Do I shoot them?

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AzDanMan

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If the COL I want to load is 1.125 and some of come out 1.115 - 1.120. Are they safe to shoot?
It's 9 mm mixed brass using 3.2 gr of Accurate #2 with 125 grain TC bullet.
 
Use your kinetic hammer and lightly knock the projectile out a little and then reset the bullet to the proper length.
Are you using all the same bullets?
We're you adjusting the seater depth when you got these different length pieces of ammo?
Applying different amounts of pressure on the handle when seating the bullets?

Personally I would not shoot them.
Let's see what others have to say.
Good luck & be safe.
 
If the COL I want to load is 1.125 and some of come out 1.115 - 1.120. Are they safe to shoot?

9 mm mixed brass using 3.2 gr of Accurate #2 with 125 grain TC bullet.
https://www.accuratepowder.com/wp-content/uploads/2011/01/accurate_load_data_3.5.pdf
  • 9mm 124 gr LC Lead RN No 2 COL 1.050" Start 3.0 gr (895 fps) - Max 3.8 gr (1,012 fps)
  • 9mm 124 gr BRY HBFP No 2 COL 1.060" Start 3.3 gr (881 fps) - Max 4.1 gr (999 fps)
  • 9mm 124 gr RAN HP No 2 COL 1.110" Start 3.3 gr (885 fps) - Max 4.2 gr (1,001 fps)
I think you should be fine. Because bullet weight can vary by 1.0+ gr, I often interchange 124/125 gr load data with 124/125 gr bullets.

With 3.2 gr of No 2 and 125 gr lead TC bullet at 1.115"-1.120", you are slightly above lead start charge of 3.0 gr.
 
@AzDanMan, welcome to THR!

Assuming your goal of 1.125” COL is a good working length in your gun(s), and the OAL of your bullet while TC is close to RN, you’re just above start charge weight but still quite a bit longer than the published COL. If it were me, and this was load development, I’d shoot them but note their length and respective V. If the the load has already been established, I’d have a better idea of how a shorter COL would perform. But given your information and the published data, I’d shoot them. I’d also be investigating my process to see what is going on. Good luck.
 
What shape is your seating stem...?
A flat stem would prolly get 'em more consistent,
Whereas as stem for a roundnose could touch the TC in different places.
Personally, I don't see much of an issue with .005"-.010" myself and would shoot them.....
 
If the COL I want to load is 1.125 and some of come out 1.115 - 1.120. Are they safe to shoot?
It's 9 mm mixed brass using 3.2 gr of Accurate #2 with 125 grain TC bullet.
Did you do a plunk test to find out the COL for you barrel? If not that should have been the first thing you should have done. As mentioned in another post you need to find out why you are seeing a difference in the COL on the cartridges you have loaded. Mixed brass will not affect the COL. If some brass is longer and some is shorter it will affect the amount of the bullet seated in the brass but will not affect the COL if you have everything set up correctly.
 
PV = nRT

n, R, and T are constant. PV is a simple relationship. Super simplistic analysis here but ask yourself how much does 0.005-0.010” change it? Bullet casting has variations depending on cavities and seating dies can have dirt buildup.

Measure the case depth under the seated bullet. Assume 0.500” for example (I have no idea what yours actually without measuring my own loads). Potentially a 2% variation in this example. If a max load I would analyze the risk based on slow or fast burn rate. MAP is max avg pressure. This risk is likely within a +P envelope.

Measure your own case and bullet combination and check the math briefly.

Personally I would shoot it, but note 9mm is more sensitive to pressure spikes due to fast powder burn rate, small case capacity, and high pressure.

Your hands, face, and wallet up to you.
 
Your variance is not extraordinary for mixed brass loaded on a progressive. If they plunk, I'd send 'em. Just take a brass rod to the range with you;-) PS: Tighten up your shell plate, adjust it with a case in each station, and make sure you're using the correct seating stem profile for TC. I mean really though, you're talking about thousandths here, and all within the book data. I think you worry for naught. If you were loading for a match on single stage, with identical head stamp brass, or new brass, maybe I'd want to see what's going on, but other than that, if it plunks, it sends.
 
Thanks everyone for your comments. I loaded these on a Lee Turret press with the Lee 4 die set. The seating stem is for round nose, I checked to see if I could flip it but cannot.
I am shooting these out of a Shadow 2 and 1.125 plunk very well. I guess I should look into a different seating die.
Again thank you for you help.
 
Use your kinetic hammer and lightly knock the projectile out a little and then reset the bullet to the proper length.
Are you using all the same bullets?
We're you adjusting the seater depth when you got these different length pieces of ammo?
Applying different amounts of pressure on the handle when seating the bullets?

Personally I would not shoot them.
Let's see what others have to say.
Good luck & be safe.

I did do as you said and they measured back the same as before. I used the same amount of pressure as the rest that came out good.
 
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