Crown Questions

[The Crisco Kid]

The OP mentions slugging the bore to get the proper ball diameter. That's not easy to determine if it's an odd number of lands and grooves. Also, I've never tried to slug a bore without the breech plug pulled. Can an over size ball be driven into the bore and then pulled with a ball puller? Sounds a lot easier to borrow a few different size balls and just try loading and shooting them.

 

[SDSmlf]

Can an over size ball be driven into the bore and then pulled with a ball puller?

Drop a short brass rod down the bore before driving the oversized ball in. Leave some space between the ball and rod, then use the rod as a slide hammer to remove the ball by pointing the muzzle up and down.

 

[M. De Land]

The OP mentions slugging the bore to get the proper ball diameter. That's not easy to determine if it's an odd number of lands and grooves. Also, I've never tried to slug a bore without the breech plug pulled. Can an over size ball be driven into the bore and then pulled with a ball puller? Sounds a lot easier to borrow a few different size balls and just try loading and shooting them.

I use Cerosafe casting metal that will make a poured slug to be measured 30 minutes after cooling for and exact groove diameter measurement using a Powley gauge for uneven groove count.

 

[The Crisco Kid]

Drop a short brass rod down the bore before driving the oversized ball in. Leave some space between the ball and rod, then use the rod as a slide hammer to remove the ball by pointing the muzzle up and down.

That's too easy! How come I never thought of it?

 

[#BPBReloadingFFL]

I use a ball grinding stone chucked in a drill motor with the speed limited @ slow. Heavy oil or light grease. A few seconds and done smooth ,even.

 

[Relic shooter]

The OP mentions slugging the bore to get the proper ball diameter. That's not easy to determine if it's an odd number of lands and grooves. Also, I've never tried to slug a bore without the breech plug pulled. Can an over size ball be driven into the bore and then pulled with a ball puller? Sounds a lot easier to borrow a few different size balls and just try loading and shooting them.

 

[Relic shooter]

How to slug bore without removing the breech;

This is the method I've used on all of my ML rifles & pistols to formulate correct ball diameter patch thickness.
Method works equally well to determine correct diameter for slug shooting MLs & cartridge firearms.
Drop a 4"-6" length of brass rod down the bore prior to driving the lead slug in, then rock the barrel back & forth until the rod drives the slug out.
Driving action of the brass rod also helps improve measurement accuracy of the lead slug.
Relic shooter

 

[IanH]

I have never before seen that sort of exterior muzzle treatment. I like it.
I'll bet it makes quickly centering a ball board easier.

I did that to make it easier to pour powder out of a measure without spilling. Not my idea, I saw another swamped barrel muzzle done that way and copied it.

 

[IanH]

Probably the most accurate crown that can be made is cut with a properly fitting down bore spud, hand driven muzzle cutting tool. This is because the down bore spud orientates the most accurate square to the bore axis cut possible.
I always use my lathe with a spider in a steady rest for octagon or round barrels but even this is not as accurate as the spud squared , hand cutter tool ,specifically designed for crown cutting . This tool orientates the muzzle cut to the actual bore run out of the specific barrel.

A good gunsmith, really good, will indicate the bore only in two places when crowning: at the muzzle and an inch or two back from the muzzle. It really doesn't matter what hooks, curves, and corkscrews occur before that, only the part immediately behind the crown.

However, in the REAL WORLD, just like you pointed out, it is far more accurate to just use a piloted lap than just about any other method. Quick and dirty.

 

[longcruise]

Here's a crown that I'm contemplating how to solve. If you look carefully you can see that it was cut with the barrel out of alignment with the tool. Probably with the barrel stationary.

I've smoothed and cleaned up quite a few crowns but never one that was off center like this one. I don't have a lathe, etc., as some do so what might be a good approach for this one. So far I'm liking @SDSmlf method with ball bearings but I'm open to all suggestions.

 

[The Crisco Kid]

How does it shoot? It is off center and the whole muzzle job looks a little rough but if it shoots ok you might not have to do anything.

 

[necchi]

So far I'm liking @SDSmlf method with ball bearings but I'm open to all suggestions.

There's nothing better, go for it. It's just that simple.
If your confused or unsure of any step,, send him a PM,, I'm sure he'll give you individual help.
It's basically hand lapping, it's been done by apprentice for centuries,, it's that easy .

