.243 Case trimmed length too short ?

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dirtykid

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Im just getting started reloading,and the 1st 200 rounds of .243 that I reloaded with 75gr V-max's and H4895 seemed to have performed well out of my REMMY-700, this time I noticed the cases had stretched to a tad-beyond the max, so I full-length resized them,and noticed they were a little on the long side after doing so (2.046 -2.049 )
I sat down to get them closer to the desired 2.035 and due to some sleepy eyes, ended up with a few as short as 2.029-2.032 trimmed case length,
Question being, is if as long as I end up with the correct OAL when bullet is seated, will I have any problems using the shortened-cases ?
(Besides the obvious appearance of the bullet not looking "seated")

Maybe Im giving that couple/1000's of an inch to much thought ?
 
with the correct OAL when bullet is seated,
CAse length has no effect on seated OAL.

OAL is set from the case head in the shell holder to the bullet ogive in the seating die.
A short neck will have exactly the same OAL as a long neck.

rc
 
I sometimes use one case to reform into a rarely available case. The necks might be a bit short on some examples. I find that if at least a caliber's length is available for the bullet to seat into and enough neck tension is there to hold the bullet from moving, there have been no problems. Usually it takes more reload cycles to run over max length with these rounds then also.:)
 
A little variation in case length is no problem, even if they are a tad short of published specs. The exception may be if you are going to crimp them. Getting a uniform crimp requires brass close to the same length. I don't suppose you will be crimping for 243.

Your casings grow a little in length each time they are fired and sized, after a number of loadings they will get long enough for the end of the neck to hit the end of the chamber. This crimps the casing into the bullet. When this happens, it can cause pressures to rise as the brass doesn't have the freedom to expand as it should to release the bullet. This is the reason for watching brass length and trimming.

I have no way of measuring exactly how much growth a casing can have in a specific rifle before long brass becomes a problem, but do know that there is some space for growth there before it becomes a problem in my rifles. What I am getting at is that you probably don't need to trim every time they are loaded, but check them.

If you are only loading for one rifle and using casings fired in that rifle, you may want to just neck size. You don't get near as much case stretching doing this.
 
No, that's no problem in terms of safe. As for the reduced time the bullet spends in the case it could have some bearing on velocity inconsistencies, but I doubt it would be enough to notice. The most important aspect of trimming is, not allowing your brass to grow beyond SAAMI maximum, as that can cause pressures to spike excessively high if the case mouth gets pinched between the bullet and throat.

GS
 
Thanks guys,I was more worried about bullet ""wobble" when fully seated due to lack of brass to hold it in place. I didnt think a few thousandths would matter, but I always
would rather err on the cautious side ,,
I do not usually trim cases until they reach or exceed max,and even then, like in this case,I was trying to trim back to about 2.035-2.038 (right about in the middle of spec)
between max and specified case-trim length,

Does anybody buy a case trimmer,and set it for a specific caliber and not any others ?
I know it would get expensive if a guy had a lot of different calibers, but trying to fine-tune a manual trimmer to the last thousandths of an inch really can get frustrating !
 
Yeah. It's the Lee trimmer. You buy the cutter and base once and then you buy individual pilots and lockrings tgat are caliber specific.
 
Looks like Im going shopping again , I picked up the Hornady manual trimmer from a co-worker for cheap, but its a pain to fine-tune, and it does not seem to hold the cases
real steady, you kinda gotta play with each case,as you lock it into place, and even then
I have found it "cants" the cases at an angle to the cutter ,, Frustrating !!

Witchunter, after I got it set to the correct length,everything comes out exactly at 2.035 , but I had about 8-10 cases that varied 4-5 thousandths either way,
I think I'll save them for the first few shots when zeroing a new scope or something
 
I just opened 2 new bags of Winchester 243 cases and it seems to me like they could use some quality control seeing as these cases are 2.032 in length out of the bag instead of 2.045. As they say, "close but no cigar". Using Nosler 55gr FBSP I'll try and seat them to obtain an overall length of 2.480 and go from there. This is a new gun I've never shot and we'll see how it goes.
 
I wouldn't worry about. It seems like all Winchester brass is .020 to .030 shorter than the trim to length when new.
 
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