.357 Magnum reloadiing

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DaggerBlade

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Max OAL for a .357 mag is 1.590". Using a 158grain SWC bullet. If I crimp the case at (A in jpg) OAL is 1.600"-1.610". If I crimp the case at (B in jpg) OAL is 1.590". Crimped at "A" the cylinder will still rotate without rubbing. I have several hundred rounds crimped at "A". I know several guys that reload who crimp at "A" without issue. Is there any risk or issues crimping at "A" or should I crimp at "B"?

http://i280.photobucket.com/albums/kk164/fwwhartonFrank2011CRMGS/158g SWC_zpsag5ief1w.jpeg
 
As long as I am not seeing any high pressure signs and accuracy is good, I don't even measure the OAL of my revolver rounds, beyond making sure that my crimps are consistent. Having looked at the picture, I would crimp in A since that looks to be the crimp groove though.

There are others with more experience but, IMO, it is a non-issue.
 
Most any time it concerns a rimmed cartridge, such as .357 mag., 38 spcl. and the like, as long as we are crimping into the canelure it makes no difference what the resulting measured OAL is. For that matter, it isn't even necessary to measure the OAL on these type cartridges.

Now when it concerns rimless cartridges, 9mm, 45 ACP and the like, yes, we must monitor OAL, thus developing the load up around the OAL that fit and feeds through that firearm.

Hope that satisfies your concerns.

GS
 
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Roll crimp into the crimp groove, that's what it's there for. Welcome to THR

attachment.php
 
It just might depend on your revolver. My GP100 will eat anything up to at least .050" over the max specified OAL, but my SP101 will only go about .020" over max, because its cylinder is shorter (more compact). So, put a completed round (whose OAL you know) into the cylinder, and eyeball or measure how much room there is between the end of the cylinder front edge and the bullet tip. Pressure-wise, there's not much concern unless you use max loads of high-volume powders.
 
Thanks for all the reply. I am shooting a Colt Python. If it is crimped like the round on the right in Walkalong's photo above, the cylinder rotates without issue. Crimped .010 or more further back in the groove and the bullet will rub and the cylinder won't rotate. Just want to make sure I am safe this way. I can buy a new gun but fingers are hard to replace.
 
Usually, having the bullet slighty farther out will actually reduce pressure slightly.

If it doesnt protrude out the front of the cylinder, it should be OK. Some guns, the OAL will matter more than others. Lever action rifles may be more length sensitive, as well as some smaller revolvers.

I dont think I've ever checked actual length on rimmed cartridges, other than seeing if they fit and function in the guns I'm going to use them in.
 
My initial reason for checking case length was because I had some issues at the range. Last time I went to the range, I had a few rounds that were crimped in the groove but towards the base of the bullet and rubbed the barrel preventing cylinder rotation. As long as I stay at the front of the groove I am ok. Just want to be safe.
 
Roll crimp into the crimp groove, that's what it's there for. Welcome to THR
Click to expand...

That is an excellent example photo! I've seen you post it before, and wanted to mention it.



.357 Mags crimped in the crimp groove have a much better chance of the bullet staying in the same place when you get to the 5th and 6th round. OAL in revolvers is only for bullets without cannelures.
 
This is interesting to read, good question OP.

Most any time it concerns a rimmed cartridge, such as .357 mag., 38 spcl. and the like, as long as we are crimping into the canelure it makes no difference what the resulting measured OAL is. For that matter, it isn't even necessary to measure the OAL on these type cartridges.
Click to expand...
Im a very green reloader. Im surprised to hear this, after reading about pressure, etc. I have some LRN 158gr bullets that if crimped at the crimp groove result in a OAL that is a bit shy of the published minimum OAL (guestimate is with crimp in crimp groove, the OAL would be short of min OAL by about .05"). Can this really be ignored, so long as one works up loads from safe starting loads and keeps an eye out for pressure signs?
 
