I am in the process of reloading some .270 cases. Most were purchased used and, as such, were full-length sized by me. A few cases were over the 2.540" maximum and were trimmed to that length. Many, however, measured down to 2.535" and, as such, needed bevelling only, with no trimming. When I get into this situation with case lengths that are not all the same, do I trim to the shortest case so that all the cases end up being the same length, or should I get an average and trim to that length so that the variance is only a couple of thousandths different, but not too far below the maximum published length, or if the difference between the lowest and highest measurement is only a few thousandths, do I just forget trimming so that they are all the same length, or what? If there is no perceptible effect on accuracy due to cases being slightly different lengths, I won't bother to trim them to equal lengths.

I know that cases should not go over the max length, but I have never read anything about a minimum lengths or about slight variations in lengths.

Max difference of .005 is fine to leave as is.

I would only trim if over max length.
Too short would be bad if you are crimping the case after seating the bullet

X2

Agreed, just bevel them and load em up.



----fl

The lengths fall within a .005" window, so I am loading them up. several were over the 2.540" limit and were trimmed. Thanks, guys.

When I load a batch of cases, I measure a few to see if any are over the maximum length. If they are, I trim the whole batch down to the "trim to length". This leaves a nice square, even neck, so you would have a more consistant neck tension on the bullet.

You said you "have never read anything about a minimum lengths". The maximum length and trim to lengths are listed in the reloading manuals.

Trim them all to the same length especially if you are crimping. A little too short is fine. The "Trim to" length is shorter than the "maximum". To save grief, get a Lee trimmer/ lock-stud and trim every time you reload. A quick twist will have them to the proper length without measuring and headscratching.~AMMOe

Get a Giraud Power Case trimmer like mine and let it decide which cases to trim for you. Very fast and efficient.

Lyman has a version that works with a drill press. That is what I use when I prepping 200 or 300 varmint rounds at a time. It uses the same collets and pilots as their bench mounted version.

I called Hornady. The tech said to go ahead and trim to the shortest length case in the batch, but not to exceed the minimum length. I have never run across cases less than the published minimum anyway, so I will just forget the maximum length trim and trim all cases to the shortest length in the batch. That way they are all the same length, falling between min and max. Makes sense to me. I have a motor-driven case trimmer (Gracey), but I have used it very little, since I load probably a maximum of 50 cases at a time for the .270. The Forster trimmer works fine for small amounts of brass. Trimming for the varmint rifles is another story since far more rounds are used up much more quickly than the .270. 100 .270 rounds will last me for the rest of my life....probably.

"should I get an average and trim to that length so that the variance is only a couple of thousandths different,"

If you think you have variation now, trim them all to excaltly the same length, then fire and resize-measure them again.

I know this is a little late, (last reply was 3 weeks ago) but how about measuring your chamber? The published max length is to cover all chambers. I trim .010" less than my actual chamber length.

Sinclair has the tool and it's cheap.
http://www.sinclairintl.com/product/11241/s

I realize this doesn't really answer your original question about what to do about uneven lengths but thought the info might be helpful.