PDA

View Full Version : Mandrel diameters



PEI Rob
02-16-2008, 04:58 PM
I was in the process of making a mandrel a few minutes ago and had to come in. I had a piece of scrap stainless lying around, most likely 300 series, and I now have it 10" long .7100" end to end and awefully pleased with myself for not having any taper. ;) I was thinking of using half of it for a Remington, Mauser at .710" and the other end for Savage at about .703". This piece is still in the chuck.

Do you think two diameters for two different actions would work and what two diameters would you guys suggest? I don't have a Rem here to check for a diameter.

I was thinking along the lines of chucking up the action jig and using the mandrel as a range rod to indicate the action in then true the threads, lugs and face.

Thanks,
Rob

Don
02-16-2008, 06:15 PM
I was in the process of making a mandrel a few minutes ago and had to come in. I had a piece of scrap stainless lying around, most likely 300 series, and I now have it 10" long .7100" end to end and awefully pleased with myself for not having any taper. ;) I was thinking of using half of it for a Remington, Mauser at .710" and the other end for Savage at about .703". This piece is still in the chuck.

Do you think two diameters for two different actions would work and what two diameters would you guys suggest? I don't have a Rem here to check for a diameter.

I was thinking along the lines of chucking up the action jig and using the mandrel as a range rod to indicate the action in then true the threads, lugs and face.

Thanks,
Rob

Multiple diameters on a 10" long rod wont work properly, large diameter wont fit in small diameter action.

Best to make a rod for each diameter with centers cut at each end.

Use the cheapest free-machining material possible, since you will have a selection on them. I like using leadloy, machines well, is rigid, and inexpensive..............Don

Kevin Cram
02-16-2008, 10:15 PM
I wouldn't recommend doing it that way at all. The through hole in a Remington will vary in size from front to rear, sometimes as much as a couple of thousandths. If your arbor just fits, it is probably just resting on either the front or the rear and not true with the centerline of the action. The best tool for the job is the one Greg Tannel sells. It has bushings that you fit precisely into the through hole. One in the front and one in the rear. A set comes in .0005" increments. The through hole in each bushing is constant and he makes a mandrel that slides through the bushings. Use his action trueing fixture or make your own. Use two .0001" indicators and you should have no problem dialing the action in to within .0001". You can then remove the mandrel leaving you full access to square up the receiver face, locking lugs and then square up the threads all in the same set-up. It's the best and most accurate way I've found to precisely true an action. You can read more about his action truing tools on his website, he also has a great video on how it works.

Bill Leeper
02-16-2008, 10:26 PM
Rob,
Remington , Savage, Ruger, Winchester, Mauser, Springfield, Enfield, are all from .701 to .705". I like to use a mandrel with bushings to fit each receiver since they all vary individually and from front to rear. Regards, Bill.

Clark
02-17-2008, 12:52 PM
It the lathe work is not perfect and there is a little taper to the mandrel, that can be a better fit for the 1903 - 1905 Mauser from Orberndorf.

PEI Rob
02-17-2008, 01:52 PM
Straight .7030" worked perfect, both ends fit tightly but surprisingly it will slide through. The set up resembles the one in Mike Bryant's pages. Floating bolt head on this action so even if I'm up to .001" off it will be fine. I'll make a good mandrel with bushings after I finish this project.

Thanks,
Rob