Going to be loading 38 special for my father in the near future, have started prepping a bunch of once fired cases. I know with roll-crimped cases the case length is much more important to watch-in order for the roll-crimp to be uniform in the cannelure. The case I have are a mix of nickel & brass. Noticed when measuring the nickle they are consistant at 1.149", while the brass is consistant at 1.151". From my reading 1.149" is the magic number of reference. Is the 2 thousands going to affect the loading so that I need to trim the brass?

Thanks in advance!

.002 isn't going to make a difference.

No. Set your micrometer to .002 and see how much it is. Insignificant.

__________________
Still Running Against the Wind

Considering I have never ever trimmed a .38 Special case you can guess I think it means nothing. Two Tenths might mean something but two Thousands means nothing in case length.

I don't even think the human eye can see that small a difference.

__________________
Freedom is never free!!
SWCA #3437

For reference, computer paper is about .003 in. thick.
I have never trimmed my 38 cal brass, and am on about the 20th use.

rat

Thanks for the confirmation guys--I didn't think that .002 would affect the roll-crimp into the cannelure. My worst fear was having to buy a trimmer, to trim off .002--think I would throw the brass in my scrap bucket if that was the case.

That would not be any fun. Never trimmed nor measured a straight wall case.

There is probably more variance in the bullets and groove.

As Arch stated you can't even see it, I sure can't

__________________
Still Running Against the Wind

I have never trimmed any handgun brass.
Rifle brass is a different thing.

Bought my first S&W 38 Sp. in 1956. been reloading that caliber ever since. Never have trimmed 38 Sp. Don't need to. In fact I still have some military REM-UMC brass I picked up while in the Guard. Still using them

HECK!

I don't even OWN a case trimmer! Never had the need and I have reloaded my .38's and .45's so many times I have lost track.

I do keep an eye out for severely stretched .45-70 and .38-55 Rifle cases but I have not encountered any problems yet. I load those for Marlin Lever Rifles and I keep them on the mild side so I think I will be fine there as well.

Chief38

While it is true straight walled pistol cases don't need trimming [I]usually[I], brass that has been fired with near "never exceed" listed powder charges or excessive crimp do stretch. I have had to trim my .44 remington magnum cases. Measuring cases is a step I never omit. I have had the occasional never fired brass case from Midway brass need trimmed. It is just good technique to check. PS. there are case trimmers like the Lee Zip trim that do a great job for low $s. If you reload you will eventually need a case trimmer.

When I first purchase pistol brass, I measure about a dozen cases. If they are less than recommended trim length, I load them as is. If they are more than trim length, I have at it.

FWIW, I've never had to trim pistol brass a second time and no longer even bother measuring them other than when new.

When I first started reloading for the 44 magnum and redhawk I had a rather large selection of 44 mag brass that I had picked up over the years. Wasn't too much trouble to round up 100 cases with the same headstamp. So I started out with 100 winchester cases. I measured all 100 cases and marked each one, then set the trimmer so it would square up the case mouth of the smallest case. Set the trimmer at that length. Did all 100 at that same length. I'm using H110 which requires a firm crimp. When finished reloading the 100 cases all show perfect crimps. Same thing with 38 special. Now 45acp I don't bother measuring or trimming. Just clean the primer pockets and load them up. Why? because I have not found one case that was anywhere near the trim to length. And this is with mixed cases. Those 45 rounds have all chambered perfectly, fired and ejected perfectly without all the trial and tribulations done with the revolver cases. Frank

Once you start loading for a Model 52 - uniform case length and uniform trim will be very important .

Well to post an update, I've loaded up 100 rounds of 38 Special for my father's S&W 686, have not trimmed any and they seem to be working well.

The only real value in trimming (for rimmed cases) is to have consistent crimp (or trim off small cracks) So long as you do not have cases that exceed max case length. . Light loads, should have good crimp to insure good combustion. Heavy loads should have good crimp to keep bullets from "backing out" of case. Cases longer than max for the caliber could "pinch" the bullets in the case and might be very over pressure. Since you have "only" two lengths it would be easier to adjust the crimp die for each batch (probably not even needed for .002 inch) than do trimming.

.38 is exceedingly forgiving and just about whatever you'll put together will load and shoot.

__________________
"He was kinda funny lookin'"

As a note;

the maximum for the 38 Special case OAL is 1.155"..........

