November 14, 2009, 09:35 PM | #1 |
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first time 9mm load
I am a reloading newby and had some questions with a load that I am working on, 9mm using 122 gr TC lead bullets.
1) Everywhere I have looked 124 gr is the closest weight I have seen to 122 gr. Can I use the starting load for the 124 gr since it is a little less than what the 122 gr should use? I would be using 5.6 grs of Power Pistol, Wolf SPP and Winchester brass. 2) From what I have found in my books and online max COAL is 1.169 and the min is 1.000. The best max COAL I can get using these 122 gr bullets is 1.056 which just covers the lube with the case. Should I be safe if I seat midways between the lube and the base of the cone, approx. 1.037 using the starting load above or will I risk too high of a pressure? This leads to my 3rd question. 3) When the manuals show starting loads do they use min COAL or max? To me it makes more sense to use min COAL because everything else up to max COAL would be safe because of lower pressures. |
November 14, 2009, 11:46 PM | #2 |
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122 gr.9mm
I looked at Loadata.com for you and the only thing I could find close was for Unique powder. 122gr. cast lead and 5.2gr. of Unique. And Unique is listed as #35, Power Pistol #39 on the Burn Rate Chart.(fastest-slowest). So you,re right there. I have found this web to be a lot of help to me, check it out. And good luck, hope this helps! Good loading.
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November 15, 2009, 11:37 AM | #3 |
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The Cartridge Over All Length (COAL) or alternatively, the Over All Length (OAL) will differ only from one bullet style to another. It does not change as you decrease or increase the powder charge. Nor does it change, if you change powders.
The maximum COAL is the length at which the majority of chambers will accept, assuming the gun is built to SAAMI specs. Hence the minimum length. The length you get, is determined by the length of your case plus the length of the bullet after seating. This can and will differ from one bullet style to the next. Since you will be using a TC (Truncated Cone) style bullet, you will be seating this bullet so that the case mouth is somewhere on the band just above the lubrication groove. Note: If your cases are of different lengths, then your seated bullet may be off a few thousandths, regardless of your COAL. If this bothers you, or the case mouth extends above that last band (or worse, into the lubrication groove), trim your cases to the same length. My Lyman's (48th) data shows a minimum charge of power pistol to be 5.1gr and a maximum at 5.7gr for a 120gr TC bullet. The only other data I can find is with a 125gr gas checked bullet, that has a starting point of 4.8gr and a max of 5.4 gr. Based solely on that, your starting point of 5.6gr of power pistol is already at or above the max load. I would suggest that you back off 10% and work up from that point. |
November 15, 2009, 01:58 PM | #4 | |
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Quote:
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November 15, 2009, 02:26 PM | #5 |
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Yes.
I have been told by many reloaders to never confuse load data for jacketed bullets with lead bullets. Always look for data of the same type: Lead to lead and jacketed to jacketed. |
November 15, 2009, 03:50 PM | #6 |
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Maybe it's clear to you from the responses you have received, but for a starting point, you should use the COAL of the load you are using. The range you listed does exist in various manuals, but to use a shorter length than the load was developed with, can result it a dangerously high pressure.
I also understand you are having problems finding "your" bullet. Using a load for 125 grain lead (slightly heavier) would be the conservative thing to do. It is better to use a load listed with a heavier bullet than you are using, than to use a lighter bullet. Best is to find the same.... |
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