Inside neck reamer

[zap]

That sand paper sounds good until it falls into the case, then more problems, lol.
Thanks for all the replies all !!

 

[amlevin]

Not sure… Here to me is the dilemma.

You want the reamer to basically just take out the donut and bring it down to neck dimensions. So that means your reamer has to be very closed to neck dimensions. The problem is the closer it is to neck dimensions, the more difficulty you are going to have sliding it down the neck without scoring the neck or getting stuck.

If you have the neck sloppy like the Wilson, you are then less likely to score the neck but your reaming will likely be off centered which mean you will miss some of the donuts or score too deep in other areas.

I just don’t see how to get around this… I would be delighted to try but before I do, I feel I have to work though the above conflict in logic.

I've found that the RCBS "Pilot/Reamer" for their case trimmer works great. Just be sure to take a brush to the cutting part and remove any "chips" before taking on the next case. It's real snug on a sized case using RCBS die and expander so some lube will really help. I just use a q-tip dipped in some leftover motor oil from the bottle I used to fill my truck engine.

 

[jlow]

Not sure… Here to me is the dilemma.

You want the reamer to basically just take out the donut and bring it down to neck dimensions. So that means your reamer has to be very closed to neck dimensions. The problem is the closer it is to neck dimensions, the more difficulty you are going to have sliding it down the neck without scoring the neck or getting stuck.

If you have the neck sloppy like the Wilson, you are then less likely to score the neck but your reaming will likely be off centered which mean you will miss some of the donuts or score too deep in other areas.

I just don’t see how to get around this… I would be delighted to try but before I do, I feel I have to work though the above conflict in logic.

I've found that the RCBS "Pilot/Reamer" for their case trimmer works great. Just be sure to take a brush to the cutting part and remove any "chips" before taking on the next case. It's real snug on a sized case using RCBS die and expander so some lube will really help. I just use a q-tip dipped in some leftover motor oil from the bottle I used to fill my truck engine.

So for you guys that still use a reamer, how do you get it in there without scratching the inside of the neck when the fit is snug. Once you get it in there, do you stop when you feel the donut and then the question is how you turn the reamer? Hand power?

How does the pilot work?

 

[spclark]

...how do you get it in there without scratching the inside of the neck when the fit is snug. Once you get it in there, do you stop when you feel the donut and then the question is how you turn the reamer? Hand power?

The Wilson reamers will cut the neck insides full length unless you order a custom-profile as TimP found necessary. When I ream necks I'm cutting the entire length as I want a uniform surface against which a mandrel will bear when I go to turn the outsides.

For this to work properly I full-length size necks either with a full-length die that has an appropriate neck ID portion - one that will size necks down enough that an expander mandrel is needed to bring them back up to an ID appropriate for turning - or a bushing neck die set up with two bushings: the lower sizes to desired ID while the upper is a larger bore so that too-long necks can pass thru without running up against the die stem stop nut.

I ream necks "long" expecting to cut away the excess once reaming & turning has been completed. For 6HAGAR this amounts to about 0.300" off the .25 or .30REM cases we used; for 6XC made from Lapua Palma brass it's more like 0.180".

So far, with this procedure and with neck turning the outside surface to cut into the shoulder a little bit, I've avoided donuts in both cartridges. That I have chambers suited to load the bullets I prefer with their bearing surface ahead of where they'd encounter a donut is reassuring.

When I embarked on the 6HAGAR brass project (300 cases!!) I quickly tired of turning a neck reamer by hand. The handle is knurled but only about 1-1/4" diameter, tough on older arthritic fingers. Rather than going with a powered rig I found a hardware store die holder - the two-handle kind you put small, six-sided threading dies into - could be pressed onto the reamer's handle. This provides vastly more leverage, much better feel when operating. I did have to raise my Wilson trimmer rig up with a 7/8" thick wood block so as to provide more clearance between the die holder's handles and my reloading bench top.

 

[jlow]

...how do you get it in there without scratching the inside of the neck when the fit is snug. Once you get it in there, do you stop when you feel the donut and then the question is how you turn the reamer? Hand power?

The Wilson reamers will cut the neck insides full length unless you order a custom-profile as TimP found necessary. When I ream necks I'm cutting the entire length as I want a uniform surface against which a mandrel will bear when I go to turn the outsides.

For this to work properly I full-length size necks either with a full-length die that has an appropriate neck ID portion - one that will size necks down enough that an expander mandrel is needed to bring them back up to an ID appropriate for turning - or a bushing neck die set up with two bushings: the lower sizes to desired ID while the upper is a larger bore so that too-long necks can pass thru without running up against the die stem stop nut.

