Would you/ should I?

[showmebob]

After trimming all my 357 mag cases I reset my dies for a slight roll crimp. I am using Berry's plated bullets that probably should have a taper crimp instead of a roll crimp. I don't want to over crimp heeding a warning about cutting through the plating and causing a possible separation. Yesterday at the range I measured a round and placed it in the #5 position. I then shot the first 4 and removed #5 and remeasured it. I did this 3 times with the following results. All COL's shortened, two by .010.

On my 9mm I am using Berry's plated bullets with a taper crimp. I followed the same procedure that I used for the 357 except the measured round was placed in #17 position. The results were the measured round COL's lengthened by as much as .006.

While I'm not as concerned about COL lengthening as shortening, my question is. Would you/should I increase the crimp? Or is this something I will have to live with with Berry's bullets?

 

[The Bushmaster]

Calling rc and Walkalong...Where are you?

 

[rcmodel]

Got me baffled!
I was waiting for you or Walkalong to answer that one!

Revolver rounds getting Shorter due to recoil has to be against the laws of physics!

Auto pistol rounds getting battered in the bottom of a magazine growing Longer falls under the same classification.

Could be a left-hand thread dial caliper?

rc

 

[The Bushmaster]

And how about the roll crimp for plated bullets?

 

[rcmodel]

Berry says:
http://www.berrysmfg.com/faq.aspx?q=14&c=1

http://www.berrysmfg.com/faq.aspx?q=13&c=1

I would roll crimp for revolvers and taper crimp for autos.
Just don't over-do it.

But either style of crimp cannot make up for improper neck-tension to start with.

Check the expander plug and turn it down .001" - .002" if necessary to get good neck tension.

rc

 

[ReloaderFred]

As noted, the neck tension alone should do most of the work in keeping the bullet in place, with the crimp being a backup. For .38 Special, I use a roll crimp for plated bullets, and also for .357 Magnum. I just back off the crimp until I feel it's right and I've never had a problem with them.

For 9x19, I taper crimp plated bullets in place, but I also depend on neck tension to do most of the holding.

Hope this helps.

Fred

 

[showmebob]

I am using a RCBS 3 die set for the 357 and Lee 4 die set for the 9mm. Is there any way to increase the neck tension using these dies?

 

[rcmodel]

Chuck the RCBS expander plug, or through-powder expander stem in the case of the Lee in a drill, and work it down with a strip of fine emory cloth.

rc

 

[Walkalong]

I use a light to medium, and occasionally a bit heavier taper crimp on plated bullets in .38/.357.

I have tried roll crimps, even light ones over the front of plated 148 Gr DEWC's without success. Fred and rc must be a better crimper than I am.

For 9MM I use a light taper crimp, like jacketed and lead.

Could be a left-hand thread dial caliper?

That's gotta be it.

 

[Gewehr98]

Trimming .38 Spl and .357 Magnum cases?

That energy would best be spent doing something more productive.

 

[Walkalong]

But I just love trimming cases.

 

[The Bushmaster]

AND if you want consistent crimp from one cartridge to another you better trim those .38 Special and .357 magnum cases to within +/- .002 of each other....

 

[showmebob]

Gewehr98
Senior Member



Join Date: 12-24-02
Posts: 5,876 Trimming .38 Spl and .357 Magnum cases?

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That energy would best be spent doing something more productive.
__________________
While I'm certainly no expert I beg to disagree. Before trimming the cases the short ones would not crimp and the long ones way over crimped to the point of buckling one case to the point it would not fit in the cylinder. Since trimming every case crimps the same.

 

[showmebob]

AND if you want consistent crimp from one cartridge to another you better trim those .38 Special and .357 magnum cases to within +/- .002 of each other....

Bushmaster
All 1147 cases are just that......AND......I love trimming cases.

 

[showmebob]

"Could be a left-hand thread dial caliper?"

Sorry, don't think so. Even my wife agrees with me on this one!!!!!

 

[ReloaderFred]

I think I'm going to box up about 15,000 rounds of .38 brass and ship it to all you guys who "love trimming". That should keep you busy for awhile, and since I'm such a nice guy, I'll pay the shipping both ways.............

If you do a good job, I'll send about 5,000 rounds of .357 brass, and then about 20,000 rounds +/- of .45 acp brass...........

Fred

 

[kestak]

Greetings,

Roll crimp on plated bullets can be bad. If it cuts throught the plating, you can end up with part of the plating separating from the bullet.

I just read yesterday that a guy shooting 500 plated bullets got a piece of plating stuck in his barrel and thanks God, he noticed the difference in shooting and looked into his barrel.

I use just enough crimp in my auto calibers to prevent the bullet to be pushed in the case while it reloads.

In my revolver calibers, I use just enough crimp so the recoil does not make the bullets move. With the 44mag it is a lot of crimp. With the 357mag, it is a lot less. ;-)

Thank you

Thank you

 

[Walkalong]

box up about 15,000 rounds of .38 brass and ship it to all you guys who "love trimming". That should keep you busy for awhile

No thanks Fred, very thoughtful of you though.

I haven't done the 500 I traded for. I just finally trimmed the range brass I have been working loads up in to finalize some good ones. One of these days.

I have been taper crimping most of them, and that is much more forgiving than a roll crimp.

 

[MMCSRET]

Only one supposition left. Take three steps to the left, you are obviously shooting from a location of intensified gravitational pull!!!!!

 

[The Bushmaster]

O K Fred...Now simmer down...Don't get carried away in the moment. I didn't say I really enjoyed trimming cases. It's just (as you know) part of the over all enjoyment of reloading. Now lower your head before you drown. I know it's raining over there.

 

[ReloaderFred]

Actually Bushmaster, it snowed here on the coast yesterday. Must be that global warming thing they keep talking about.... This is about the 4th snow this year, and we hardly ever get snow.......

I still don't trim straight wall pistol cases, and probably never will. Even when I was shooting PPC, which includes shooting at 50 yards, I never trimmed .38 cases.

The volume that I load would preclude trimming, as I don't think I've got enough years left on this earth to trim the buckets full of brass I have on hand right now.

Walkalong, those brass may grow, since they were in a damp environment here and I'm sure you're in a damp one back there. I've already worn out the brass I got from you......

Fred

 

[Gewehr98]

I don't either.

I don't trim straight-wall pistol cases, or straight-wall rifle cases.

Over the last 25+ years I haven't had any problems with roll/taper crimp attributable to varying straight-wall case length. I figure that's probably well over 20K rounds fired and reloaded, in 9mm Luger, 9mm Steyr, .38 Special, .357 Magnum, .44 Special, .45 ACP, and .45-70, at a minimum. My IPSC/USPSA/PPC/Steel Challenge time was sucked up in either cranking the Dillon lever, or shooting. Trimming straight-wall pistol brass - seriously?

Bottleneck pistol and rifle, hell, yeah! They get trimmed if they don't fit the case length gage, and after a couple trimmings, they get checked for a stretch ring.

There's an old joke about .45 ACP brass being like Mexican women - the older they get, the shorter and wider they become.