Lyman Accutrimmer problem

[Jal5]

Anyone use this for trimming rifle brass? The pilot for 243 cases seems very tight in the case mouth even after I cleaned it a bit with emory paper. Seems like I have to force the trimmer head a lot to get any cutting action. Same thing happened with the 357 cases and that pilot too.

Maybe its just me not being used to this trimmer but I can't seem to get it set for trim to length correctly either, at least not anyway that I can duplicate the length case to case.

Frustrated,

Joe

[454PB]

I'm not familiar with the Lyman, but I've used several of the collet type trimmers and had the same problem.

The Hornady trimmer I have does a better job at repeatable settings because it uses a standard shell holder to hold the case, rather than a collet.

However, the most accurate trimmer I have is a Wilson. Each case is trimmed within .002" of the next, and can be used on sized or unsized cases.

I prefer to trim AFTER sizing for more accuracy in length, and that can be a problem with some pilots, since they are oversized to fit fired cases. I have reduced the diameter on all of mine for that reason.

[Jal5]

I will try reducing the dia. of the pilot and see how that works.

What about the inability to "fine tune" the length? Lyman uses a stop wheel with a tiny set screw that you adjust to get the last adjustment of a couple of thousandths for the right length. I set one up to the trim to length, then tighten the set screw, so the stop wheel cannot move and it limits the length the cutter can insert into the mouth of the case. But the next case isn't the same length, generally shorter! Lyman uses a standard shell holder too.

Joe

[anachronism]

Chuck the pilot in a drill & polish it a bit with emery cloth. I made my 338 pilot this way, from . .375 pilot

[1hole]

Those trimmers that use a standard shell holder with a screw that presses the shell in place are registering on the front edge of the rim. Any variation the the thickness of the rim will be reflected in the finished case length. Such small differences really have no significent effect.

[454PB]

1hole nailed it. That's why I like the Wilson.

[Jal5]

1Hole- so the tiny differences in finished case length, 1-3 thousandths are negligible?

Joe

[1hole]

I don't think any rifle has ever been made that will recognise such small differences, case length or OAL. Certainly not factory rifles with standard SAAMI chambers. The effects of unmeasureable differences in internal case volume or bore fouling will exceed that. IMHO.

[Jal5]

I reduced the dia. of the 243 pilot plus I made sure all the case mouths were expanded and that solved the fitting problem. Spinning the case several times as I trimmed resulted in a nice even trim, so I should be good to go. Thanks for the help!

Joe

[spqrzilla]

Sometimes a dull cutter will create a ridge of brass in the case mouth and "hook" on the pilot.