What am I doing wrong?

Melnibonean

Melnibonean

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Evening all,

I just chronographed my new pistol loads, and I came up with some disturbing numbers and I don't know why.

I'm using W231, both Federal and Win primers and loading to the mid-way point between min and max charge as per an average of 3 reloading manuals (Lyman, Speer, Hornady)

For 9mm 147 gr, I'm gettting fps of about 5xx-6xx. COAL is within spec
For .45ACP 230gr, I'm getting fps of about 3xx-4xx. COAL is within spec as well.

At first I thought it was my chrony, but I immediately followed up the pistol shots with some rounds from my reloads in .223 (55 gr FMJ) and .308 (150gr FMJ) and they were in the sweet spot, so I know the chrony is working fine.

If the chrony is fine, and the poweder weight is within the min/max range, might it be I need a tighter crimp? Or am I missing something? I'm using the Dillon 650 and Dillon dies.
 
I just got a chrony and tested my .45ACP re-loads against some Blazer factory...the Blazer ammo clocked at an average of 771 FPS and my re-loads at 632 FPS. I am using 4.7 grains of Unique and a 230 grain round nose hard cast bullet. I prefer the mild loads for an old (1917) Colt 1911 that I have and they are good for plinking.
How much W231 are you using in your .45ACP loads???
 
Skinny 1950 said:
IHow much W231 are you using in your .45ACP loads???
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Ganderite said:
What guns? What barrel length? What powder charge? jacketed or lead?
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For the 9mm, I'm using 3.8gr of W231 under 147gr FMJ Zeros. The gun is a CZ Shadow. Barrel length is 4.70"
For the .45ACP, I'm using 5.3gr of W231 under 230gr FMJ Zeros. The gun is a M&P45. Barrel length is 4.50"
 
EDIT: So here are the speeds from the chrony. The specs are as I've already listed.....

9mm
563, 540, 569, 546, 560 = average of 555 FPS. Books say I should be between 850-900 FPS or so

45ACP
349, 307, 332, 286, 313 = average of 317 FPS. Books say I should be between between 800-840 FPS or so
 
The W231 is listed as somewhat faster burning than Unique so I can't see how your loads are slower using more powder. One possibility that I thought of revolves around your powder scale...what type of scale are you using and is it known to be accurate???
 
Do people calibrate their scales? I check mine regular. i shoot titegroup using 4.1 gr and 124 gr. Campro in a 5" bbl. they run a minimim 1030 fps.

I use a Dillon 550.
 
Ganderite said:
You are right. 5+ gr of 231 should be faster than that in 45. According to my scales, a dime weighs 27.8 gr. Yours?
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Not a reliable standard. I weighed 4 dimes of different years with these results on both my RCBS 5-0-2 scale and my Hornady Electronic scale:-

1999 - 31.9gr
2003 - 27.6gr
2009 - 26.8gr
2010 - 27.0gr

(Yeah, there's always one in every crowd, I know... <g>) At any rate, I suspect what others are suspecting....Assuming that the chrony is accurate, the OP's powder scale is way, way off and dangerously so.
I'd suggest placing one of the 147gr bullets on the scale and see what it reads.
 
cycle a few rounds through your press, then pull one out that has a charge in it. dump that on the scale. I'm thinking you've got inconsistantcy in the amount of powder being dropped.
With my 550, I check that I am getting consistant powder every so often. I found that when I changed powders i could get the weight i was looking for, but the next one would be off a bit. Now I am set with titegroup, and leave it alone.
 
I pulled a few bullet in both calibers and weighed the projectiles. The Dillon balance beam scale is reading the correct weight for the projectile.

I used that same scale to weigh out the charges to use in reloading both my .223 and .308 which were averaging 2782 and 2747 fps respectively out of my AR and Norinco shorty, so I'm pretty confident that the scale is working fine if those two calibers were coming in where they were supposed to.

I then did as hoochie suggesteda and cycled a few rounds through the press, assuming either my Dillon powder measuring unit was off AND the low powder warning sensor was also off and not detecting a too little thrown charge, and it threw 3.8 and 5.3 respectively (I only have to swap the toolheads out on the 650, saving me the time to re-calibrate the powder dispenser). I usually measure the charge of every 15th round or so to be sure that I'm not over/under charging the round anyways.

Could it be I'm creating too big of a bell at the case mouth and it's not sealing fully up against the projectiles at the crimp station (light as that crimp should be)? I'll try and put up some pics later of the shells coming out of station #2 for you all to have a look.
 
Chronographs don't like sub sonic loads, particles of powder get to the screen before the bullet, and can result in a false reading. Try putting a paper or cardboard baffle in front of the chronograph and see if your readings change. You might as well eliminate that variable right out of the gate.
 
Boomer said:
Chronographs don't like sub sonic loads, particles of powder get to the screen before the bullet, and can result in a false reading. Try putting a paper or cardboard baffle in front of the chronograph and see if your readings change. You might as well eliminate that variable right out of the gate.
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I will try this. Hadn't known about this phenomena.
daBear said:
Are you chrony'ing under flourescent lights? They are notorious for false readings..
dB
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No, I bought the light fixtures that attach to the diffusers from Chrony just so I could use it indoors. Like I said, the rifle rounds were chronoing fine indoors.
 
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