I ream necks "long" expecting to cut away the excess once reaming & turning has been completed. For 6HAGAR this amounts to about 0.300" off the .25 or .30REM cases we used; for 6XC made from Lapua Palma brass it's more like 0.180".

So far, with this procedure and with neck turning the outside surface to cut into the shoulder a little bit, I've avoided donuts in both cartridges. That I have chambers suited to load the bullets I prefer with their bearing surface ahead of where they'd encounter a donut is reassuring.

When I embarked on the 6HAGAR brass project (300 cases!!) I quickly tired of turning a neck reamer by hand. The handle is knurled but only about 1-1/4" diameter, tough on older arthritic fingers. Rather than going with a powered rig I found a hardware store die holder - the two-handle kind you put small, six-sided threading dies into - could be pressed onto the reamer's handle. This provides vastly more leverage, much better feel when operating. I did have to raise my Wilson trimmer rig up with a 7/8" thick wood block so as to provide more clearance between the die holder's handles and my reloading bench top.

Wow! I say wow! That’s quite the great post – thank you!

A couple of points. I understand that you cut the entire length but at least from my own limited exposure to reamers, it is a bit hard to start the cut straight?

As for a custom-profile reamer, do you know what is different about that profile?

I presume that donuts like neck lengthening after firing is a constant process, do you have to do this over and over again? Just wondering what this does to neck thickness.

That idea of using two bushing is interesting. This has to be the first time I have heard of it. The same for the hardware store die holder – some great ideas….

 

[noload]

REPLY#9Buy a chucking reamer from mc master and go to work. You can get them in .0005" sizes. Most are about $20.


Another thing to try, just sayin.

Joe Hynes


Like Joe said....I turn outside, shoot and when the donut needs cutting out, do it when the neck is blow out to .264 by hand with a .264 reamer. Thats how I deal with all my donuts all calibers.

 

[spclark]

Wilson's trimming jig holds neck reamer steaight at start. You can see hardware store die holder at right. No idea what kind of profile to ask for custom reamer; what I use is their standard item. I've had donuts form on factory Norma 6XC brass, not yet on what I've made from Lapua Palma brass.

I suppose a chucking reamer'd work too if you can hold it on-axis.

Came up with the two bushing idea to overcome need of trimming too long necks during forming process. Top bushing acts as a spacer, keeping stem nut far away from case mouth. Much of that extra-long neck gets trimmed away later on.

 

[noload]

'" " "I suppose a chucking reamer'd work too if you can hold it on-axis"

The reamer is held on axis by sliding in the neck before it touches the donut. My reamer has a taper at the start point.

 

[jlow]

Wilson's trimming jig holds neck reamer steaight at start. You can see hardware store die holder at right. No idea what kind of profile to ask for custom reamer; what I use is their standard item. I've had donuts form on factory Norma 6XC brass, not yet on what I've made from Lapua Palma brass.

I suppose a chucking reamer'd work too if you can hold it on-axis.

Came up with the two bushing idea to overcome need of trimming too long necks during forming process. Top bushing acts as a spacer, keeping stem nut far away from case mouth. Much of that extra-long neck gets trimmed away later on.

Nice - thanks again!

 

[amlevin]

So for you guys that still use a reamer, how do you get it in there without scratching the inside of the neck when the fit is snug. Once you get it in there, do you stop when you feel the donut and then the question is how you turn the reamer? Hand power?

How does the pilot work?

The RCBS pilot/reamer does not have conventional reamer "flutes". It's a smooth cylinder with a cutting "notch" cut in it. If it's kept free of burrs (I check it frequently with a small arkansas stone) it will slip into the case without scratching. When it encounters the donut, only then does it start cutting. It's only suitable for donut removal, not reducing neck thickness as some reamers like the Forster does.

FWIW, some neck turning "mandrels" have this same donut cutting feature on them.

 

[JamesnTN]

I had Wilson custom grind me my own inside neck reamers. What I wanted was the reamer to do two things, one cut out the donut and second I wanted to cut out the tight spots inside my necks where the brass flows. Now to do this you want the reamer cut .0001-.0002 over the did of your bullets being used. After you have fired your cases 4-6 times do not resize them setup your cases in your Wilson trimmer and run the reamer inside the necks. You will see and feel it cut out those tight spots. Once that has been done. You're good to go for many firings. After I have done the insides I'll stick the necks in some moly powder to recoat the inside necks and then resize the cases and run my normal process of the nylon brush inside the neck with a drill. I saw my ES go from 8-9 fps down to 3-4 fps from this process.