[jgedmond]

I loaded up 2 weights each of Tite Group and Power Pistol using either 124gr. MG CMJ or Rem FMJ. Then I shot 5 round groups using my USP9f. Since I am a beginning shooter, I took the best 3 out of 5 shots to judge accuracy. (All loads with WIN brass, CCI500, and OAL of 1.147" (MG) or 1.150" (Rem).)

What I learned: MG CMJ are more accurate than Rem FMJ, MG is not sensitive to PP load (4.8 or 5.2 gr.), MG is very sensitive to TG load (3.8 or 4.2 gr.), Rem is sensitive to powder load for both powders, and PP more accurate than TG.

The last conclusion surprised me. Could this be a function of the gun or did I not shoot enough to get a good sample?

This post has been edited by jgedmond: 28 September 2009 - 06:45 PM

[GrumpyOne]

I don't think a powder affects accuracy so much, more of how the gun reacts, I.E. muzzle flip, rise, felt recoil, etc. Were you using a rest? If so, at what distance? Did you chrono the loads?

[toddrod]

GrumpyOne, on Sep 28 2009, 08:59 PM, said:

I don't think a powder affects accuracy so much, more of how the gun reacts, I.E. muzzle flip, rise, felt recoil, etc. Were you using a rest? If so, at what distance? Did you chrono the loads?

I tend to disagree with this statement. With all the loads that I have tested using a Ransom Rest, there is significant differences between accuracy using different powders. Just to give an example. My 1911 Springield 9mm. Using American Select my best groups at 25yds were 3 inches, change to powder to Titegroup and I got 3/4" groupings at 25 yds. these are just 2 examples. Ihave tested well over a 100 different load combinations in my gun and I have a friend who has even more data for his guns that show the powder makes a big difference.

[GrumpyOne]

toddrod, on Sep 28 2009, 10:51 PM, said:

GrumpyOne, on Sep 28 2009, 08:59 PM, said:

I don't think a powder affects accuracy so much, more of how the gun reacts, I.E. muzzle flip, rise, felt recoil, etc. Were you using a rest? If so, at what distance? Did you chrono the loads?

I tend to disagree with this statement. With all the loads that I have tested using a Ransom Rest, there is significant differences between accuracy using different powders. Just to give an example. My 1911 Springield 9mm. Using American Select my best groups at 25yds were 3 inches, change to powder to Titegroup and I got 3/4" groupings at 25 yds. these are just 2 examples. Ihave tested well over a 100 different load combinations in my gun and I have a friend who has even more data for his guns that show the powder makes a big difference.

I didn't mean to imply that it had no bearing on accuracy, just not as much as implied in most cases. In your case, did you chrono each load? Was each load running about the same FPS? Same bullet? Same OAL? Bullet weight, length, hollow base, flat base, etc. all have a bearing on accuracy, probably more so than most powders would. Even the difference of .003 inches in OAL will affect accuracy (more than likely, you won't be able to tell though!). Just think of the variation in the same powder from lot to lot. While I may not have tested "hundreds" of loads ( I see no reason to test many loads, find something you like, stick with it), through 20lbs of Power Pistol, 8lbs of Longshot and 16lbs of VVN105, I see little to no variation in accuracy, only how the gun reacts to the gases and felt recoil.

[toddrod]

The example I gave was with the same bullet at the same OAL. The only difference I made was to use 8 different powders and just change the charge weights.

I do admit that the accuracy level most shooters are looking for in USPSA is not as exacting as what I am looking for. I was just stating that powder does and can play an important role in accuracy. The only reason I test so much is because I work shift work and have lots of time on my hands. So, I spend that time making loads and testing.

[toddrod]

jgedmond, on Sep 28 2009, 08:44 PM, said:

I loaded up 2 weights each of Tite Group and Power Pistol using either 124gr. MG CMJ or Rem FMJ. Then I shot 5 round groups using my USP9f. Since I am a beginning shooter, I took the best 3 out of 5 shots to judge accuracy. (All loads with WIN brass, CCI500, and OAL of 1.147" (MG) or 1.150" (Rem).)

What I learned: MG CMJ are more accurate than Rem FMJ, MG is not sensitive to PP load (4.8 or 5.2 gr.), MG is very sensitive to TG load (3.8 or 4.2 gr.), Rem is sensitive to powder load for both powders, and PP more accurate than TG.

The last conclusion surprised me. Could this be a function of the gun or did I not shoot enough to get a good sample?

From what I have seen, Power Pistol in in the upper ranges of the suggested load data does make some accurate loads. The Montana gold 124g HP is the bullet I use and the one that I get 3/4" groups from.

[revchuck]

Quote

MG CMJ are more accurate than Rem FMJ, MG is not sensitive to PP load (4.8 or 5.2 gr.), MG is very sensitive to TG load (3.8 or 4.2 gr.), Rem is sensitive to powder load for both powders, and PP more accurate than TG.

Jim - That's way too small a sample to make generalizations about. As you load more, you'll find that overall length, velocity, and charge weight can make as much or more difference as powder or bullet type. If you're taking three out of five rounds in one group as an indicator of accuracy, there's way too much chance of shooter error - believe me, I know about shooter error! - in a sample size that small.

