Trimming Case Length

[22~308TargetShootr]

Anyone else notice this or is it just me, but i do all my case prep by hand, no power tools or case prep centers, yup it takes time but I don't mind. So I trim my .308 Hornady Match brass to 2.005, but I've noticed after I trim to 2.005 and smooth (chaffer) the outside and inside, then remeasure, it 99% of the time goes back to 2.006. So now I've been trimming to 2.004 then doing the edge smoothing, measuring again and getting my 2.005. Just me ? or anyone else have this happen and notice this ?

XChasn,

 

[hrfunk]

Re: Trimming Case Length

I have. I think what is happening is the very tip of the case mouth stretching slightly as you go through the chamfer/de-burring excercise. You'll notice similar deviations at other stages of case prep.

HRF

 

[FLIGHT762]

Re: Trimming Case Length

I can make a guess that when you trim and then "chamfer" the outside of the case, it moves the edge up .001" or so, which gives you the oversize reading. I'm glad you made the necessary adjustments to satisfy your infatuation of getting your cases to an exact 2.005"

I do not get the personal satisfaction you get out of doing your case preparations by hand. I prefer to use a RCBS case prep center to ream the inside flash hole, a Sinclair primer pocket uniformer in a low speed power drill to unifom my primer pockets and to trim, I use a Giraud trimmer. If I get a length of within .003" or so, It's okay with me.

 

[winxp_man]

Re: Trimming Case Length

This is why I use the 3 way cutter from RCBS it works so perfect

Aron-

 

[Fuzzball]

Re: Trimming Case Length

Necks don't grow due to chamfering. It's almost certainly a burr but a case lenght variation of 1 thou, or 5, is no effective variation at all.