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Starting over questions

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sparksh View Drop Down
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    Posted: 09 Jun 2019 at 11:58pm
I'm a beginner and new to the forum. There's a lot of information to distill and digest.

A week ago, I dragged down my Auto Mag 357 from the closet where it was stored for about 40 years. After brushing out the foam, the gun appears to be in perfect condition. Another box contained my old Bonanza (now Forster) press, die sets and other reloading tools.

There were two boxes of used brass, spent primers still installed. I made them from rifle brass with the RCBS case forming set. Some are stamped Win 270 and others Win 243. Back in the day, I got lessons from an expert, but I've forgotten all the details.

Thanks to this forum and lots of other resources on the web, I've learned more than I ever knew back then. But reading all this stuff and measuring my old brass has left me more confused than ever.

I visited a big sporting goods store and did some impulse shopping:
  1.  A brass cleaning rig.
  2.  A jar of Hodgdon H110
  3.  A box of CCI 350 primers
  4.  A box of Hornady "XTP" 38 Cal 140 grain bullets
  5.  A bottle of gun oil
  6.  A small bag of Hornady Win 243 brass
The store clerk brought me the XTP when I asked for something near 137 grain. It is, he explained, a devastating round for large animals. I told him I only wanted to devastate sheets of paper and minimize wear and tear on the gun. In any case, that's all they had so I bought a small box.

No one at the store had ever heard of special stainless steel gun oil. Sadly, I lost the original bottle that came with the gun. I cleaned and oiled following the user manual. Is there a favored modern oil here? What else should I check before firing?

Now I hear that all right-thinking people use Starline 44 AMP brass, but I thought I might be able to try the gun this weekend and I wanted to see if I could make the process work better. My past experience wasn't too good: Frequent feed problems. No doubt I didn't know enough about reloading and I never attempted to "tune" the gun.

I read up on loads and decided that 22 grains of H-110 might operate the gun and not blow me up. Too late, I notice that the bullet box says "Recommended muzzle velocity 700 to 1500 fps." The Speer reloading guide says 22 grains of H110 will produce 1627 fps. 23 grains => 1706 fps. I can't return the bullets. Should I try them or buy something else?

I discovered that my case forming reamer was more-or-less wrecked. I found it loose in the cardboard storage box and it had a patina of rust. After cleaning, it works more like a smooth rod with ribs. It can't be sharpened on a tool and cutter grinder because of the shank=cutting diameter expected by the reaming die. The cutting diameter appears to be 0.376 (Is that right?) The only replacement I could find with a shank=cutter size is a solid carbide tool for over $100.  Any ideas about where to buy the correct reamer? I see someone here used a 9mm reamer = 0.353". That seems way off, but I don't really know what the correct size should be.

I have the Bonanza/Forster case trimming tool and amazingly they still support the product. Now you can buy internal reaming and external neck turning accessories for this tool. They offer custom sizes at a reasonable price, but I don't know what the right dimensions would be without the case stuffed into a reaming die. That's not how these cutters are normally used. It this a reasonable idea?

Could someone comment on the correct O.D. and I.D. at the neck end of the case? The old AMP drawing shows 0.382 and 0.0357 which implies a wall thickness of .0125. All my old (quite possibly wrong) brass has a wall thickness of 0.015.

Thanks for any and all suggestions!


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edkel1 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote edkel1 Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 12:17am
Welcome
I too am new, well I  guess 11 weeks new.
The only thing I can recommend would be the oil to use on a SS gun, FP-10 and I asked this very question when I bought my Auto Mags and had no idea, you can get it on Amazon or eBay, as far as cases  use Srarline brass, I have been picking up everything needed to reload but have not started yet but hope too soon.
Others will speak up that can help you out on any needs or questions you may have.
All I can add is read and ask questions.
Good luck
Ed
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sparksh View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sparksh Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 2:49am
They have FP-10 locally. It's a good start. Thanks!

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Pantera Mike View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pantera Mike Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 4:00am
I can’t help you with questions on forming 357 AMP from rifle brass, but it sure sounds like hard work. 

I just used Starline 44 AMP brass, no reaming required.  Running it through the forming/sizing die makes it grow to 1.308 inches which is too long, so it needs to be trimmed to 1.298 max. Kent Lomont advised trimming to 1.294 and never trimming again.  I think I trimmed to 1.295.

I use 158gr XTP bullets with 22.5gr WW296 or H110 (they are identical). I have been advised that lighter bullets beat up the gun unnecessarily, and it has been suggested to me that I would be better off using 180 gr XTP, but I can’t find any load data for bullets greater than 158gr and don’t feel like experimenting that much to come up with data on my own. 

Here is a link to a PDF of Speer reloading data for 357 AMP:


Lee Jurras recommended taper crimping instead of roll crimping. 357 AMP die sets only come with a roll crimp seater die, but it’s possible to find taper crimp dies so you can seat and crimp in separate operations. 

