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Posted: 3/8/2010 6:17:52 AM EDT
Finally going to get around to crowning my .223 barrel on my Savage 10FP. This one started as a sporter weight that I cut down. I tried the Brownells cutter, but just isn't working out, need to cut it in the lathe.

We have a small 8 by 30 Clausing with a 3 jaw and a steadyrest.
From what I've read, I should made a bushing with an ID taper for the barrel to ride in the steady. Do I need to find the 4 jaw for the chamber end, or will the 3 be good enough?

Just how close should the muzzle runout be? I know 0 would be ideal, but is there an acceptable range?

Probably have more questions, but I'll start here

thanks for the help guys
Link Posted: 3/8/2010 5:03:12 PM EDT
It would probably be more exact if you're able to lock the muzzle end of the barrel in a 4 jaw and the chamber/breech end of the barrel through the other side of the headstock in a 3 jaw.  Steady rests are nice, but they're not that precise.  As far as an acceptable amount of runout, as close to zero as possible, I realize that it might not be possible to get perfect zero, but about a half a thousandth or so runout isn't anything to get worked up about.
Link Posted: 3/8/2010 5:25:51 PM EDT
Depends on the 3 jaw. I have used shim stock between a part and one of the jaws on a three jaw, to get a part to run true, when a 4 jaw wasn't available.

Will you be checking the runout on the ID?

Instead of worrying about a steady and chucking the receiver. Can you get the barrel through the headstock, and use a Cat's paw to keep the receiver or barrel centered?

Where are you located?
Link Posted: 3/8/2010 5:42:15 PM EDT
If it were me and I could get the bbl through the headstock, I'd use a cat's head on the outside end and have as little overhang as possible on the chuck side. Use a gage pin in the bore to indicate for 0-0 runout, or maybe a half thousandth at most. Use brass/aluminum shim stock between the barrel and chuck jaws to keep from marring it up.

If you don't have a four jaw, it's pretty easy to make a cat's head from some heavy wall pipe and capscrews....just use brass shim stock between the screws and the barrel.
Link Posted: 3/8/2010 7:24:59 PM EDT
I'll have to check again, but I think the headstock was 20" and my barrel is 18". And there's no place to attach a cats paw either. Think I'm limited to the 3 or 4 jaw and steadyrest.

Can I indicate the bore directly, or should I turn a small gage spud to indicate?

Not too worried if it doesn't come out perfect, only paid $40, I can always redo it.

Gun Crank, I'm up in Hibbing. Shop is kinda lmited for odd jobs, setup for production of rock bits. But I do what I can.
Link Posted: 3/8/2010 7:47:58 PM EDT
I'd use a gauge pin like machinisttx recommended. If you were close I'd lend you mine. you could turn a spud. I wouldn't indicate off the OD.

I have turned long shafts without a catspaw. I made a light press fit plastic bushing that fit into the back of the headstock. I held .001 TIR on those parts.

I'd love to move up north. Don't know how busy I'd stay in the shop though.
Link Posted: 3/9/2010 4:40:32 AM EDT
The bushing idea may work out. I did manage to find the 4 jaw, cleaning it up now, think it has about 15 years of dust on it, no kidding

Found a spud I made before, nice snug slip to the bore, so I can indicate on that.

Looks like progress

I spent 7 years living in Coon Rapids/Blaine working in the EDM dept at Dynamic Engineering. Can't say I miss it too much, tho it was nice to have the Wires and Sinkers at my disposal
Link Posted: 3/9/2010 6:03:03 AM EDT
You can use masking tape on the end of the barrel inside the headstock, just keep wrapping it until you get a tight fit in the headstock, I've done it this way with great success, and seen it done this way many more times.
Link Posted: 3/9/2010 7:05:17 PM EDT
Well got it done, thanks for all the help guys

Used the tape trick, since the spindle bore seemed tapered and the breech end ended up in the middle somewhere. Had to cut a feeding ramp so it wouldn't keep jamming bullets .040 low of the chamber. Cut the feed cone first, setup for the crown second. Got it dialed in within .0002.
Looks good to me, here's some pics

Feed cone setup


Crown setup


Feedcone and crown



The Savage it's on, need to get her sighted in and whack some coyotes I've been hearing

Link Posted: 3/10/2010 6:53:24 PM EDT
Well, if you had been cutting an 11degree, or conventional rounded edge crown, all that precision would have been well worth taking.

Correct me if I'm wrong (always a possibility with me) but the picture looks like a recessed 90 degree crown. In which case, I think working to 2 "tenths" is overkill. A nice clean cut at 90 degrees is what's needed, concentricity is a minor consideration (IMO)with such a crown.

The job looks good though!

Don in Ohio
Link Posted: 3/11/2010 12:26:26 PM EDT
I did cut an 11 degree crown at first, but it just didn't look right. Ended up just doing the 90 degree recessed crown.
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