Annealing winchester 300WSM brass.

[Centre Punch]

Has anyone had the same problem as me when i came to neck turn my Win 300wsm brass for a light clean up cut.
I expanded the necks with my K&M expanderon,but when i slid the case onto the turning tool mandrel, the mandrel would not pass the juncture of the neck and the shoulder, A couple of extra passes up the expander allowed the turning mandrel to go past the neck/shoulder juncture but it was so tight there was no way you could turn it. /ubbthreads/images/graemlins/mad.gif

I ummed and arred about it for a while and decided to heat a case with my blowtorch and give that a try. HEY PRESTO it worked the case fitted perfectly over the turning mandrel.

I then annealed the remaining 99 cases,and i have had no further problems.(even though it was a long process.).

PS.before anyone asks if i have tried Norma brass,the answer is NO! not at £99 per 100 here in the UK (nearly $200) /ubbthreads/images/graemlins/shocked.gif

Merry Christmas. /ubbthreads/images/graemlins/smile.gif

 

[Ian M]

Punch,
I believe that you have the Stealth in .300WSM. Today I talked to Winchester and they did indeed have interest expressed from a European supplier for some Controlled Round Feed Stealths in .300 WSM. Said that there was a definite preferance for the CRF vs the push feed or CRF-push feed that is now out.
You have a rifle that I wish we could get over here! For some reason they have not put such a rifle into their lineup - sure hope it happens.

 

[Brent]

There's a tight spot (thicker brass, a doughnut) that forms at the neck shoulder juncture and this is why Ken sells a fluted carbide reamer / mandrel for the K&M turner. This heavily supported area will also spring back more than the rest of the unsupported neck as it resists expanding much more and always be tight, even from the factory. Once cut with the carbide reamer mandrel necks will not pinch the bullets if seated that deeply, or the normal mandrel when neck turning. The reamer mandrels are all I use and they work great... $35 I think.

If you run the expandiron mandrel into the neck of a annealed case and one that is not annealed, you will only get a consistant ID afterward for your neck turning mandrel to run on if the case neck was first uniform in support, hardness, thickness etc. The additional support given by the shoulder will always leave the ID in the neck/shoulder juncture tighter when expanding it, always. Lowering the blades on the caliper deeper and deeper into the neck will easily reveal the difference in ID and location it begins to get tighter.

I would guess that if the neck turning mandrel fit through the neck/shoulder juncture, it was fitting looser above this point... which is not desirable for consistant neck thickness.

 

[Centre Punch]

Brent,
Thanks for that invaluable information. I was aware of this cutter/mandrel,but thought its application was for use with brass which had many reloads and was starting to form doughnuts from constant neck sizing. I had never experienced this problem with new brass before,even with my 6mm PPC( formed from Lapua 220 russian cases) which had been neck sized many times. Could it be somthing to do with the steep shoulder angle,maybe? I may dump this batch of brass,because of the annealling it has lost its spring back when sized in a .333" bushing (.002" under loaded round diametre,after turning) it stays at .331", /ubbthreads/images/graemlins/frown.gif (fired brass measures.344",so you can see it gets squashed down quite a bit. I've tried a .335" dia bushing and gives satisfactory case neck tension, but i'm not happy. A cutter/mandrel was ordered this morning and i am curious to see if the same thing with my next batch of brass. and if it does i will be prepared. /ubbthreads/images/graemlins/smile.gif

Merry Christmas.

 

[Brent]

CP

I think your brass may be ok still, the .335 bushing is about right in order to arive at a .333 OD and here's why;

If you size down the necks that much, more than a few thou, what happens is the brass as it enters the bushing ID will actually overshoot the ID because of the angle it enters at and end up smaller than the ID. This is most common with factory chambers with near .010" total clearance in the neck area.

What you'll see with tight neck chambers with just a couple thou total clearance is that when sized the necks will end up larger than bushing ID because the necks enter the bushing a basically a zero angle, then springback allows them to get a thou or two larger when withdrawn.

The only chambers that will work closely are the "tighter than factory spec" but not real tight chambers. Somewhere in the .005 total clearance area. When the necks enter the bushing at enough of an angle that it produces necks that are undersize by an amount equal to the brass springback amount, it will equal the exact bushing ID... one usually overrides the other though.

Now, neck tension change again when brass gets harder and springback is affected... this is just something you need to watch, and you may need a size smaller bushing if you run just .001 - .002 total neck tension (press fit). Also accuracy may fall if nk tension changes... it can happen in a big way.

Taking carefull measurements during each the sizing operations will tell you what's happening and what needs to be done to end up where you desired to.

 

[Centre Punch]

Brent,
Once again thanks for the info, much obliged.

A niggly little thing you may be able to clear up for me, do Redding and Wilson bushings actually size to the given dimension, meaning the ID is actually smaller and accounts for springback, or is the ID the actual stated dimension. I ask this because i have never actually measured the bore of a bushing and just took it for granted that this would be the neck diametre as specified.

IanM,
I have been trying to send you an e-mail re: my Stealth but have been having problems sending international e-mails. I have some pictures and some interesting information, so please be patient while i work out my problems, thanks.

 

[Brent]

The actual ID is stamped on the bushing. What OD our necks ends up just depends on too many things.