(full disclosure—I have a CH4D taper crimp die for sale as I recently got a second TC crimp die from RCBS as part of a big die purchase, so I have some self-interest in promoting the idea of using a taper crimp die)

I use FP-10 oil in most places, and RIG stainless steel gun grease between the bolt and cocking piece, and around the accelerator. 

You will love the 357 AMP. Once you work the bugs out, it’s a magnificent cartridge! Welcome back to the fold!
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Rocketthon View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rocketthon Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 11:34am
Remember that reliability with an AMP is also dependent on how firm you hold the gun when firing.  If you do not have strong wrists it will be more difficult to get the gun to function real reliable, something I have to remind my son about when we go shooting with either the 44 or 357.

About making brass, all my 44 is formed 7.62 blank, it really makes you work to get them neck reamed and not worth it now that we have a good supp,y of Starline.  I used all Starline 44 when making my 357 and would recommend not looking back.

On loads, never had much trouble with 140 grain bullets beating up the gun, and XTP works fine for target.  Your load of 22 grains of H110 sounds pretty close to mine and if you get the gun loosened up shooting with a firm hand should work.

Were you able to clean out the inside of the cocking piece where the rotate spring is, that is notorious about the lube gunning up and causing jambs.
When you are up to your neck in alligators it is hard to remember your original intention was to drain the swamp
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omie01 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote omie01 Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 1:10pm
The best advise I got about forming .357 AMP, is to disassemble the top end of the gun, use the loose bolt to tell you when the shoulder on the brass will "just" let the bolt close and lock fully and set your resizing die right there, now it is set for your chamber. The reason there was never any reliable .357 AMP ammo commercially was because most .357 AMPs have slightly different chambers. so it's best to set your sizing die to your chamber. Starline brass really is the way to go. And Lee Jurras once told me to roll and taper crimp my rounds, but a roll crimp will work until you find a taper crimp die. I use only 158gr bullets because they seem to cycle my gun well, and seem the most accurate, although you may have a different experience. Good luck and have fun!!
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TRX302 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote TRX302 Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 1:33pm
Originally posted by Pantera Mike Pantera Mike wrote:

Lee Jurras recommended taper crimping instead of roll crimping.


I used to shoot a lot of .357 Magnum, and moved from a roll crimp to a taper crimp. The loaded rounds shot just the same, but I got more loads out of the taper crimp before I started seeing cracks in the case mouth.

Revolver guys are tightwads. "Shoot .357 brass until they crack, then cut them down to .38 Special, and pass them on to someone shooting .38 Short Colt when they crack again..."
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sparksh View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sparksh Quote  Post ReplyReply Direct Link To This Post Posted: 10 Jun 2019 at 6:46pm
Thanks to everyone who replied, I've seen the light and ordered a bag of Starline brass today.

Pantera Mike: The Speer data is reassuring. The loads discussed in the article by George Nonte in Handloader Jan 1975 made me worry that 22 grains might not push the bullet out of the bore. He liked 26 or 27 grains of H110 for a 137 grain bullet and stated that 22 grains wouldn't cycle the action properly.

My next box of bullets will 158 grain, but I went ahead and loaded a small batch of my old brass with the 140 grain bullets and 22 grains H110.

I did the bolt-fit test suggested omie01 with an empty case and went one step further by making the shoulder too high and then reducing gradually until the bolt would rotate. (I found that test in an old post here by Luvz2Shoot in 2011)

Lacking experience, I'm not perfectly confident about what "just right" feels like. I have to push firmly on the bolt to latch the extractor and then more firmly to compress the ejector so the case is against the bolt. THEN I can rotate bolt. It feels slightly rough.

I locked the ring on the sizing die and made up seven cases from 243 rifle brass. They all pass the "bolt test." I haven't fired anything yet. (Busy with work.)

I have another question:

The hole in the case forming die in the neck area is 0.391". When I form a new case, the O.D. in the neck area comes out 0.392: It springs out a little. The wall thickness at the mouth is 0.015 and after using the reaming die, it's 0.015 all the way back into the case.

(I hate this reamer. It wasn't much fun when it was new. I tried boring a few on the lathe to get the same wall thickness. They test concentric. Is that a bad idea?)

There is a well-known drawing of the assembled 357 AMP case and bullet that shows all the dimensions. The O.D. at the neck is supposed to be .382 and the O.D. of the bullet is 0.357. The implied wall thickness is (.382-.357)/2 = 0.0125". But my wall thickness comes out 0.015 and the O.D. at the neck after installing a bullet is 0.387. How on earth does anyone end up with the O.D. shown on the drawing? (0.382) It doesn't add up...

Maybe my dies are wrong? They can't be worn out. Maybe my reamer was never right. If it left a wall thickness of 0.12 it would be more believable.

If someone has a known-good piece of empty brass around, it would be nice to know the wall thickness in the neck area. And what do you guys have for the neck diameter of a loaded round?

Thanks again!

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