357 AMP handloading |
Post Reply | Page 123 6> |
Author | |
John Nada
International Auto Mag Joined: 23 Sep 2014 Location: France Status: Offline Points: 222 |
Post Options
Thanks(0)
Posted: 05 Mar 2021 at 3:22am |
Is there any data for Vihta N110 powder for 357AMP. For 44AMP I was told 19.5 grains was working well in someone else gun. (that all the data I found for this powder).
|
|
paul v.
International Auto Mag Joined: 10 Mar 2008 Location: western ny Status: Offline Points: 90 |
Post Options
Thanks(0)
|
This may help.
|
|
Luc V.
Admin Group Joined: 09 Mar 2008 Location: Belgium Status: Offline Points: 1338 |
Post Options
Thanks(0)
|
Luv2shoot, The numbers
on the supervel file are CUP (copper units pressure) to make it even more
difficult there is also LUP (Lead units pressure). Those two terms were used
back in the days, depending on the type of crushers used. One remark
about the conversion formule you found, I would not trust this much because
there are to much different copper crushers used. With each new batch of
proofed crushers you had to be recalculate the whole formule to get the correct
pressure. Back then you could not just read the pressure from a clock on the
test pressuregun. It had to be calculated from the measurements of the crushed
piece of copper. As far as
your 19 grains of H110 it might work well. The reason the slow powders work OK
on much lighter loads as usual is because you used it in a bottle necked case
instead of a straightwall case. I'm pretty sure a to light load would not work well in a straightwall case. I have a
similar result with my 357 Sig caliber. Because you
have to push all that volume of burning powder throug a smaller diameter the
pressure will rise (due to the shoulder in the shell) before the bullet leave
the shell, not the barrel. Difficult to explain in words, but try this to
understand: take a waterhose and sqeeze it off to a smaller diameter you will
see that it will spray water much further because of the rised pressure. If you
sqeeze it even more tighter you might burst the hose (if enough water pressure
to start with.) I hope this makes you understand somehow the way pressure
works... To get back
to your 19 grains load, to make it work well and consistent, make sure you have
a verry good grip of the bullet in the case. The use of a factory crimp die (I
use Lee Presicion) is recomended. If the bullet has to little grip in the case
the primer can have enough force to push the bullet foreward before a good
ignition of the powder. Then you should find much unburned powder in the
barrel. If it burn well and have a clean barrel, you a probably good to
go. About a
case not completely filled with slow burning powder, it fails because there is
to much room (airspace) inside the case and primer has enough force to blow the
powder foreward and the flame is to cold to short for good ignition. I doubt it
it could happen in a 357AMP case with 19 grains H110. Thats why I said to use
magnum primers. In all my
reloading experiments I had that happen once with a very light load in 45-70
Gvt cartridge. I worked well when I switched to magnum primers. It all
sound difficult, but its just logic....
I would suggest to load 20 or 30 rounds and try them but also look good for accuracy, if they are consistent and good groups, it will work fine. If you have fliers all over the target the pressure (ignition) is not reliable you should adjust the load.
|
|
BEEMER1
Callahan's Auto Mag Joined: 06 Jan 2010 Location: iowa Status: Offline Points: 1307 |
Post Options
Thanks(0)
|
As far as 19 grains being as low as one should I guess that all depends on the gun. I was told to start there and work up until I found a load that would lock the bolt back and met my accuracy expectations. Both 19 and 20 did that in my gun so I stayed at 19.
The springs in my gun probably need changed and after putting in Wolff +10% springs I am sure I would need to go up. good luck.
|
|
Luvz2Shoot
Callahan's Auto Mag Joined: 16 Apr 2011 Location: Washington Status: Offline Points: 618 |
Post Options
Thanks(0)
|
Beemer: About 15 years ago, not too long after I got my first 357AMP, I was at a gun show and on one of the tables a guy had a small plastic bag with shells in it. Written on the bag was "40CT. 357 Auto Mag. $5". Needless to say I couldn't get a $5 dollar bill out of my pocket fast enough. When I got home I checked each shell in my gun. Each shell allowed the bolt to close and rotate into the locked position. Right then I knew I got lucky running across these. Starting this reloading process I started with a different 357 barrel but used those shells as a starting point. I locked the bolt open and dropped a shell into the chamber. Very slowly I closed the bolt and it only "hung up" when the extractor went over the rim of the shell. Once the shell was against the bolt face I closed it all the way and it rotated and locked into place. I knew that those shells would give me a good starting point at seating the shoulder depth.I set the shell in my 357 necking die and ran the die down to the point that it just touched the shoulder. I backed the die off about 1/2 of a turn. I ran the first 44AMP shell into the neck die. I then put it in the gun to see if the bolt would close and lock into place. (the first time did not). Then I turned the die down a little and ran the shell again to neck it just a little further. Again, I checked for fit. After about 4 or 5 minor turns of the die I got the neck down far enough to fit into my chamber - but it was tight! So, I took the die and turned it down a hair more. The shell dropped in and the bolt was able to close and rotate