If following proper protocol, which is to always work up the charge from a reasonably safe start charge, there should be no real concern. And again, the canelure / crimp groove has a significant place in the process when it regards this type cartridge, the crimp groove nearly always designates what the OAL will be. There are some exceptions, such as unusually short cylinders, and obscure bullet profiles, that aside, we roll crimp into the canelure / crimp groove.

GS
 
I coulda swore I answered this post/question. Must have been on another forum...:confused:
 
Really? I thought everyone measured rimmed cartridge oal in the begining, I did. But then again, we didn't have the internet when I started reloading, so I had no way of knowing any different. What I do remember is pulling my hair out trying to get the canelure and the oal to correlate, what a nightmare.

GS
 
No internet when I started either.

Started with Lee Loaders. Crimp in the crimp groove, if it fits in the gun and the load is safe, its good to go. When I bought a used Rockchucker Jr press and a mid 70's Speer manual (brand new!), I didnt change much. I dont recall what Speer had to say about cartridge AOL, but I think they mentioned it mattered more in some guns than others, or that some loads were over listed AOL, but functioned in their test gun.

Am reading backwards up the thread, I see you went over that.

I have some LRN 158gr bullets that if crimped at the crimp groove result in a OAL that is a bit shy of the published minimum OAL
Click to expand...

Wait, theres a minimum? I dont recall seeing anything about minimum lengths. That would leave wadcutter loads out of in the cold wastelands of non-spec desolation.
 
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In my friends Windicator he ran into the issue that crimping in the crimp groove on 158 grain SWC they would tie up the cylinder.

When I load SWC for bullseye competition or practice I seat the bullet to point B on your picture, with half of the forward driving band in the case. I apply a very light crimp, basically a taper crimp. Those loads are super light below starting loads though.
 
In my friends Windicator he ran into the issue that crimping in the crimp groove on 158 grain SWC they would tie up the cylinder.
Click to expand...

The question is WHICH 158gr SWC. There are a lot of different molds out there.
 
In the rare instance where crimping into the cannelure or crimp groove doesn't work, we have to make adjustments, but for a general rule crimp into the cannelure or crimp groove and that is the correct OAL for that bullet.

Speer manuals talk about this, and they also list the actual OAL for the bullet used, unlike some manuals or especially website PDFs which often just quote the Max OAL for the caliber.
 
Funny you mention OAL in manuals. In Speer 9 and 10 it never listed OAL for revolvers, and in 9mm, it was in the text describing the round, and not the load tables. :D
 
The only time I cared about OAL was when loading some stout 180 XTP loads with an ample supply of 2400. Otherwise as long as it fits in your chamber and you work up properly you'll be good to go.

Also worth mentioning, my experience has been that the Colts and GP 100s have shorter cylinders than your blackhawks and larger framed smiths. So when loading longer bullets you may need slightly reduced powder charges in the shorter cylinders. But again, as long as you work up properly you'll be plenty safe.
 
gamestalker said:
Really? I thought everyone measured rimmed cartridge oal in the begining, I did. But then again, we didn't have the internet when I started reloading, so I had no way of knowing any different. What I do remember is pulling my hair out trying to get the canelure and the oal to correlate, what a nightmare.

GS
Click to expand...
I kind of had to chuckle at this since I had the opposite experience. I had the internet when I started reloading and have learned immeasurably valuable information from it. Not worrying about OAL in rimmed revolver rounds was one of the first things that RC set me straight on :)

The problem I ran into for the first couple of years was that I found myself getting turned about every couple of days with yet another point of view or opinion piece that got me re-thinking everything.

I am sure that a lot of pre-internet reloaders also had no mentor but, throw the vast amount of good and bad info out there on the internet into the mix and it made my head spin.

I have finally (for the most part) learned how to separate the wheat from the chafe. I have several friends who reload now which helps as well. I am little more qualified to use a lot of that internet info to get pointed in the right direction. Thanks to folks like RC and you, I have saved a lot of time and money.
 
Well if we choose to consider what Billy Bob thinks, then yes, the internet can create a great deal of confusion and misinformation. Other wise, if it existed back in the day, answers would have been so much easier and quicker to figure obtain.

There is no comparison, IMO.

GS
 
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