My usual case mouth prep proceidure is as fallows:
Regardless if brass needs trimming or not I champher and ream it with a RCBS/Wilson tool then I then take a correct for size phosforus-bronz brush, wrap the base of it with 0000 steel wool, screw it into an shortened old aluminium cleaning rod, chuck it in my Dewalt bat drill, then I take the bass in hand and while the drill is spinning at med rpm, pushing fermly,incert the brush/SW combo into the brass and polish the inside and outside of the case mouth for about 3 to 4 seconds.

I developed this proceidure after the standared champer/reaming didn't solve the problem of my brass shaving my bullets, at times rather badly.

My question is, is this power polishing of the inside and outside of my case mouths a good idea, or am I do I risk over polishing the case mouth and its a bad idea.

Without a doubt, if I don't power polish my case mouths, thay will shave my bullets. I have read here what I am doing is potentially a bad idea as it may affect the holding tension of my case mouths, although it hasn't to date, at least not that I can determine.

So what if any negative side affects are possible from my case mouth prep proceidure?

I can't think that steel wool is removing any brass to speak of. --Maybe knocking off some microscopic "pimples". On the other hand I can't see why you should be "shaving" bullets after a proper mouth chamfering. Can you tell us about the "chamfering tool" you are using---also you are using expander balls on your dies???
Also when you describe a "correct for size" brush I am thinking you might wrap a 6mm brush to hone a .308---something quite a bit smaller than the caliber you are cleaning??

Sounds like a solution to a problem that shouldn't exist. Buy a VLD chamfer tool from Midway and stop all the extra work you're doing.

Or I could say been there done that. It fits because I had,(HAD), the same problem until I got the VLD,(Lyman) chamfer tool. It stands for very low drag, it's a longer taper than the standard chamfer tool.

Art,

I use a similar prep. for my cases, and it works like a charm. The chamfer tool will leave a burr, although not really visible. The 0000 wool will polish the mouth of the case and leave it smooth.

I actually spin the case and hold the steel wool in my hand, but it works the same.

Just the way I do it ,,,,,

[ 10-28-2003, 06:19: Message edited by: Ma Bell ]

That is interesting. I'm curious what your expander measures compared to the bullets you are using. I believe you want .001" - .004" smaller neck expansion then bullet diameter.

How many times have your cases been reloaded? I'm wondering if the brass hasn't flowed into the neck and reduced the diameter causing your bullets to be shaved when seating. If so you can ream them from the inside with a Forster reamer or preferrably turn your necks to get rid of the excessive thickness. Neither is a delightful chore but sometimes has to be done. Best wishes.

Cal - Montreal

Try a K&M case mouth chamfer tool, I have eliminated all my seating problems with this tool(no more scratched bullets) and my runout numbers were improved as well. I was having problems using the standard 45deg chamfer tool as it created another sharp edge inside the case, the shallow angle of the K&M allows for a very smooth transition.

First I would like to thanks to all who responded.

To answer the questions asked:
Krackey I use a RCBS Burring tool made for them by Wilson.
T/C Nimrod, I have always used only Redding dies with both the fixed expander ball and the new "free floating expanding coller. The shaving problem occured when I used both, but now that some one mentioned it, the inside neck size might be the problem.
Cal Sibley, I think it only happens with new brass, but I cant find all my reloading notes as I moved to a new house only a month ago and are still unpacking.
I will take the advice given and buy a new de-burring tool and see if that helps.

At any rate I am quite happy my case prep procedure is not putting my brass at risk. I will buy a new tool and see what happens. If it solves my problem, I will post to that affect.

My most sincere thanks to all who took the time to help me out with their knowledge.

Regards, Art.

The angle on the Foster inside neck chamfering tool is too steep. It must be 30 degrees. I have been using a 15 degree tool made for some other industrial purpose. with a chamfer made by this tool bullets will seat with a nice easy soft feel.

I saw a tool for sale in a gunshop made by Lyman and it seemed like a good angle.

I polish the inside of my cases (all) with a stainless .22 cal wire(spiral) brush. I can do this with my bat. drill with the brush directly in the chuck. After polishing I lube the necks and neck size.I then use a Lee holder in the chuck and polish(nevr dull polish),wipe with towell,trim with Lee trimmer,deburr with RCBS tool & smooth trim with stainless steel wool pad held against mouth.Maybe to overcome your rough necks all you have to do is acquire a stainless pad and run your necks on it.It really does a nice smoothing job.

I'v had the same problem with new brass,and was told that it may just be some extra "springy" stuff,and to try the VLD chamfer tool.It solved the problem! Lymans about the cheapest at $6-$7 and the Hollands and the K&M in the $20-$25 range. All have varying degrees of taper.

[ 10-29-2003, 10:58: Message edited by: jsr ]