 

[jd945043]

Guys I coned everything in my house when I got Joe Woods aka Flintsteel coning tools. My God what a Joy start a ball without a darned short starter. Now my Traditions Hawkin Woodsman is a able to get shot alot when I was ready to put the darned thing on GunBroker because it was a Bear to load and tore the poo out of patches. Cone them all boys and let God sort them out.

 

[longcruise]

How does it shoot? It is off center and the whole muzzle job looks a little rough but if it shoots ok you might not have to do anything.

Never been shot. It's part of a CVA kit that I haven't started yet.

 

[HSmithTX]

If you use a ball to try to fix that it won't get any better I don't think. Best bet is to file/turn it back to flat/square to the bore and start over. Starting from a square muzzle and using balls works fine, but it won't help the crooked cut.

In the modern high power long range game there is no such thing as a hand cut crown, the barrels are indicated in and the crown is cut on the lathe. It's a hundred dollar job around here if the barrel is off the receiver already, costs more if the barrel needs removed. Seems like a lot but takes nearly an hour to do perfect (less than .0002') once the barrel is in hand.

 

[64Springer]

Here's a crown that I'm contemplating how to solve. If you look carefully you can see that it was cut with the barrel out of alignment with the tool. Probably with the barrel stationary.

I've smoothed and cleaned up quite a few crowns but never one that was off center like this one. I don't have a lathe, etc., as some do so what might be a good approach for this one. So far I'm liking @SDSmlf method with ball bearings but I'm open to all suggestions.

View attachment 242013

Buy a crowning tool and bushing from Pacific Tool and Gage.

A ball bearing will follow the same lines you already have.

What you need is a cutter that's concentric with the bore.

 

[Steve Wagner]

So maybe I'm crazy...I purchased a used TC Hawken w a pretty pitted muzzle and bore. Wouldn't shoot anything accurately so nothing to lose really. I read up on coning and made my own tool out of about 30 inches of tapered, graphite golf club shaft. The taper looked about perfect from pictures I saw. Created a 50 cal bushing out of masking tape for the front end to keep it centered. Then I added 2 sided tape in the area where shaft met muzzle and applied metal cutting paper starting at 200 and going to 600. I also worked over the entire bore with a fine valve grinding compound. Bore looks great now, loads much easier and shoots big conicals very well. Round balls still stink but I have other rifles for them. Golf and ML. 2 ways to launch projectiles finally meet. Quit the golf years ago. Just had some old clubs laying around. Yep, probably crazy. SW

 

[longcruise]

Buy a crowning tool and bushing from Pacific Tool and Gage.

A ball bearing will follow the same lines you already have.

What you need is a cutter that's concentric with the bore.

Yes, that would be the cats meow. But a 100 bucks to correct a cva?? Naw!

OTOH, it could have other applications. I have homemade tools that work in a set of three different angles and have been very good in cleaning up crowns but might not work for correcting that angle.

Still cogitating. Pacific tool might get my order. Thanks for that pointer. I'd never heard of them before.

 

[Nav]

PTG is one of the most famously bad companies in the percision gun community for out of spec parts and extremely poor quality machining. I have seen ridiculous pictures and plenty of stories about “drop in” parts that require $200 more Gunsmithing before they fit. The pictures of their reflex plates for pistols are worse than if you eyeballed it on a drill press.
Though, it couldn’t be any worse than a home “cone” job.
I would buy elsewhere. It’s not even like they’re cheaper. They’re just awful.

Check out their three-rail, “DARPA”, super secret, 700 action machined by “real veterans” (rather than trained machinists) on the front page of their website.
That place is a joke.

 

[64Springer]

Yes, that would be the cats meow. But a 100 bucks to correct a cva?? Naw!

OTOH, it could have other applications. I have homemade tools that work in a set of three different angles and have been very good in cleaning up crowns but might not work for correcting that angle.

Still cogitating. Pacific tool might get my order. Thanks for that pointer. I'd never heard of them before.

You would have it for life.

You can use it on other caliber bores with just a twelve dollar bushing change.

You could even rent it out to forum members to help offset the cost.

But, yes, they are expensive.

Good luck with it.