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jdavionic
09-15-2012, 11:35
First, I'll preface by saying I try to get my competition loads near my carry loads. Not to say that I'm knocking those that aim to be slightly above the min required PF. Different folks compete for different reasons...which is great. The more that compete for whatever reason, the better.

All rounds fired from a G19. Temperature at the range was 74F.

124 gr MG PHP
Titegroup 4.1g
Avg OAL 1.117
Avg vel 1107 fps

124 gr Ranier PHP
Titegroup 4.1g
Avg OAL 1.127
Avg vel 1100 fps

124 gr Ranier PHP
Titegroup 3.9g
Avg OAL 1.127
Avg vel 1054 fps

Hornady CD 115g FTX
Avg OAL 1.078
Avg vel 1151 fps

Federal Hydra Shock 124g
Avg OAL 1.055
*Avg vel 1011 fps
* Note - data includes 1 round that was obviously low pressure. Made an alarming low sound. I examined the spent case and didn't see anything unusual. The velocity of that round was only 721 fps.

Question -
My standard dev on velocity was around 14 fps on the 3.9g data. The SDEV was close to that on my other reloads. Is that typical for you?

F106 Fan
09-15-2012, 12:11
Question -
My standard dev on velocity was around 14 fps on the 3.9g data. The SDEV was close to that on my other reloads. Is that typical for you?

Sometimes better, sometimes worse. I have a 6.5x284 Norma load that has a SD of 6.1. Velocity is 2660 to 2676 fps. The stuff shoots pretty well.

I have some pistol loads with single digit SDs but the funny thing is that I don't care about the pistol loads. I just want the average velocity to make some arbitrary and meaningless power factor. I don't compete so such things don't really matter.

The rifle loads I do care about. I haven't gone completely around the bend on trying to obtain uniformity but I'm considering it.

Richard

Colorado4Wheel
09-15-2012, 12:48
I usually get SD in the single digits when I work it up to my better loads

WiskyT
09-15-2012, 13:16
My SD's with pistol loads are usually around 20. I used mixed brass and that makes a big difference as every round has different neck tension. Obviously I don't care.

jdavionic
09-15-2012, 13:34
My SD's with pistol loads are usually around 20. I used mixed brass and that makes a big difference as every round has different neck tension. Obviously I don't care.

I used mixed brass as well.

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fredj338
09-16-2012, 00:13
My SD's with pistol loads are usually around 20. I used mixed brass and that makes a big difference as every round has different neck tension. Obviously I don't care.

^^THIS^^
The only way, if it even matters, to get single dig SD is to load same manuf brass fired the same number of times. It also helps to use a faster powder or slower powders w/ compressed chargers. Case neck tension is the driving part of that though. It really only matters to the gamers trying toget their ammo to just over min PF. It really has little to no affect on psitol ammo shot under 25yds.

shotgunred
09-16-2012, 08:38
First, I'll preface by saying I try to get my competition loads near my carry loads. Not to say that I'm knocking those that aim to be slightly above the min required PF. Different folks compete for different reasons...which is great. The more that compete for whatever reason, the better.

124 gr MG PHP
Titegroup 4.1g
Avg OAL 1.117
Avg vel 1107 fps

124 gr Ranier PHP
Titegroup 4.1g
Avg OAL 1.127
Avg vel 1100 fps

124 gr Ranier PHP
Titegroup 3.9g
Avg OAL 1.127
Avg vel 1054 fps

Hornady CD 115g FTX
Avg OAL 1.078
Avg vel 1151 fps

Federal Hydra Shock 124g
Avg OAL 1.055
*Avg vel 1011 fps


You are not straying very far from "gamer loads". The most common one I am aware of is 4.1 TG with a 124g at 1.135 OAL chronos at 1100-1110 range. Personaly I fell that pushing the 9mm 124 to 130 -135 pf range give you more accurate ammo.

dla
09-16-2012, 09:12
How many shots did you do for the SD?

jdavionic
09-16-2012, 11:38
How many shots did you do for the SD?

10 shots per load type