Source for muzzle crown reamer

[longcruise]

I'm looking for a Muzzle crown reamer tool. Preferably a 60 degree but a 45 would work too. Any tips appreciated.

 

[deerstalkert]

i have used my chamfer tool for reloading for just about ever. finish the crown with my thumb and 600 grit wet/dry paper. it really doesn't take much.

 

[Larry (Omaha)]

I'm looking for a Muzzle crown reamer tool. Preferably a 60 degree but a 45 would work too. Any tips appreciated.

This is all I use. About any hardware.
Larry

 

[SDSmlf]

I'm looking for a Muzzle crown reamer tool. Preferably a 60 degree but a 45 would work too. Any tips appreciated.

Personally, I like to cut a 60° chamfer with a lathe, then polish. Without or without a lathe, I have used the ball bearing process I have posted about here a number of times to work muzzle.

Using a series of ball bearings (guess you could use glass balls or marbles), from about one and half times the bore diameter, to right around bore diameter, and using sandpaper of different grits from 120/180 up to 320 or finer (I take it up to 1000 grit
if I want a mirror finish, think working on someone else's gun). A couple of turns of the muzzle over each ball bearing with progressively finer sandpaper over them gives a smooth barrel crown to bore transition.

Basic idea is to hold the sandpaper over the ball bearing (you can place ball on the floor and hold paper with your feet, maybe on a pad or thin carpet if you don’t have a lathe to chuck up the barrel in) and rotate the barrel bore on the bearing with the sandpaper on it. Easy to keep barrel square with the floor. I’ll start with the larger diameter bearing and roughest grit paper and end with a smaller ball bearing near bore diameter, repeating with progressively finer grit sandpaper. I stop when I have a slight chamfer on bore and rifling lands that are highly polished.

I use Dykem (or a Sharpie) to mark the inside the bore so I can easily see when I starting to clean up everything without going too far. Note the 60° chamfer in the photograph was cut on a lathe, I just use the ball bearings to break up the lumps and sharp edges and polish the crown.

Note that with any method involving sandpaper, and your barrel is already finished, you are going to remove finish from the face of the bore if you don’t protect it. I’ve used ‘masking’ tape with a hole punched through it (use a wad punch), but only on other people’s gun’s, not worrying about the finish on mine.

 

[Grenadier1758]

@longcruise, many of us use the tool on our hand, the thumb. With a few sheets of wet/dry sandpaper of 320 to 600 grit. Some stop at 400 grit. Using the thumb to hold the paper at the crown, rotate the barrel back and forth about 1/4 turn 10 to 15 times. Rotate the barrel 90 degrees and repeat all the way around the muzzle.

The ball in the muzzle is good as it holds the sandpaper evenly at the crown. I would still rotate the barrel. I have started with the grinding ball as used by @Larry (Omaha).

I know the thumb isn't as precise as a specific chamfer tool used in a lathe, but most of us don't have access to a lathe of the size needed for crowning.

 

[longcruise]

@Grenadier1758 I have smoothed quite a few with my fingers and actually made three tools of graduated angles that work very well.

But, I have a barrel that must have been crowned at an angle such that the bevel is deeper on one side. My DIY tools don't quite work on this one. I think Ed Hambergs coning tool will complete the job and I'll be equipped to cone a couple other barrels. Sending a check off tomorrow.

 

[Grenadier1758]

Yep, @longcruise, the thumb works best when smoothing out a sharp crown. You need the tool when there is an angle at the crown.

 

[andy52]

Short of a lathe these tools do a very good job and you get any size pilot you want, the larger one shown is to square up the barrel after cutting and the smaller is for the crown the one that's in there is a .45

 

[ZUG]

Try "4D Reamer Rentals" - <https://4drentals.com/reamer-rentals/>

 

[wiscoaster]

I bought a set of the tools pictured above from Brownell's. They're extremely pricey, and I don't think they worked all that well, though it was my first attempt, so maybe that might be attributed to "operator" rather than to "tool".

I finished the job with a 45-degree grinding stone on a shaft in my drill.

I think the main problem with the hand reamer tool is that it doesn't deal well with lands and grooves in a rifled barrel. It would probably work just fine in a smoothbore.

 

[longcruise]

I looked at The rental reamers but they only went to 49 cal. I have an email off to 4d asking if the 49 pilot will work with a 50 cal. But since then I decided to get the coning tool.

 

[Eric Krewson]

I cut several crowns with a homemade hickory coning tool but the wood compresses after a couple of crowns and it doesn't work as well.

I have a couple of rifles with very tight bores that were hard to load, I decided to cone them to fix the loading problem. This takes away all the variables of cutting a less than perfect crown. I used a Joe Woods coning tool. After coning my rifles accuracy got better, probably because I didn't have to force a ball in so hard while loading. Thin patches to make loading easier turned to fluff in these rifles even after a complete bore polish.

After coning, I had cut the crown previously with my homemade tool; it did a nice job.

 

[PluggedNickel]

Short of a lathe these tools do a very good job and you get any size pilot you want, the larger one shown is to square up the barrel after cutting and the smaller is for the crown the one that's in there is a .45

View attachment 319304View attachment 319305

 

[bptactical]

Get what is known in the jewelry making world as “dapping punches”. They are essentially ball bearings welded to a punch body.
Chuck it in a drill and instead of sandpaper use lapping compound- it is more controllable than the sandpaper. Start wit 180 grit and progress to finer.
Use oil based compound such as Clover- the water based dries out too easily.

https://www.amazon.com/Dapping-Domi...af558304a9f736049e1883c1032cd617&gad_source=1

 

[PluggedNickel]

I have used these tools with good results for chamfering cylinder throats on revolvers as well. They work well by hand, you can also chuck them in a drill press if you have one.

 

[PluggedNickel]

They make this adapter for use in a drill press or hand drill as well.