into the locked position. I then did the "test" that Tim Bell posted in another thread. With shell in the barrel and the bolt close and locked on it, take the end of the barrel and push it into a towel and watch the travel. I observed how far the barrel moved before the bolt started to unlock and rotate. I guessed that with very little "play" before the bolt started to disengage, I got the shell to rest on the bolt face where it is supposed to, and that I had gotten the shoulder fit for my gun correct. I ran a bunch of 44 shells to that neck depth. I verified that each shell dropped in and checked the "barrel push check" on every shell. I was assuming that I got everything correct every step BEFORE loading with any powder. Before dropping powder into the first shell I had read everything that I could. I must have put a good 10-15 hours into reading, searching, and posting on here. This has been fun and I can't wait to start loading a few hundred rounds for the 158gr bullets. THEN I'll start to work on some hole-punching loads for the 125gr bullets. I plan to start at Lee's lowest suggested load (LOL). And I will go back through and see what other "recipes" people have shared for the 125gr bullets. Luc: Thank you for posting this. I noticed they are testing 24gr of 296. WOW! In the "pressure" column, do you think that is PSI or CUP pressures? I found this conversion online: CUP to PSI: (PSI + 17902)/1.516 = CUP PSI to CUP: (1.516 x CUP) - 17902 = PSI By your numbers (above) that you got from your program, I am only right around 24569 CUP. (19345 + 17902) / 1.516 = 24569. As Beemer and you have mentioned/hinted, for this gun 19gr of H110 (or W296) should be right around the very lightest we should be using? |
|
If you were happy and you knew it, would you clap your hands?
|
|
Luc V.
Admin Group Joined: 09 Mar 2008 Location: Belgium Status: Offline Points: 1338 |
Post Options
Thanks(0)
|
If I remember well, I have an email from the late Lee where we discussed pressure in automag cartridges and he said that he usually worked around the maximum of 50.000 CUPs. for the 44
I guess the 357 should be much the same. Included is an old file about tests he did for the 357. |
|
BEEMER1
Callahan's Auto Mag Joined: 06 Jan 2010 Location: iowa Status: Offline Points: 1307 |
Post Options
Thanks(0)
|
Luc, you are probably right and I was aware of that when I posted the comment. I do not remember if I read that or Lee told me that and I do not know where to look for it. All I know is that Jurras tested some Lomont AMP loads and the were well into pressures that are normally only seen in magnum rifles. Jurras said they were well beyond anything he would load. Luv2shoot - I understand your concerns. I will say this, after 30+ years of hand loading I could not come up with a worse cartridge to start on than the 357 AMP. With head spacing concerns, reformed brass, and user unfriendly powders it is a tough one for anyone. When I bought my first 357 AMP it came from a girl and it included 2 boxes of ammo from a commercial reloader. There were only two rounds fired out of the 40 which I found strange. I loaded one round and fired it and everything went fine. I loaded two rounds next and the gun would not fire as it was not in battery. I started checking the ammo and nearly all had the shoulder too far forward to chamber. I checked my gun against the dies and the headspace on my pistol was out of spec and I had to remove material from the bottom of the die to reload for it. When loading for Auto Mags caution is advised.
|
|
Luc V.
Admin Group Joined: 09 Mar 2008 Location: Belgium Status: Offline Points: 1338 |
Post Options
Thanks(0)
|
To Luv2shoot, it's easy to know the volume of the resized case, just pour water in the case and fill it to the top. That weight in grains is the maximum volume.
To beemer, I'm almost sure Lee Jurras never tested the Automag cartridges in PSI. Back then all testing was done in CUP. There is a Huge difference between the two. It's a mistake often made to mix those numbers/parameters. |
|
BEEMER1
Callahan's Auto Mag Joined: 06 Jan 2010 Location: iowa Status: Offline Points: 1307 |
Post Options
Thanks(0)
|
Lee Jurras tested some of Kent Lomont's loads in his pressure barrels at Super Vel and he had loads for the 44 and 357 AMP at 65,000 psi. Glad it was not me or my gun doing the shooting.
|
|
Luvz2Shoot
Callahan's Auto Mag Joined: 16 Apr 2011 Location: Washington Status: Offline Points: 618 |
Post Options
Thanks(0)
|
Luc,
Thank you for the info and the offer. I am not an experienced loader either. In fact this was the first time that I have loaded for anything. I figured that if I can meticulously go through the process to load my 357AMP, I can apply it to just bout anything else that I shoot (and feel fairly comfortable doing so). I do have to say that after firing off the 19gr load and seeing what the gun did, I just can't imagine loading it any higher. After reading everyone's input, I see that it can go higher. Thank you for running the info through your program. I have no idea what the volume of the case is, but I can see what I can find. I am trying to load these things exactly as published by Lee and other sources. I am loading with CCI 350 Magnum pistol primers. (I do remember reading to only use magnum primers when loading for these.) Does anyone know what sort of pressures these things can be loaded up to? I thought i remember reading that Lee and Kent were testing/shooting these pushing 30,000 CUP? |
|
If you were happy and you knew it, would you clap your hands?
|
|
Post Reply | Page 123 6> |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |