Case lubing question

04 June 2002, 02:55

Dino32HR

Hi y'all !

Well troops, I did it - I am now a former member of the straight-walled reloading club and have just purchased my first T/C barrel using a necked cartridge. A wildcat to boot !

I just bought a 10" 7mm TCU for IHMSA Standing Big Bore. [Big Grin]

I have a question or three about lubing. I'm told by the former owner that I'll need to neck size and bump the shoulder back on the brass about 0.001" after each firing. I know there's a slew of lubricants out there, but I'm straight-wall, carbide-die spoiled and don't really want to add the steps of applying and then cleaning case lube off the brass if I don't have to.

I've heard-tell that you can use powdered mica or even extra-fine graphite to lube the case neck and not have to clean the brass after.

Is this true?
Is this a recommended method?
Is there a downside to "dry" lubing?

I know I'll have to wet-lube for full-length resizing, but fully anticipate that I'll be able to just neck size and bump the shoulder back a touch after each firing most of the time after that. I do not plan on running these rounds very hot. A 139 gr. PSP bullet at 1,650 - 1,750 fps is the plan.

Can't wait to touch a few of these off !

Thanks a heap folks -

[ 06-04-2002, 17:13: Message edited by: Dino32HR ]

04 June 2002, 06:08

Paul H

I've been using Lee's case lube for bottleneck rounds, and have been happy with it. A quick wipe with a cloth will take off whatever is left.

If you haven't already read it, go to Mike Bellm's website and read the article, "The experiment every contender owner should do". I tried other suggested methods for sizing bottleneck contender rounds, but Mikes method is the only one that really made sence, and it definately works.

11 June 2002, 04:39

Dino32HR

Paul,

Thank you for your response. I've read Mike's page and found it very informative. I've got a lot of learning to do with necked cartridges ! I've read page upon page of how to reload necked cartridges, but lack the practical experience. A friend I shoot with has a ton of experience with them. I'll make sure my first couple of sessions are under his watchful eye.

Thanks again,
Tom

11 June 2002, 06:30

<.>

Most of the reading I've seen says that bumping the shoulder back generates head space problems. On a fire formed case why would you change the shoulder when it fits the chamber in the first place?

11 June 2002, 06:56

Bigdaddytacp

quote:
Originally posted by Genghis:
Most of the reading I've seen says that bumping the shoulder back generates head space problems. On a fire formed case why would you change the shoulder when it fits the chamber in the first place?

You don't want to set the shoulder back but a few thousandths....esp in a break open gun you don't have the camming power of a bolt so it needs a little room to seat in the chamber solidly and thus the brass is worked less and last longer.......some brass is more elastic than others and some springs back more and requires different amounts of sizing....your gun/brass and dies will tell you when you set the shoulder back just to allow easy action closing.....good luck and good shooting!!!

11 June 2002, 07:17

<centerpunch>

[ 06-15-2002, 03:43: Message edited by: centerpunch ]

12 June 2002, 02:00

Dino32HR

quote:
Originally posted by Genghis:
Most of the reading I've seen says that bumping the shoulder back generates head space problems. On a fire formed case why would you change the shoulder when it fits the chamber in the first place?

Genghis,

I am a raw rookie in reloading shoulder-type cartridges, however, I've been told by many that due to frame stretch upon firing in the T/C, the case will grow around .001", depending on the load. Given that, and the advice of the previous owner of the barrel, I've been advised to watch for this occurence. The cases have been fire-formed in this barrel.

I have a fixture for my dial calipers that measures the distance from the bottom of the case head to the mid-point on the angle of the shoulder. I have this critical dimension to use as a datum point. Knowing this dimension and the fact that it headspaces perfectly in my chamber, should allow me to maintain near-exact headspacing.

If this doesn't make sense to you all of massive experience, please let me know ! I'm always willing to listen and learn to the voices of experience.

Thanks to all for the sage advice. This foray into loading and shooting wildcats will be interesting for me. Straight-walled was almost too simple. [Wink]

I look forward to the challenge !