5.7 reloading

ADIDAS69 · October 17, 2016, 04:49 AM

I have read a number of older threads that suggest reloading 5.7 is problematic and possibly dangerous. I am wondering if there is an update to proper process and safest practice especially regarding the proprietary coating on the shell casing. Any information would be appreciated.

darkgael · October 17, 2016, 05:30 AM

AFAIK there is no news about the process of reloading the little beast.
The "difficulties" are two in number. The first is that the range of powder charge weight from minimum to maximum is very small, only six or seven tenths of a grain. There are only three propellants for which there is published data...Accurate #5 and 7, Ramshot True Blue.
Proper resizing presents the other problem. Firing the 5.7 blows the shoulder of the case forward more than any That I have ever seen (and I load more than forty different cartridges). Setting the shoulder back requires that the press be set to "cam over" - at least my Rockchucker does.
This process works the neck and shoulder enough that case separations can and do occur. Normally, annealing the neck would solve the problem but these cases cannot be annesled because of the polymer coating.

ADIDAS69 · October 17, 2016, 11:28 AM

Yeah sounds like everything I've heard or read. It's a shame, I picked an AR lower from Sharps Brothers that has a skull milled on top of the mag well. I was hoping to use one of the available 5.7 uppers resulting in brass falling out of the skull. Much sadness.

T. O'Heir · October 17, 2016, 12:50 PM

Read this. https://www.loaddata.com/articles/PD...arce%20LR1.pdf
And this. http://www.fivesevenforum.com/w/inde...itle=Reloading
Biggest issue is there's no brass available if you need it. Neither Midway nor Graf's list any. Some on Gunbroker though.
These guys want $40 for 500 pcs. No idea how old the page is.
https://www.diamondkbrass.com/5.7x28-MM-500.html

RC20 · October 18, 2016, 05:54 PM

Point of order if you will and veering off 5.7 topic but definitely reloading.

Anneal is aimed at maintaining the neck area good, but that's case splits and neck tension uniformity.

Case separation occurs down at the base (1/4 way up) - ergo the should push back and minimal doing so.

That's the wisdom and my experience. could be wrong.

The 5.7 may break up there, but I never had any other case do that (split yes). They must have a way out head space (reliability?, large chamber?)

All my case separation (mostly with FC) have been down at the base.

darkgael · October 19, 2016, 06:14 AM

RC: You are correct about the normal use of the terminology....Case separations most frequently occur at the web or a bit above it.
My experience with the 5.7, though, is that the neck does not split....there is a complete separation at or slightly above the shoulder. The neck remains in the chamber and prevents the following round from chambering. I attribute that to metal fatigue. Perhaps I am wrong....I wish, though, that I had a few cases to show just how much the shoulder blows forward upon firing. There is a lot of metal moving both upon firing and again at resizing. I am careful about headspace....measuring cases and setting dies. What I have found, though, is that the sizing die will not set the shoulder back far enough unless the ram over cams.
Suggestions welcome.

darkgael · October 23, 2016, 01:03 PM

Here is a pic showing two once fired cases next to a factory round. Note the shoulders.

October 17, 2016, 04:49 AM	#1
ADIDAS69 Senior Member Join Date: October 17, 2009 Location: Seattle Posts: 381	5.7 reloading I have read a number of older threads that suggest reloading 5.7 is problematic and possibly dangerous. I am wondering if there is an update to proper process and safest practice especially regarding the proprietary coating on the shell casing. Any information would be appreciated. __________________ "...I would walk with my people if I could find them..."

October 17, 2016, 05:30 AM	#2
darkgael Senior Member Join Date: February 9, 2006 Location: Homes in Brooklyn, NY and in Pennsylvania. Posts: 5,473	5.7 AFAIK there is no news about the process of reloading the little beast. The "difficulties" are two in number. The first is that the range of powder charge weight from minimum to maximum is very small, only six or seven tenths of a grain. There are only three propellants for which there is published data...Accurate #5 and 7, Ramshot True Blue. Proper resizing presents the other problem. Firing the 5.7 blows the shoulder of the case forward more than any That I have ever seen (and I load more than forty different cartridges). Setting the shoulder back requires that the press be set to "cam over" - at least my Rockchucker does. This process works the neck and shoulder enough that case separations can and do occur. Normally, annealing the neck would solve the problem but these cases cannot be annesled because of the polymer coating. __________________ “Auto racing, bull fighting, and mountain climbing are the only real sports ... all others are games.” Ernest Hemingway ... NRA Life Member

October 17, 2016, 11:28 AM	#3
ADIDAS69 Senior Member Join Date: October 17, 2009 Location: Seattle Posts: 381	Thanks Darkgael Yeah sounds like everything I've heard or read. It's a shame, I picked an AR lower from Sharps Brothers that has a skull milled on top of the mag well. I was hoping to use one of the available 5.7 uppers resulting in brass falling out of the skull. Much sadness. __________________ "...I would walk with my people if I could find them..."

October 17, 2016, 12:50 PM	#4
T. O'Heir Senior Member Join Date: February 13, 2002 Location: Canada Posts: 12,453	Read this. https://www.loaddata.com/articles/PD...arce%20LR1.pdf And this. http://www.fivesevenforum.com/w/inde...itle=Reloading Biggest issue is there's no brass available if you need it. Neither Midway nor Graf's list any. Some on Gunbroker though. These guys want $40 for 500 pcs. No idea how old the page is. https://www.diamondkbrass.com/5.7x28-MM-500.html __________________ Spelling and grammar count!

October 19, 2016, 06:14 AM	#6
darkgael Senior Member Join Date: February 9, 2006 Location: Homes in Brooklyn, NY and in Pennsylvania. Posts: 5,473	OK RC: You are correct about the normal use of the terminology....Case separations most frequently occur at the web or a bit above it. My experience with the 5.7, though, is that the neck does not split....there is a complete separation at or slightly above the shoulder. The neck remains in the chamber and prevents the following round from chambering. I attribute that to metal fatigue. Perhaps I am wrong....I wish, though, that I had a few cases to show just how much the shoulder blows forward upon firing. There is a lot of metal moving both upon firing and again at resizing. I am careful about headspace....measuring cases and setting dies. What I have found, though, is that the sizing die will not set the shoulder back far enough unless the ram over cams. Suggestions welcome. __________________ “Auto racing, bull fighting, and mountain climbing are the only real sports ... all others are games.” Ernest Hemingway ... NRA Life Member

October 18, 2016, 05:54 PM	#5
RC20 Senior Member Join Date: April 10, 2008 Location: Alaska Posts: 7,014	Point of order if you will and veering off 5.7 topic but definitely reloading. Anneal is aimed at maintaining the neck area good, but that's case splits and neck tension uniformity. Case separation occurs down at the base (1/4 way up) - ergo the should push back and minimal doing so. That's the wisdom and my experience. could be wrong. The 5.7 may break up there, but I never had any other case do that (split yes). They must have a way out head space (reliability?, large chamber?) All my case separation (mostly with FC) have been down at the base.

October 23, 2016, 01:03 PM	#7
darkgael Senior Member Join Date: February 9, 2006 Location: Homes in Brooklyn, NY and in Pennsylvania. Posts: 5,473	Shoulder Here is a pic showing two once fired cases next to a factory round. Note the shoulders. __________________ “Auto racing, bull fighting, and mountain climbing are the only real sports ... all others are games.” Ernest Hemingway ... NRA Life Member