JimKirk
Member
I came up with a simple solution to a problem I encountered right after purchasing my RCBC trimmer long ago.
The problem was that cartridge rim diameters vary quite a lot.
The RCBS trimmer uses a draw type collet to hold the case by the rim.
A smaller diameter rim will cause the collet to withdraw deeper into the chuck causing the case to be left longer than desired.
A larger rim would cause the rim not to be withdrawn as deep causing a shorter case than desired.
My solution was to turn a pilot, I used a .75" long steel rod .473" in diameter, which happens to be the rim diameter of the 30/06 case.
The pilot is inserted into the collet and tightened down, I do put a case on the cutter and the collet pilot at the same time to make sure it aligns correctly.
The collet pilot has a large primer sized(slightly smaller) protrusion turned on it.
The collet pilot for small primer uses a small primer sized protrusion on it.
I didn't think or I would have turned one size on one end and the other size on the opposite end.
To use the pilot, you place a case on the pilot and hold it toward the collet end and turn the cutter.
The case length does not vary because it is held between centers.
Attaching photos so you can see...
Hope this helps somebody with the same problem.
Jimmy K
The problem was that cartridge rim diameters vary quite a lot.
The RCBS trimmer uses a draw type collet to hold the case by the rim.
A smaller diameter rim will cause the collet to withdraw deeper into the chuck causing the case to be left longer than desired.
A larger rim would cause the rim not to be withdrawn as deep causing a shorter case than desired.
My solution was to turn a pilot, I used a .75" long steel rod .473" in diameter, which happens to be the rim diameter of the 30/06 case.
The pilot is inserted into the collet and tightened down, I do put a case on the cutter and the collet pilot at the same time to make sure it aligns correctly.
The collet pilot has a large primer sized(slightly smaller) protrusion turned on it.
The collet pilot for small primer uses a small primer sized protrusion on it.
I didn't think or I would have turned one size on one end and the other size on the opposite end.
To use the pilot, you place a case on the pilot and hold it toward the collet end and turn the cutter.
The case length does not vary because it is held between centers.
Attaching photos so you can see...
Hope this helps somebody with the same problem.
Jimmy K