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 Post subject: Crimp
PostPosted: Sun Feb 11, 2018 6:43 am 
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Joined: Fri Oct 01, 2010 6:43 am
Posts: 241
Location: Sydney, Australia
I have a Walther GSP-C in .32SWL. I reload using HBWC swaged pills. It has been my practice to leave a smidgen of lead proud of the case mouth and to use a light roll crimp.

All good.

I acquired a TOZ 49 revolver that had been converted to the same calibre, i.e. .32SWL.

I found that my cartridges, loaded as before, would not "chamber" properly in the TOZ. It has to be understood that the TOZ has a particular action which, on cocking the single action hammer, moves the cylinder forward to insert the nose of the round into the forcing cone so that on ignition there is a gas seal to prevent leakage between cylinder and frame.

I found that using a significant taper crimp (using a Lee taper crimp die) overcame this problem and the rounds now feed OK.

Using these taper crimped rounds in the GSP-C does nor appear to be a problem.

My question is: am I significantly effecting the performance of my .32SWL HBWC rounds sticking with a taper crimp for both pistols or should I find a taper crimp option which works with both pistols?

I guess really the question is: what differences in performance do the two types of crimp make?

Bob


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 Post subject: Re: Crimp
PostPosted: Sun Feb 11, 2018 6:55 am 
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Joined: Wed Feb 23, 2011 3:07 am
Posts: 48
Bob,
I have a Toz 49 with original 7.62 x 26 chambering.

I trim my cases to 25.60, and load to o/a 27.20, giving approx. 1.5mm of lead exposure. An o/a longer than this will cause jamming of the cylinder when cocking.
I have tried various taper and roll crimps, and have found that a moderate roll crimp gives the best results. This could be a starting point, with any variations subject to testing in a machine rest.
I used a similar loading style with my .32 with excellent results.

Hope this helps.
Max.


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 Post subject: Re: Crimp
PostPosted: Mon Feb 12, 2018 9:20 pm 
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Joined: Mon Jul 07, 2008 4:04 am
Posts: 534
Location: Sydney, Australia
madmax wrote:
Bob,
I have a Toz 49 with original 7.62 x 26 chambering.

I trim my cases to 25.60, and load to o/a 27.20, giving approx. 1.5mm of lead exposure. An o/a longer than this will cause jamming of the cylinder when cocking.
I have tried various taper and roll crimps, and have found that a moderate roll crimp gives the best results. This could be a starting point, with any variations subject to testing in a machine rest.
I used a similar loading style with my .32 with excellent results.

Hope this helps.
Max.


Hi Max, which brand die do you use to get a roll crimp on a TOZ 49 case? ( 7.62 Nagant short )


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 Post subject: Re: Crimp
PostPosted: Mon Feb 12, 2018 9:52 pm 
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Joined: Thu Jan 24, 2008 5:55 pm
Posts: 865
Location: Australia
I find what works well in my TOZ 49 is to seat the hbwc level with the case mouth and then apply a miniscule crimp.

This way of reloading also works very well in my Manurhin revolver and accuracy is almost identical.

I hope this is helpful.


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 Post subject: Re: Crimp
PostPosted: Wed Feb 14, 2018 7:51 am 
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Joined: Mon Sep 16, 2013 6:31 am
Posts: 58
[quote="deadeyedick"]I find what works well in my TOZ 49 is to seat the hbwc level with the case mouth and then apply a miniscule crimp.

This is how the russian factory ammunition looks. I have never shot in chronograph, but I am told the good ones do 190m/s.


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 Post subject: Re: Crimp
PostPosted: Wed Feb 14, 2018 3:29 pm 
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Joined: Wed Feb 23, 2011 3:07 am
Posts: 48
Hi Leon,
I use a relatively new set of Simplex dies for reforming / decapping and seating / crimping. I find the flaring die to be too savage - angle too steep, resulting in case mouth splitting. For flaring I use a Lee Universal Case Expanding Die, and apply only enough expansion to allow the projectile to begin insertion. These Simplex dies are a little different to the older ones.
Hi JD,
Using 1.8 WST, my velocities are just over 200mps.

Max.


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 Post subject: Re: Crimp
PostPosted: Tue Feb 20, 2018 4:38 pm 
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Joined: Mon Jul 07, 2008 4:04 am
Posts: 534
Location: Sydney, Australia
Thanks Max - I also have a set of Simplex, but with a Simplex taper crimp die. I did not know that they also offer a roll crimp one, or can the taper crimp also produce a roll crimp.


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 Post subject: Re: Crimp
PostPosted: Tue Feb 20, 2018 4:39 pm 
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Joined: Mon Jul 07, 2008 4:04 am
Posts: 534
Location: Sydney, Australia
Thanks Max - I also have a set of Simplex die set, but with a Simplex taper crimp die. I did not know that they also offer a roll crimp one, or can the taper crimp also produce a roll crimp?


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 Post subject: Re: Crimp
PostPosted: Wed Feb 21, 2018 5:18 am 
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Joined: Fri Oct 01, 2010 6:43 am
Posts: 241
Location: Sydney, Australia
Thanks all, I guess my problem is the .32SWL conversion. The forcing cone may be a bit "under reamed".

Trimming the cases should help but it is a pain to do that for a large number of cases. However, needs must, and once done, etc. etc.

I load a .314 swaged pill but had to disassemble 3-5 rounds when I realised I was using unprimed cases! I measured the diameters of the unloaded pills (these were the taper crimped ones) and found that the diameters had been reduced to the .310 region vs. .314 original diameter. Now, I don't know if propelling the bullet out of the case rather than driving it out with a bullet puller would result in less slimming down but I think I need to find a minimal crimp solution.

Bob


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 Post subject: Re: Crimp
PostPosted: Wed Feb 21, 2018 3:31 pm 
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Joined: Wed Feb 23, 2011 3:07 am
Posts: 48
Hi Leon,

My Simplex dies produce a roll crimp.
They have '988' on the head.

Max.


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