You will probably have problems with accuracy right now with cases too short..................

But they all are in the ball park, just that some cases will be off a little if you crimp the bullets per a "Can" on a certain bullet, just pumping the handle on the final die.

With "Mixed cases" one needs to seat to the "Can" then the final step is a crimp............ by "feel".

Good loading.

The difference in length will make a difference in the combustion of the powder. In your case it will be pretty small and you or your father probably won't even notice it unless one or both of you are above average shooters.

Just for future reference, trimming isn't just about getting the brass the same length, it's also about getting the case mouths square. Also the SAAMI recommended dimensions are industry standards and may not apply to your particular firearms.

novalty? How many have you gotten trimmed in 2 years?

__________________
Still Running Against the Wind

May not be a popular notion around here, but in my experience, case length and roll crimping are much over thought. A roll crimp is very "forgiving" and .010" variations in case length won't make any difference in applied crimp. No change in accuracy and although there may be a slight change in velocity, it's insignificant...

I have been going to get a 9mm and 38 cal. trimmer for my Forester for almost ten years now..................I looked up the part numbers and everything.


The only problem is my cases either split, crack or get lost before they are long enough to trim.

I agree with this 100%...for 70-80% of the shooters.

I also, have never trimmed a case in .38's, or any other caliber. Never had any issues. Bob

Never, never ever trimmed a .38 Special case. Don't even own a case trimmer. Don't see a need for one. You're worried about nothing. IF it got to the point that the crimp was off, then yes. BUT, at .002", that's not going to happen.

I've got a lee trimmer set up on my drill press that only takes a few seconds to trim a case (and it's really cheap). With bottleneck cartridges it's a necessity. Because of the ease of using it I have trimmed some straight pistol cases, but I thought it was guilding the lilly.

PS The only reason I do this is mixed brass.

__________________
"He was kinda funny lookin'"

No need to trim a straight wall case. Just a waste of time and effort.

The only time I trim handgun cases is when I convert 9x19 (Luger) to 9x18 (9mm Makarov).

All I use is "range brass" - 1X fired or who knows how many times. I don't trim it, I just load it and use a moderate roll crimp. I'm loading bullets that I have cast myself - RN, WC, SWC. Never been an issue

I use both brass and nickel - I prefer nickel, especially when loading place powder 38 spl. - it's easier to clean up - and it looks "party". LOL

I do have some new Star Line and Winchester brass sitting on the shelf but I probably will never break into it unless I should run short of range brass. In the case of using "new virgin brass" - I'd check them for OAL. I've never checked mine but I have heard from others that they have had to trim to length at times.

As an added note - if you do run across some that need to be trimmed due to small split, etc. - you can trim them back to 38 Colt Long length and load them using data for the 38 Colt Long. The 38 Colt Long was the "parent cartridge" for the 38 Special. Only difference is that it is shorter than the 38 Spl and thus, you'd want to use loading data for that cartridge as smaller case volume = increased pressure. They can be fired out of your 38 Spl.. - no problem. The same as 38 Spl. can be fired in a .357.

I don't trim my handgun cases, but, if one wants to, there is no reason why he shouldn't. There are reloaders who reform primer pockets, some may de-burr flash holes, some weigh each and every case, some sort by headstamp, others may trim their handgun brass, and some go to great lengths to polish their brass to mirror finishes. I don't, but I don't consider any reloading actions a waste of time.

For me and many other reloaders this is a hobby in connection to our shooting, not up for group approval, it's our ammo! If a feller wanted to paint his cases ti--y pink, it's OK by me...

I have 38spl brass once fired factory stuff that measured 1.157" after sizing, I also have once fired factory 38 spl brass that measured 1.142" after sizing. So how would I achieve a consistent crimp with out trimming?

You absolutely won't. That's exactly why I trim my revolver brass to a consistent length. 1.145" for 38 spl.

"You absolutely won't"
That's what I figure, if I need a heavy crimp for 38spl as to help a slower powder burn more efficiently the case length must be close. And then there is the out of square case mouth thing.
I find the same thing with .357 mag. but crimp is even more important. I use RCBS 38spl/357 mag dies which comes with a washer that measures about .125" kinda cool if I trim my brass accordingly I have minimum adjustment between loading these two cartridges.