipped, not a bad deal at all. Claims to be 80-90 HRC, but I don't have reliable hardness testing.

 

[Vernonia MW]

Thanks, I will keep at it. The button was only $65 shipped, not a bad deal at all. Claims to be 80-90 HRC, but I don't have reliable hardness testing.

If you are getting galling, then the parent material is welding itself to the tool and then breaking off. It will take parts of the carbide with it. Same thing happens with built up edge (BUE) when using a cutting tool.

Again, I am not someone who's rifled a barrel, but I am willing to bet your lubrication is the primary culprit. A high sulfur cutting oil, or a high pressure greasd is where I would tend to gravitate towards. It sounds like you have the opposite theory. Maybe try a thinner oil like you want, and then try something thickee. And please keep us posted with the results! I would love to try what you are doing some day.

 

[pizzaman5000]

If you are getting galling, then the parent material is welding itself to the tool and then breaking off. It will take parts of the carbide with it. Same thing happens with built up edge (BUE) when using a cutting tool.

Again, I am not someone who's rifled a barrel, but I am willing to bet your lubrication is the primary culprit. A high sulfur cutting oil, or a high pressure greasd is where I would tend to gravitate towards. It sounds like you have the opposite theory. Maybe try a thinner oil like you want, and then try something thickee. And please keep us posted with the results! I would love to try what you are doing some day.

I have an old can of sulphur base cutting oil, I'll switch to that. I don't know what I'm doing at all, so I'll go with your theory first haha. I just watched Serbu's DIY rifling videos on YT, and I have a mechanical engineering degree but I went the HVAC route so all my machining and properties of materials stuff went the way of long division.

 

[Omni]

I don't know a great way to measure the lands and grooves, I have calipers and micrometers, but not ID measuring tools. I'll make some attempts at measuring tonight.

You can hammer a tight fitting piece of pure/soft lead, like a fishing weight or muzzle-loader ball down the barrel to get an accurate groove diameter measurement.

 

[pizzaman5000]

You can hammer a tight fitting piece of pure/soft lead, like a fishing weight or muzzle-loader ball down the barrel to get an accurate groove

Smart man.

I took a virgin 9mm mak bullet and pushed it through. It's a 4 groove, and the lands and grooves that are 90 degrees from each other are not dead symmetrical. I'll call the largest measurement the 'A' diameter and the smaller measurement the 'B' diameter.

Measuring the 'A' lands(bore) I get 0.375" and 'B' lands are .374". Best I can tell the 'A' groove diameter is 0.357" and the 'B' groove diameter is 0.3525".

9mm = 0.354331, 9.4mm = 0.370079. I'm not too far off.

I am not supremely confident in my measurements, all my micrometers are from garage sales and marketplace but I took dial caliper measurements and use two different 1" micrometers and they were all agreeable-ish, within a thou.

I'm tempted to turn the OD down to the right size, ream out the chamber, and swap it into my cz82. I can also shove a few virgin bullets through my current cz82 barrel and compare the results. I'm starting to think this may function. Not a quality bore by any means, but maybe a functional(and not dangerous) one.

What do you guys think? 80/20 I can hit a pop can from 10 yards with this thing?

 

[pizzaman5000]

Barrel update, I've reamed the chamber, and taken the OD down to 0.550". I believe the chamber will have a finished OD of 0.510" for the section that is pressed into the frame, and the rest 0.5"

I'll make sure to measure the factory barrel of the pistol when I figure out how to press it out just to make sure before turning the rest down. I'm also leaving a little meat on the chamber end so that I can make the slot for the ejector and fiddle around with a carbide burr to get the feed ramp right. Might spring for some GO/NO GO gauges, might not.

Getting closer though, and I don't feel so bad about the rifling anymore after investigating the rifling on the barrel that is already installed in the pistol.

Pic note: The extra barrel at the top is a vz61 barrel I mistakenly thought would be long enough to thread and swap in. Slightly different chamber and not really any longer.

 

[gmerkt]

Very ambitious. Here is one listed on ebay for $50:

CZ 82, 9 x 18mm Pistol Parts: Barrel & Recoil Spring | eBay

We do not know if parts are interchangeable. It is always best to only buy parts that are specifically for your gun. No uppers or lowers. No kits to build a firearm.

www.ebay.com

 

[pizzaman5000]

Very ambitious. Here is one listed on ebay for $50:

CZ 82, 9 x 18mm Pistol Parts: Barrel & Recoil Spring | eBay

We do not know if parts are interchangeable. It is always best to only buy parts that are specifically for your gun. No uppers or lowers. No kits to build a firearm.

www.ebay.com

Not long enough to thread though

 

[pizzaman5000]

Alright, latest update, figured out how to press the barrel of a cz82 out. The retaining pin is a horrific bubblegum, I ended up grinding my one "made in USA" punch down to get it out. 3lb hammer. Once the pin was out, I ground down a cheap transfer punch I had that was just smaller than the chamber hoop on the frame and used heat, pb blaster, and my little brass hammer while gingerly applying pressure with the press. Barrel is out, looks like my OD for the press fit part needs to be .5057".

 

[pizzaman5000]

I think the right sequence of operations now is to turn my homemade barrel down to the right dimensions, and then press it in. Then cut the ejector slot with the mill using the ejector slot on the frame as a guide and then use a die grinder or dremel with a carbide burr to shape the feed ramp. Once the barrel is in and the ejector slot is carved I can drill the pin slot and knock that sucker back in.