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357 and 44 AMP chronograph fun

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Pantera Mike View Drop Down
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    Posted: 15 Jun 2019 at 1:12am
I just got a chronograph and was interested to see how my 357 and 44 AMP handloads were doing, and also compare my 44 loads to SBR factory ammo.

Today, I was shooting 44 AMP with 240gr Hornady XTP bullets, Starline cases, WLP primers, and WW-296 powder, and using SBR ammo as a control measure. 

I fired three, five-shot strings with SBR, with the following average results:

1400
1395
1391

I then turned to my reloads. I purposely started near the lower end of the recommended loads (using Hornady data), and found they were all too light to cycle the action properly. Every round resulted in a short stroke, and either a jam (failure to feed with the round stuck halfway out of the magazine) or a dry fire, as it failed to pick up the next round at all. In any case, here are the results:

20.5 — 1166
21.0 — 1192
21.5 — 1220
22.0 — 1246
22.5 — 1289

Only once using 22.5 grains, the action cycled properly. Clearly I will have to turn up the steam.  The max published load is 23.8 grains. I’m confident I will have success with 23.0-23.5 grains.  Time to head back to the loading bench. 

I also shot 357 Auto Mag with 158 Gr Hornady XTP bullets, Starline cases, WLP primers, and WW-296 powder, with both 6.5 and 8.5-inch barrels. Here are average results:

6.5-inch:

21.5 — 1632
22.0 — 1631
22.5 — 1686

8.5-inch:

22.0 — 1770
22.5 — 1788

The extra two inches of barrel length delivers an additional 100-150 FPS, not as significant as I expected. Functioning was flawless with 100% reliability with both guns. I have generally had much better luck with the 357 AMP than 44 AMP, for various unknown reasons.....

Today was also the first time I fired my Smith and Wesson Model 27 N-frame revolver, rechambered for 357/44 Bain and Davis. The B&D is philosophically similar to 357 AMP, formed my necking down 44 Magnum cases to accept a 357 bullet. 

I used old Hornady data with the expectation that I would not get to go all the way up to their max load, since their data was tested in and intended for the T/C Contender. I was using new Midway cases, WLP primers and WW-296 powder, with Hornady 158gr XTP bullets, and my Model 27 has a 6.5-inch barrel. The average velocity for five-shot strings was:

20.0 — 1469
20.5 — 1485
21.0 — 1472
21.5 — 1546
22.0 — 1552
22.5 — 1585

I started getting adverse pressure indications at 22.5, in the form of slightly flattened primers and difficult case extraction, so I stopped there although I had loaded rounds through 24.0 (24.9 was max published). 

It is very fun to shoot, although one could make the case that similar results could be achieved more easily by simply ignoring published 357 Magnum data and overloading those cases, to bring them up to 1935-era pressures and performance. I suspect if you were to find a box of 357 Magnum factory ammo from the late 1930s it would deliver similar performance to the B&D, but these days the cartridge has been downloaded due to the preponderance of revolvers having smaller, lighter frames.  The max load for 357 Magnum using 296 in the Hornady book is 1250 FPS.

Now that I know where the limits are, I will likely brew up a few batches of 21.5 and 22.0 and shoot for accuracy next time. I have a feeling it will be very effective. 

The Auto Mag gets about 75-100 FPS more than the B&D with the same load and barrel length, likely due to the lack of the barrel/chamber gap. Barrel length is slightly misleading because automatic barrels include the chamber as part of the barrel length.  So the 6.5 inch Auto Mag barrel is really more like 5 inches of actual barrel. 

Fun stuff!
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AndyC View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote AndyC Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jun 2019 at 5:19pm
Mike, your 22.5gr at 1289 is only 11 fps off my average (using H110, same as W296):


Some went a little higher, some lower - I'm blaming the Hornady electronic powder-heaver for this (although I'm pretty sure I have something to do with it) ;)

My 6.5 TDE does cycle and lock at 22.5, even though I put in new Wolff recoil-springs (.200") in it before testing.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Auto Mag Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jun 2019 at 5:36pm
My "generic" 44 AMP load for over 20 years has been a Hornady 240 gr XTP over 23.5 gr of WW 296 in a CDM or Norma case with a CCI-350 primer.

It works well in most guns and is both accurate and powerful enough for medium game or for shooting pins or plates.

Its not flame thrower and not a 44 Special.

I always keep some of this load on hand, and for many years it has proven to be a good universal 44 AMP load in guns that are in good mechanical shape and have reasonable/proper tolerances. 

Broken or lunchbox guns are a whole separate problem, and in my experiencing no load will fix those guns, thats a mechanical problem. 

GH
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BEEMER1 Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jun 2019 at 6:53pm
SBR is loading 23.5 grains of H110/296 in their 240 grain loads.
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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: 16 Jun 2019 at 6:58pm
Originally posted by BEEMER1 BEEMER1 wrote:

SBR is loading 23.5 grains of H110/296 in their 240 grain loads.

That’s very helpful info. I will brew up a batch of 23.0 and see what happens, and step up to 23.5 if needed.....

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Auto Mag Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jun 2019 at 7:37pm
23 - 23.5 gr is a modest load, when you hit 25 gr you need to be careful, the gun needs to be right and you are starting to get into the true high performance firearms zone. 

A 240 gr bullet over 25 gr of WW 296 will sizzle.  Expect some impressive chrono numbers!

And if you really want to make some thunder, try a 180 gr XTP over say 30 gr of WW 296.  Fair warning, your gun better be in perfect condition and you better have your ammo loaded right. This is a load that you need to respect.

Do not attempt this unless you are certain your gun is up to snuff and you know what you are doing.

You have been warned.

GH
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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: 16 Jun 2019 at 11:59pm
FWIW the Hornady Manual lists 23.5 as max for H110 and 23.8 for 296 (even though they are the same powder). I just want to achieve proper functioning.  The piece of paper I’m shooting at won’t know the difference if I get another 50-100 FPS from a higher-than-max loaf, and I don’t feel like having broken Auto Mag parts raining down on me.  I’m a ‘color inside the lines’ guy when it comes to reloading.....
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Auto Mag Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jun 2019 at 1:07am
Originally posted by Pantera Mike Pantera Mike wrote:

FWIW the Hornady Manual lists 23.5 as max for H110 and 23.8 for 296 (even though they are the same powder). I just want to achieve proper functioning.  The piece of paper I’m shooting at won’t know the difference if I get another 50-100 FPS from a higher-than-max loaf, and I don’t feel like having broken Auto Mag parts raining down on me.  I’m a ‘color inside the lines’ guy when it comes to reloading.....

Coloring inside the lines is a good thing when it comes to loading ammo, but that then that begs the question, who drew the lines and did they know what they were doing.

I would not advocate you start out with Jurras or Lomont loading specs, but Hornady is by no means the expert on what is a max load for the Auto Mag.

If minimal function (as opposed to "proper") then stick to the minimum load that works the gun all the time.  No sense in wasting expensive powder on paper,,, Pins, plates and game are a different story.

ATB

GH

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Post Options Post Options   Thanks (0) Thanks(0)   Quote edkel1 Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jun 2019 at 1:11am
I am looking forward to reloading some .357 and trying it out but i'm not in a rush , I finally took out my .44 AM today and was pleasantly surprised Big smile Yes it was fun is an understatement.
Thanks for all the info on the .357
Ed
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