Am I overworking this 35 Rem brass?

[PBSmith]

It seems that I might be. ID case neck diameters are as follows:

Fired cases: 0.364"
After outside sizing with conventional Lee die (decapper removed): 0.345"
After inside expanding in Lyman M-die: 0.357" (case mouth belled to 0.360")

Loading soft-cast 160-200 grain bullets whose diameters range from 0.358-0.359."

I anneal case necks and haven't had a splitting problem, but can't see the need for all that working of the necks.

Is the Lee Collet Die a better way to arrive at the desired final inside neck diameter of 0.357? I could still use the M-die to get a belled case mouth.

What other options should I consider?

Thanks
PBSmith

edit: possibly a different brand of conventional dies would not take the necks down so drastically. However, without the option to try other brands of dies before purchasing, that would be a carp shoot.

[MyFlatline]

Good that you are annealing, that has saved my brass. I quit using the M die and started using the NOE expanders in the Lee dies. I need a true .361 to seat my .360 bullet to keep from shaving lead. The M die just put a big flare.

[PBSmith]

Good that you are annealing, that has saved my brass. I quit using the M die and started using the NOE expanders in the Lee dies. I need a true .361 to seat my .360 bullet to keep from shaving lead. The M die just put a big flare.

I read you on the NOE. If my bullet were any larger, I'd have to go that route. But the M-die does the job for a 359 bullet, and I use only the straight .357x360 portions of it - no flare.

What I'm trying to avoid in my sizing of the cases is going down to the 0.345" inside neck diameter that the standard or conventional Lee dies gives.

[country gent]

That does sound like a lot of "squeeze" on the neck in the sizing die. Ideally the sizing die would size down to .002-.003 under expander size in the die. This would allow for varyations in brass wall thickness and not work the brass near as much.

Unfortunately with a fixed die there arnt a lot of options available to change this. ( bushing dies are easy buy a bigger bushing and install it). There are ways to enlarge the neck portion of the die. You want to do this with care and patience since if you go to far you need to replace the die.

You can ream the neck out. A decimal hand reamer could be purchased and ran by hand with oil to aid. Measure neck dia of a loaded round and subtract .008-.010 from this. This is reamer dimension you want. this allows for the .003 size down past and .005 to finish polish the neck after reaming. This is done with very fine emery paper and a fine lapping compound or polish on a flannel patch with a mandrel.

You can open the neck up with the mandrel and emery paper in varying grots but this is a slow process for .010

Last would be to set up in lathe and bore the neck out to desired size leaving a couple thousandths for final polish. For this you would want carbide tooling.

[country gent]

Pm me and Ill send you my Phone number if you want to discuss this or want walked thru it.

[ulav8r]

With a fired diameter of .364, you should try using .363 diameter boolits. If they will feed, then modify your dies to get .361 after sizing andbell (M die) to .364.

[earlmck]

I kinda' like the Lee collet neck dies. I'd bet that would fix you up.

[rockrat]

You could go up to .363" boolits, but not necessary that you need to use that size. You will just have more neck clearance with a smaller boolit. It does seem your dies are sizing the neck down way too much, but I have seen other dies do that. tooling I guess gets worn and the makers just guess that the expander ball will take care of any problems. Overworks brass though. If you didn't anneal, you probably would have lost many a case so far.

I wouldn't think a reamer would work on the neck unless a carbide reamer, but then the hardening of the dies doesn't go that deep, a few thousandths I have read of, so your neck area would be in an unhardened state. Collet die sounds like it might be the best course.

[PBSmith]

Pm me and Ill send you my Phone number if you want to discuss this or want walked thru it.

Thanks country. I just sent a note to Lee, asking if the die might be under specification. Curious to see how they respond. Appreciate your input.

[PBSmith]

Thanks earl and rock. I'm trying to find out from Lee what their mandrel diameter is on the collet die.

[PBSmith]

With a fired diameter of .364, you should try using .363 diameter boolits. If they will feed, then modify your dies to get .361 after sizing andbell (M die) to .364.

So far I've been happy with the 0.359" Not to say that larger slugs wouldn't shoot better.

[slughammer]

Sometimes the mouth of the case remains sprung inward and makes measuring I.D. difficult. I usually do O.D. measurements to verify what I'm seeing.

I will say that I've dealt with some pretty rough surfaces in the necks of a couple of Lee dies that were over working my brass. I started with 320 emery paper held on a shaft and spun with a drill to polish them out. When taking out the roughness, the first few thou come out fairly easy and the diameter changes for the better as a result. Once there is a flat smooth surface, the progress is slower.

[PBSmith]

Sometimes the mouth of the case remains sprung inward and makes measuring I.D. difficult. I usually do O.D. measurements to verify what I'm seeing.

I will say that I've dealt with some pretty rough surfaces in the necks of a couple of Lee dies that were over working my brass. I started with 320 emery paper held on a shaft and spun with a drill to polish them out. When taking out the roughness, the first few thou come out fairly easy and the diameter changes for the better as a result. Once there is a flat smooth surface, the progress is slower.

Interesting. I heard back from Lee yesterday regarding my query about a possible undersized neck on their die. Their tech man didn't seem to be alarmed at my numbers. The expander plug on Lee's die set measures 0.356". With the sized ID neck measurement I made of 0.345" (after outside sizing with the Lee die, no expander plug), that means the case neck has to be expanded 0.011." I haven't compared this with other dies in other calibers, but I suspect it's way to much "squeeze," as County Gent said in his post.

As a low-cost satisfaction to my curiosity, I'm purchasing another brand of sizing die on e-bay to see how it does on the case neck. If no better than Lee, I'll give your emery cloth-on-stick a run. I'd prefer to do it the way Country Gent suggested, but I expect the reamer is pricey.

Thanks.

[country gent]

A decimal hand reamer is probably around $30.00

[1hole]

Sizer dies are case hardened. A file won't touch it and neither will a reamer.

Be careful about annealing brass. It's very easy to get the metal much too hot and that will destroy the neck's "squeeze" grip. Once that happens the brass grain structure will become soft and forever be changed and the hardness can't be restored.

(Soft case necks can be good for cast bullets but lack the elastic spring-back needed to hold jacketed bullets very well.)

[EDG]

You are working the brass quite a bit but it is not all the fault of the dies.
From .357 up to .364 is caused by your chamber every time you fire a case.
You can lap die necks out to reduce the sizing but you can't do much about your chamber.

[PBSmith]

Received another .35 Remington sizing die just now. It's an old number from Herter's. This die takes the necks down to 0.352 ID, seven thousandths larger than the Lee die I have been using.

If I can bring the sized ID up to 0.355-.356" by lapping the neck of the die, I will probably be happy using the M-die to expand out one or two thou.