Trimming a Creedmore

O

Old Stony

New member
I've been shooting a 6.5 Creedmore through a couple rifles for a while, and have been recently getting one set up in an AR platform for my night sight and hog hunting.
Trying to trim brass today I was getting really frustrated trying to get consistent lengths. I have been using my old RCBS trimmer. and not happy at all with it. It seems with that kind of collet holding he case, the amount of pressure put on the collet from tightening it up on the case determines a lot of the final length as the collet is screwed further back as it is tightened.
I have talked to guys that use the Lee trim die setup, and most don't seem very happy with it either. I love the file/trim dies, but can't seem to find anyone that is making one for this caliber.
Anyone know of a maker of a file die for 6.5 Creedmore?
 
Can the old trimmers that use collets be converted to use the newer style shell plates?

My RCBS trimmer works very well but it's the shellplate style.
 
Can't remember having these problems before. I took the trimmer all apart and cleaned and oiled everything, but no difference. I guess I better just bite the bullet and buy a new trimmer that doesn't use a collet. Sure wish RCBS would come out with a file die though.
 
Put the case into the collet and slide the cutter to it pushing into the collet. start turning and while turning, tighten the case enough to stop the case from turning. If the case goes into the trimmer the same every time, it can't give different length's unless your doing it wrong. That would be not finishing the cut.
 
under pressure

I used Hornady Trimmer.
It's probably fairly close to RCBS.
I've learned the importance of using the same pressure when turning the trimmer.

But also take into consideration toleration for LR-308 nigh hunting scenarios you are not going to be precision loading for 4 legged flea/tic bags.
 
I use a Forster and trim just like Don Fischer says he does and have been doing it since mid 80's.
Never had any issues unless set screw works loose, but I have addressed this by droping a piece of lead shot under the set screw.
 
I agree with the inconsistent case lengths. When using the collets from the old RCBS tool. I believe it is do to the cases having rims with different diameters. It might be best to sort cases for now by case rim diameters. I have seen the shell plate holders that can be swapped out. Try contacting RCBS hopefully they will back you up. I switched to the Wilson sleeve case holders it seams to be a much more consistent way to go. Oldscot3 is correct.
 
I tried two of them. One a hand trimmer and one the RCBS

Neither worked without constant cross checks (the hand trimmer pin works great for poking grit out of the primer holes though)

Get a Gerard Tri Trimmer. Costs about $100, never look back. You can chuck a drill into a vice and its even better.

It is very consistent and well and at most .003 variation.

Lots of calibers (more than 3) get the motorized one they sell. It is good and has more cartridge options.

Does the trim off the shoulder, consistent and does chamber and de-burr.

All others are inferior. It is nice but does not de-burr or chamfer.
 
There is one trimmer that is slightly more consistent on overall case length than any other: The Lee trimmer. Coupled with either a drill press or their Zip-trim, it is reasonably fast. If all my cases are from the same lot and have the same load history, I would say it stays within a spread of 0.0015-0.0020" most of the time, and where there is error it is due to case head burrs or rim bends from how the case was handled and ejected. Hitting gravel or hard extraction from a self-loader can cause irregularities here. the Lee trim length is fixed (though you can shorted the Lee permanently by grinding, you can't put it back again. On the other hand, a new gauge part that is factory length is only $6 if you don't like where your grinding leaves you).

In very close second place is the Wilson, with maybe half a thousandth to a thousandth more variation at most, and about equally good when you establish a rhythm and consistent force level seating cases into the holder. Absent that, varying force applied tapping cases into the holder can stretch them a little differently and interfere with repeatability. But it is pretty darn good. A big advantages that the Wilson is adjustable. Like the Lee, its precision is vulnerable to head dings and irregularities. If you are really ambitious, though, you can turn a case around in the Wilson and cut small burrs off the head with its trim cutter to improve flatness.

The Giraud registers on the case shoulder, same as the Gracey, WFT, and Possum Hollow trimmers. However, this does not produce the most exact overall case length as that number is then dependent on how consistently your sizing die sets the shoulder back, a number that frequently varies a thousandth or two within a headstamp, and can vary a little more between headstamps due to hardness and spring-back difference affecting exact resizing. However, if all the cases are from the same lot and have the same load history, its accuracy is about like the Wilson's as the resizing operation is then maximally consistent.
 
I trim cases for overall length from the base to the mouth. I like my Lyman case trimmer because the universal shell holder holds the case against a solid base. That base indexes the cartridge in the same place every time. The cutter head rotates and is positioned with a positive stop as well. There are no collets with tapered bores and stepped shoulders that change the distance from the cartridge base to the mouth. My trimmer is set at the length of the shortest cartridge and I just slip bushings in for the cartridge I am trimming. The cases are trimmed to a tolerance of under .001" and they are trimmed to that same length every time. No adjustments are required when changing from one caliber to the next. (other than the pilot and the bushing) The cases I trimmed last year are the same length as the ones I trimmed yesterday.
 
You must log in or register to reply here.
Back
Top