DIY barrel rifling

This seems very interesting... Opinions?


using salt water, electricity and a 3D printed jig

DIY barrel rifling using salt water, electricity and a 3D printed jig - The Firearm Blog

 

Yeah it would work. A process like this is already being used by the OEMs.

 

Interesting idea but consider a couple aspects:

1. The area electrically eroded is not very smooth. This may smooth out with use but you would likely want to follow with some other machining process to improve the surface finish. Lacking that you would likely want to only shoot jacketed projectiles or it seems lead fouling could be a problem.

2. Most rifling has lands that project into the bore as opposed to grooves cut outward into the bore. This allows for good engagement with the bullet to spin it. The bore's base diameter is comparable to the bullet's diameter so force required to move the bullet is the friction plus force to deform the bullet where the rifling lands are (that expands the bullet a tiny bit creating a good gas seal with barrel). This electro-machined barrel won't have good engagement with the bullet and will leak gas around it unless the base diameter of the barrel is smaller than the bullet. If that is the case, then more deformation of the bullet will be required to create that engagement. That will require more force and energy to squeeze the bullet smaller and cause it to bulge into the rifling groove. Initial pressures in the chamber will be higher and the barrel, chamber, bolt and receiver will need to be able to accommodate those. I suppose enough of the barrel could be eroded away to make a more conventional shaped rifle. Two issues with that is the base diameter of the barrel is now that rough surface and probably a secondary machining operation (such as broaching) would be desired to fix that. If that process is capable of being employed from the git-go then just skip this electro machining step. Secondly, it seemed the electro-machinist who wrote the article had some difficulty in predictably controlling the amount of material removed. Presumably with experience this could be overcome.

With more development this may be a viable solution for very low volume needs (1 or 2 DIY units) but it seems a questionable process for higher production runs. Still quite interesting and creative.

Thanks for the link. This might be a process I can use in the shop for other things.

AT

 

Like @Airtime mentioned, it is interesting and I know a couple of big outfits use this type of process, but for now I'll just continue to repurpose old barrels and order new blanks-until I am the proud owner of a used rifling machine. A machinist friend thinks he may have one located in southern Mississippi.

 

There are places where you can get therapy for that, Dunerunner.

 

Interesting look. I would make a mandrel my self maybe using this process, and rifle my barrels the old fashioned way by cutting the rifling from a core. Cut Rifling is considered the most accurate method devised, and the rifles accuracy will be better as well. Now for that Old Pratt and Whitney Sine Bar Riffling Machine I have been wanting.

 

Same site has a few other rifling projects. The first link is a machine that was later updated in the second link.

DIY Barrel Rifling Tool - The Firearm Blog

DIY Barrel Rifling Tool 2.0 - The Firearm Blog