Pistol Good SD numbers

Discussion in 'Reloading Forum (All Calibers)' started by AJC, Sep 21, 2019.

  1. AJC

    AJC

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    What do you expect or consider a good and decent range for standard deviations on a pistol cartridge? I have been watching a bunch of reloading videos and powder reviews, with most loads having sd numbers way over a hundred. I have also watched some factory loads over a crono be about 15-20 fps. Single digits seems to be the goal in ing range rifle, is this even achievable in a pistol cartridge?
     
  2. SSL

    SSL Gold $$ Contributor

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    Only my opinion, but to me SD is much more important (within reason) in rifles than it is in pistols due to the discrepancy in distances involved. High SD numbers can really tell at long distances but mean little to nothing at typical pistol ranges. Years ago I was a heavy competitor in a local pistol club (.45 ACP) and obsessed over loading details. It soon became apparent that when talking about 25 yards, often higher SD loads performed more consistently than those with low numbers. Made no sense to me, but I did start worrying more about group sizes rather than numbers.
     
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  3. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    This is why people load thousands of rounds on a dillon while watching tv rather than on a single stage press weighing charges.
     
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  4. AJC

    AJC

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    I thought the advantage of the dillion was that it produced on average more consistent rounds than hand loads for huge batches. I thought that the mechanism provided consistency that was hard to match in larger batches.
     
  5. Sniper338

    Sniper338

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    Your barking up the wrong tree here. You cant shoot the difference in 5SD or 150SD with a handgun.

    Put the handgun ammo in a rifle and you could see the difference.
     
  6. AJC

    AJC

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    That's where I was going 200 yd 357 mag shots while shooting siloette. Same load processes still apply
     
  7. Forum Boss

    Forum Boss Administrator

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    Generally pistol ES and SD factors, as long as ES is < 50 FPS, is meaningless at the distances most pistols are shot, and given the accuracy most shooters can hold. Now if you are talking a bolt-action silhouette pistol, that's another story.

    But bottom line -- load for accuracy and low recoil if you're shooting paper inside 50 yards. If this is for a discipline with minimum power factor, SD does become relevant as you need to hit the target velocity.

    That said, 90% of pistol shooters can't hold 3" at 20 yards, so fussing over this stuff is pretty pointless.
     
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  8. Sniper338

    Sniper338

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    Work up a load that shoots best, then set a powder dispenser to drop around about that load. I still dont think .4 on either side of the target weight will make a difference in it.

    If it makes you feel better load them individually. How tedious you want to be is up to you. Probably not worth the time though. Only way to find out is test it each way.
     
  9. AJC

    AJC

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    One thing I was looking at was powder in videos. I was intrested in power pistol but the sd numbers I was seeing were like 250. That's a huge swing. I have used unique but not cronographed my loads yet. I'm guessing getting the case length and crimp exact may be the biggest factors but I'm trying to figure that out. I shoot a lot of pistol 357 loads but I feel like in my lever action rifle those same loads would not look near as consistent. I decided this would be the next logical step in my learning ladder. Any good things I learn from the rifle loads sure could not hurt the pistol loads. At this point I still load them the same but I may switch to something like h-110 or 300mp in the rifle.
     
  10. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Not at all. Its for volume not even close to consistent. But 250 is so far off thats comical on a 1000fps load. You can do better than that pinching powder and using assorted primers.
     
  11. AJC

    AJC

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    You could say I was shocked to say the least and I came back into the fold for a reality check. The number I got above is 50 and I can see that as reasonable and when I start testing what I will set as a goal. I love the testing on jonnys reloading bench because of how you can watch how some powders just seem to be better suited to reloading certain cartridges. Your advice is always given full value.
     
  12. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Pistol powder meters like water. Thats how you can get away with a volumetric dispenser like a dillon and stay consistent. My 45acp toolhead hasnt had a wrench on it in 30yrs and still dumps bullseye to the same weight and processes brass the exact way it did back then.
     
  13. ToddKS

    ToddKS Gold $$ Contributor

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    One place where ES can be an issue for pistol shooters is when you are dealing with a required power factor. You don't want a 50+ FPS ES if you are close on power factor. You could get unlucky and fail at the chrono.

    My 9mm match ammo loaded on an autodrive 1050 with N320 has an average ES of 15-20 FPS tops. Most rounds are within 10 FPS ES.
     
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