Unable to crimp 38-40 cases after trimming them to trim to length

M

mrappe

New member
I have been loading 38-40 for 22 years using a Redding FL die set. I was shooting an original Winchester 1873 with a 24" barrel in that caliber up until a 1 1/2 years ago when I bought a Uberti 73 from Taylors with a 20" barrel in 38-40. I found that when I when I loaded 10 rnds (the max that we ever load for a stage) into it some of the bullets would get pushed back into the case. This never happened with my older gun which had a longer mag and an old spring so I realized that the rnds needed a firmer crimp and finally started seating the bullets with the Redding die and crimping them with a Lee Factory Crimp Die. This was working and I bought some new Starline brass and measured it. It was way longer than the max length so I trimmed it to the recommended length of 1.295" and loaded it but I saw that the crimp was not enough either with the Lee die or the Redding built in roll crimp. Under pressure the bullets could get pushed into the case. I measured my old brass and found that it was around 1.32" to 1.34" in length and over the published max length of 1.305". I have not measured or trimmed the cases in a long time and did not have any problems chambrering them in either gun. The problem seems to be that when I trimmed the new cases to the published spec I cannot get a good crimp on them due to the length of the brass even if I set the dies down to where they touch the shell holder at its peak. Someone said at my club that I should shorten the die but I don't have a lathe to do that so I am trying if all of the brands of the dies are going to have the same problem. It seems like the dies would be made so that you could roll crimp even when the brass is trimmed to the trim to length.

thanks,

Mike
 
I load .44 WCF, another fussy round.
What bullet are you using,does it have a crimp groove?
Have you shortened the magazine spring?
I had a die shortened , they are hard stuff it took a tool post grinder on the lathe.
 
You may be able to remove a touch of the top surface of the shell holder, by hand, using a grinding wheel. Take care to keep it square. I have done this with good results.
 
It wont due any harm to use a bench grinder on the crimp die. First :

I am curious, have you measured the case length on new once fired factory ammo? You might be in for a surprise. if not, at least it would be a sanity test. Cause something dont sound quite right here. BOTH - the new brass and the dies - I suspect pilot error.
 
As mentioned above, SAAMI length is 1.305MAX - 1.295MIN (not necessarily the recommended overall length)

Still... I'm having a hard time seeing a standard RCBS standard roll crimp die being unable to accommodate that.
What bullet are you using?
 
I had a 45-70 seat-crimp die shortened to use on my 1876 45-60 by a local gunsmith for 10.00, a lot cheaper than a set of 45-60 dies. I would have that done on your seat-crimp die.
 
Simple fix, sick your crimping die in a lathe and cut off a few thousands from the base.

I've dont that to many of 357 crimping dies people mistakenly bought to load 38s.

Cut it as short as you need it. You can always screw the die out a little if need be to crimp longer cases.
 
Well I found out what caused this. I was looking at my dial calipers and noticed that when completely closed the dial was showing 0.04 which meant that I measured my new brass a being too long and consequently trimmed it too short. It was too short to reach the crimp inside the die. My calipers are old and cheap so I could not reset it so I just bought a new digital one and remeasured everything. I am not sure when the old one got off but from now I will always check the zero. Now I am stuck with 100 rnds of new too short brass that I cannot use. Lesson Learned and I am glad that I had not trimmed my older brass yet because when I measured it with the new calipers it is setting at the right length even though some of them have been reloaded for more than 20 years.

Thanks,
Mike
 
you could use the short case for your first shot as they would not need a crimp. or as just a practice round at the range, single feeding them.
 
Try another brand of shell holder, they are not all the same thickness or remove metal from the top of your shell holder...the shell holder is not hardened steel (the die might be hardened) and it's the cheapest part....just in case it gets messed up.

I don't care what the book says the "trim to" length is.... Experience has taught me 1.31 or 1.305 is the shortest you want to go.
Taking .015" or .020" off the top of your shell holder should put you back in business.
Good luck,
Gary
 
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