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6mm expander mandrel

It seems most places are sold out. But would anyone happen to have a .242 expander mandrel they would want to part ways with?

I'm hoping by removing the expander ball on my full length bushing die and passing it through a expander mandrel I can get better concintricity and more consistent neck tension. Between this and annealing more regularly I'm hoping to start eliminating those pesky ones that seem to wander off a little bit from the pack.

Any thoughts?
 
I have a Sinclair 6mm expander mandrel that measures .2422, or a not-atypical (for Sinclair) .0008 below bullet diameter. I have three other sizes, all .0008 below bullet, and one (25 cal) that's .0009 under.

PS

And yes, the 6mm is on backorder at Sinclair's. o_O
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I called KM reloading and they are shipping me one if there complete setups for 6mm. My only concern is I think theirs may be a little light on neck tension. He says theirs measures .2433. So with spring back I may be below .001 neck tension. I don't shoot any of my 6mm rounds in a "jam" so hopefully it will work out. I'm just trying to eliminate any concentricity issues. My groups are decent but my competition is slightly edging me out and I know for sure I have room for improvement in my reloading process. The other 80% is this nut behind the trigger but I'm stubborn so I gotta get the other 20% taken care of as soon as possible! Thanks for all the help guys!
 
I called KM reloading and they are shipping me one if there complete setups for 6mm. My only concern is I think theirs may be a little light on neck tension. He says theirs measures .2433. So with spring back I may be below .001 neck tension. I don't shoot any of my 6mm rounds in a "jam" so hopefully it will work out. I'm just trying to eliminate any concentricity issues. My groups are decent but my competition is slightly edging me out and I know for sure I have room for improvement in my reloading process. The other 80% is this nut behind the trigger but I'm stubborn so I gotta get the other 20% taken care of as soon as possible! Thanks for all the help guys!

I think you ordered the standard sized expander for neck turning. This is the custom sized mandrels for doing what you want.

http://kmshooting.com/case-neck-exp...rel-kits/custom-standard-expand-mandrels.html
 
Been there and done that. I asked Roger for a custom mandrel and when I got it it wasn't within a thousand of what I asked. When I called and told that he said that it depends on the micrometer that you use, when I responded that I use a Mitutoyo micrometer and that I wanted to return it for a refund he hung up on me.

Now I get accurate mandrels (Vermont gage) off Amazon for $3 not $27.

Joe
So you purchase the desired size and chuck it into a collet style die and use it as your expander mandrel? Do you purchase the go gage style at the diameter you want? The ones I see on amazon don't have a long taper on one end so that sparked my question
 
The mandrel die and pin set in Joe's posts above are the cat's meow. The beauty of that collet die is the ability to change the pin gauge to different sizes in minutes in order to change neck tension. Joe turned me on to Kenny Porter's die which I bought for my 6.5 Creedmoor. I have a set of pin gauges (.061" - .500") that I use in my shop so I'm covered. To use Kenny's die for my 6PPC or .223 I just bought a different collet and then use the pin gauges to find the neck ID I want, I didn't have to buy another die body. Yeah, you'll have to chamfer one end of the pin gauge for easy entry into the neck mouth but that's easy peasy.
 
Been there and done that. I asked Roger for a custom mandrel and when I got it it wasn't within a thousand of what I asked. When I called and told that he said that it depends on the micrometer that you use, when I responded that I use a Mitutoyo micrometer and that I wanted to return it for a refund he hung up on me.

Now I get accurate mandrels (Vermont gage) off Amazon for $3 not $27.

Joe
Great shout! Just ordered 3 for $16. I'll machine them so i can duplicate them to fit my current K&M expander assembly
 
Great shout! Just ordered 3 for $16. I'll machine them so i can duplicate them to fit my current K&M expander assembly
I have a K&M setup and I would be interested how you machine these to fit it. The mandrel I got from them left me with a little too light of tension. My groups opened up a bit so I'm working back down on mandrel size.
 
I have a K&M setup and I would be interested how you machine these to fit it. The mandrel I got from them left me with a little too light of tension. My groups opened up a bit so I'm working back down on mandrel size.

You have never said what cartridge you are loading, but from the indicated mandrel size you have , it is a 6 mm something.
Are you sizing with a bushing die? If so, what size bushing are you using and do you have any smaller sized bushings? There may be a work around.
 
k&m will make you any size mandrel you want

I ordered the standard neck turning mandrels and made them myself. Sat down at the bench with some 220, 320, 400, grit emery cloth, cordless drill, micrometer and some 1500 grit wet or dry sandpaper for the final finish and made my own. Takes about 15 to 20 minutes each depending on how far you are taking it down.
I think my English teacher called that a run on sentence. But you get the point.
 
I have a K&M setup and I would be interested how you machine these to fit it. The mandrel I got from them left me with a little too light of tension. My groups opened up a bit so I'm working back down on mandrel size.

Iv bought a .261 a .2615 and a .262. I have a tap aleady that allows me to screw it into the holder. All I'm looking to do is cut a light taper on the end and a relief so that is replicates the K&M shape. Ill leave the honed size untouched so i get a true reading for the sizes i have ordered. I'll post up the results when I'm done.
 
You have never said what cartridge you are loading, but from the indicated mandrel size you have , it is a 6 mm something.
Are you sizing with a bushing die? If so, what size bushing are you using and do you have any smaller sized bushings? There may be a work around.
I am shooting 6xc, Redding full length bushing die. .268 bushing. Loaded necks measure .270. Norma brass.

Wife shoots a 6br. Lapua brass.
 
I am shooting 6xc, Redding full length bushing die. .268 bushing. Loaded necks measure .270. Norma brass.

Wife shoots a 6br. Lapua brass.

If it was me and I wanted a little more neck tension, I would get some 320 emery cloth and 1500 wet or dry and take off about .0005, then do some sizing, measuring and shooting. If that don't suit you, take of another .0005 and repeat. What do you have to lose? I think the Std mandrel is $12. About the cost of a stop at Starbucks.
 
If it was me and I wanted a little more neck tension, I would get some 320 emery cloth and 1500 wet or dry and take off about .0005, then do some sizing, measuring and shooting. If that don't suit you, take of another .0005 and repeat. What do you have to lose? I think the Std mandrel is $12. About the cost of a stop at Starbucks.
Sounds like a plan to me. Thanks
 

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