can i skip case trimming on .38spl

[Dan Cash]

If you use a roll crimp (which you should if you are loading up to factory velocity or greater) then you should trim (as needed). A fresh batch of cases should be checked for length and trimmed to minimum stated length. Any "growth" in excess of a couple thousandths of an inch you should trim again. If not it will change the consistency in the release of the bullet and accuracy will be affected. I did a test one time years ago. I loaded some .38's with random fired brass of unknown origin. Didn't measure case length, but hand weighed each powder charge, and hand primed every case and checked overall length for consistency. Then I loaded a batch of all the same brand once fired cases, carefully trimmed to exactly the same length, and loaded exactly as I had the previous batch. I fired each batch separately in a custom tuned Mod 19, 6", mounted in a Ransom Rest at 50 ft. The carefully trimmed batch turned in a 10 shot group of under a half inch. The non trimmed batch 10 shot group was 1 1/4".

So, If you are satisfied with the level of accuracy you get with not trimming, don't trim. If you want the best accuracy trim.

I won't argue the results of your testing. I will say that it is meaningless when the handgun is no longer in the Ransom Rest but is hand held. The hand held firing platform is unable to exploit the precision of the ammunition and for most applications, the effort to achieve that precision is totally wasted.

 

[ISOM]

No crimping .38 Specials

I have been reloading since August 1970.
About 20 + or - years ago I ran into a deal of 5 Taper Crimp dies for $25.00. Since then I Taper Crimp EVERYTHING!

To get a generic Taper Crimp die, all you need to is remove the decapping stim from your sizing die. The readjust it for crimping.

 

[lmcgust]

The PPC Masters and Grand Masters in our league don't trim their .38 special brass. That's good enough for me.

BR,

Guy -

 

[Jellybean]

I won't argue the results of your testing. I will say that it is meaningless when the handgun is no longer in the Ransom Rest but is hand held. The hand held firing platform is unable to exploit the precision of the ammunition and for most applications, the effort to achieve that precision is totally wasted.

I disagree, the mechanical device removes the human error and shows the ammunitions true accuracy potential. When handheld, the inaccuracy of the ammunition is added on to whatever human error is present, so a group shot with 1" ammo that shot to 3" would shoot to 4" with 2" ammo.

The problem is that human error is not only due to inconsistencies, but the inconsistencies are inconsistent also. Meaning that the 1" ammo above may shoot into a 3" group once, then 4", 5" and 6" and possibly even 2". Trying to work up an accuracy load while holding the gun offhand is a waste of time because you are adding too many variables, and this can even happen while shooting off a bench.

 

[Paul5388]

Beaner old boy, you seem to be forgetting how everyone can shoot 1" 25 yard groups off hand and they do it with boring regularity with +P+ loads.

 

[Jellybean]

Paul, for some reason your post reminded me of the time I agreed to help score targets for a big PPC match. I never made that mistake a second time.

 

[NKJ nut]

Beaner old boy, you seem to be forgetting how everyone can shoot 1" 25 yard groups off hand and they do it with boring regularity with +P+ loads.

Almost everyone. You forgot about me

 

[BE Mike]

If you use a roll crimp (which you should if you are loading up to factory velocity or greater) then you should trim (as needed). A fresh batch of cases should be checked for length and trimmed to minimum stated length. Any "growth" in excess of a couple thousandths of an inch you should trim again. If not it will change the consistency in the release of the bullet and accuracy will be affected. I did a test one time years ago. I loaded some .38's with random fired brass of unknown origin. Didn't measure case length, but hand weighed each powder charge, and hand primed every case and checked overall length for consistency. Then I loaded a batch of all the same brand once fired cases, carefully trimmed to exactly the same length, and loaded exactly as I had the previous batch. I fired each batch separately in a custom tuned Mod 19, 6", mounted in a Ransom Rest at 50 ft. The carefully trimmed batch turned in a 10 shot group of under a half inch. The non trimmed batch 10 shot group was 1 1/4".

So, If you are satisfied with the level of accuracy you get with not trimming, don't trim. If you want the best accuracy trim.

Did you do your accuracy tests at 50 feet as stated, or did you mean 50 yards?