I don't mean to sound like I'm coming down on you about this. You're heading in the right direction as far as load development is concerned. Just do some more testing, checking how variables like overall length affect accuracy and velocity, before you decide on which bullet to stick with.

[jgedmond]

revchuck, on Sep 29 2009, 06:44 AM, said:

Quote

MG CMJ are more accurate than Rem FMJ, MG is not sensitive to PP load (4.8 or 5.2 gr.), MG is very sensitive to TG load (3.8 or 4.2 gr.), Rem is sensitive to powder load for both powders, and PP more accurate than TG.

Jim - That's way too small a sample to make generalizations about. As you load more, you'll find that overall length, velocity, and charge weight can make as much or more difference as powder or bullet type. If you're taking three out of five rounds in one group as an indicator of accuracy, there's way too much chance of shooter error - believe me, I know about shooter error! - in a sample size that small.

I don't mean to sound like I'm coming down on you about this. You're heading in the right direction as far as load development is concerned. Just do some more testing, checking how variables like overall length affect accuracy and velocity, before you decide on which bullet to stick with.

Chuck, thanks for the thoughtful reply and no offense taken, I realize that I am new and just trying to learn. I am shooting freehand and still have some flyers (due to poor trigger control) that I tried to eliminate by taking the best 3 of 5. In this way, I hoped to see more of an indication of the inherent accuracy of the rounds. Admittedly, it is a very small sample. Others provided some good feedback on their experiences with bullet selection and PP at higher load rates that I can use.

Now that I know these loads feed and function properly in the USP, I can load up some larger batches for more accuracy testing. I will probably focus on one bullet and test powder type, powder charge, and OAL. Any guidelines for determining safe minimum OAL for various loads? These were loaded to a nominal 1.150" with the Rem close to that and the MG closer to 1.145".

[jgedmond]

toddrod, on Sep 28 2009, 10:34 PM, said:

From what I have seen, Power Pistol in in the upper ranges of the suggested load data does make some accurate loads. The Montana gold 124g HP is the bullet I use and the one that I get 3/4" groups from.

Thanks for the feedback in this and your previous posts in the thread. Like you, I have some time to experiment and want to learn learn form my loading. I am leaning towards MG because of all the good comments in this forum and my experience with their availability, price, delivery, etc. Will have to try the HP at some point soon.

[revchuck]

Quote

Any guidelines for determining safe minimum OAL for various loads? These were loaded to a nominal 1.150" with the Rem close to that and the MG closer to 1.145".

Jim - The usual practice is to load as long as possible while still maintaining 100% function. Max overall length for 9x19 is 1.169". This usually works with round nose FMJ bullets, but you'll often have to use shorter overall lengths with hollowpoints or flat nose bullets. Often the manufacturers will have info on overall length for their bullets - you'll usually see it when you check out a bullet manufacturer's loading manual, like those from Speer and Hornady. You also have to take into account the specific gun's magazines and barrel throat...if the loaded rounds don't fit in the magazine, or the bullet gets stuck in the barrel's throat, you have to load shorter. When you load shorter, you usually have to reduce the powder charge slightly. If you've got a chronograph, just load the powder charge to the same velocity that the over-long round gave you (if that's the velocity you want).

CAUTION: On this forum, you'll see 9x19 load data that is longer than 1.169". That's because there are a bunch of shooters out there using 1911s chambered in 9x19; 1911s can take longer OALs since the platform was designed for the 1.27" OAL of the .45 ACP. DON'T use that data with a shorter OAL, since that would probably result in an overpressure round.

[jgedmond]

revchuck, on Sep 29 2009, 09:33 PM, said:

Quote

Any guidelines for determining safe minimum OAL for various loads? These were loaded to a nominal 1.150" with the Rem close to that and the MG closer to 1.145".

Jim - The usual practice is to load as long as possible while still maintaining 100% function. Max overall length for 9x19 is 1.169". This usually works with round nose FMJ bullets, but you'll often have to use shorter overall lengths with hollowpoints or flat nose bullets. Often the manufacturers will have info on overall length for their bullets - you'll usually see it when you check out a bullet manufacturer's loading manual, like those from Speer and Hornady. You also have to take into account the specific gun's magazines and barrel throat...if the loaded rounds don't fit in the magazine, or the bullet gets stuck in the barrel's throat, you have to load shorter. When you load shorter, you usually have to reduce the powder charge slightly. If you've got a chronograph, just load the powder charge to the same velocity that the over-long round gave you (if that's the velocity you want).

CAUTION: On this forum, you'll see 9x19 load data that is longer than 1.169". That's because there are a bunch of shooters out there using 1911s chambered in 9x19; 1911s can take longer OALs since the platform was designed for the 1.27" OAL of the .45 ACP. DON'T use that data with a shorter OAL, since that would probably result in an overpressure round.

Thanks again Chuck. I collected data from this forum on MG 124 gr. CMJ/FMJ loads and saw that most were in the 1.13" to 1.15" range which agreed with Hornady's recommended 1.15" for their 124 gr. RN-FMJ loads.