What’s the trick to accurate auto pistol ammo?

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Unless the bullet is completely the wrong size for the bore you shouldn't be getting 10' groups at 7 yards. I have an old Colt 1903 .32 ACP with a sewer pipe bore that will drop a .309 bullet half way through the barrel before it hits the rifling. It shoots better than that.
 
lordpaxman said:
I’m slightly confused… weren’t both strings with factory ammo? I carry the P365 as well, it’s not a bullseye shooter but it’s surprisingly accurate and precise. At 7 yards it doesn’t take much movement to disturb precision. Even bench resting the gun will yield some amount of deviation.
I don’t see much difference between SD factory and my match ammo through it when comparing accuracy and precision. My process maybe satisfies a fraction of @LiveLife’s GP ammo :). Some loads are going to shoot better than others, and there’s no way to tell other than holes on target.

Can you elaborate a bit? How do you measure head space accurately? I load mostly range brass and case length varies quite a bit but it’s not one of the metrics or QC steps in my process.
Click to expand...

Well, okay. Minutia here we come.

First, there are go-no-go gages for the .45 ACP. You'll then find that not all .45 ACP chambers are created equal or even in the same language let alone measuring system.


It's best to remove the extractor for this but with some uncommon sense and care to detail it can be accomplished with the extractor in place, sometimes, depending on fit and tolerance.

If the extractor holds the case tight, tight, to the bolt face, stop and remove the extractor.
If the extractor holds the case lightly to the bolt face, continue.
Insert a go gage into the chamber and weapon "should" go easily and completely into battery.
Insert a no-go gage into the chamber and the weapon "should" not return to battery.
Trim a fired case to SAAMI minimum OAL. Trim a case to SAMMI maximum OAL Find a .308/762x51 or 6.5x55 case and cut to approximately .920" and expand to chamber diameter.
VELOCITY AND PRESSURE DATA (saami.org)
I'll save you some trouble OAL "should" be .898" -.010". I try to establish .9", when possible, just to keep things simple but the typical user just doesn't have those options so continue.
I keep the expanded .920" plus cases on hand for craziness. I have found a few crazy deep chambers over the years, a few approaching .935" !!

Place an .898" case in the chamber and place a piece of plastigauge (Plastigauge, Plastic Precision Clearance Gauges (plastigaugeusa.com) between the boltface and the cartridge.
Now adjust the length of the overlength cut down brass until you find nil.
Ideally you are looking for a repeatable clearance between the boltface and the cartridge of approximately .0015" to .002".

You may be able to cheat and just stick the plastigauge in there and get a repeatable indication.
Like as not this won't happen, and you'll have to trim down the gauge brass as above and test.

Finally, set aside this sorted brass after trimming to near max OACL and load with measured powder and bullet weights and consistent seating depths. Note: you may have to adjust seating depths to approach any consistency. Sorry I can't recommend anything better than "some" jump into the lands as no two chambers are the same.

I strongly recommend you take a deep dive into barrel to hood fit as the type and kind of inaccuracies described here exhibit similar symptoms.
 
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.38 Special said:
The issue is that the first statement almost cannot be true. At seven yards, no gun is that inaccurate unless there is something horribly wrong with it. If the difference between the two groups - both carefully shot slowfire from a rest - had been an inch or so, then it would be time for accuracy tricks with handloading (most of which have less to do with uniforming your primer pockets and more to do with finding a bullet the gun likes) but at the moment we don't really know anything other than that your groups open up when you go faster.
Click to expand...

I wonder if there was a lot more flinching in the second group, than the first!

With a 45 ACP, the first two to three rounds will be good, after that, FLINCH! With an Ultradot on top, I can see the dot take off, left, right, or in a circle. And all of those movements are proof positive I am flinching. Either pushing the pistol to the left, or to the right, and a combination of both, but pushing the pistol down.

And the more rounds go down range, the harder it is for me to control my flinch.
 
What’s the trick to accurate auto pistol ammo?

Consistency is the key. Not a trick.

@LiveLife put it very well in his post. @jmorris also had good advice. Others did as well.

I would start with a very consistent bullet. A cheap .10 cent bullet is going to be all over the place. Bearing surface, ogive shape/length, bullet weight, all will vary from bullet to bullet. Buy a GOOD bullet. FMJ's are not that bullet. JHP's usually are. Lead bullets CAN be in some guns.

OAL needs to be consistent, as doe's powder charge. Lot's of other things can make a difference too. It really depends on how far down the rabbit hole you want to go.

Shooter input is probably the biggest factor. Trigger time really helps with accuracy more than a $2 bullet will.

And for 7 yards with a defensive pistol, your targets don't look bad at all. Yes, the first one looks better, but be honest and ask yourself how much you expect out of your gun.

chris
 
here is my example of slow shooting and faster shooting with the same load in my cz97b. you can just watch 10 seconds to 2:10. even the flyer with slow shooting i know is me and not the bullet. the shooting was done in same sequence in the videos( i already had the targets up) one after another. i definitely suck when shooting faster which is why i should practice more. if the gun was in a ransom rest i would expect a single hole at 10 yrds.

 
ballman6711 said:
What’s the trick to accurate auto pistol ammo?

Consistency is the key. Not a trick.

@LiveLife put it very well in his post. @jmorris also had good advice. Others did as well.

I would start with a very consistent bullet. A cheap .10 cent bullet is going to be all over the place. Bearing surface, ogive shape/length, bullet weight, all will vary from bullet to bullet. Buy a GOOD bullet. FMJ's are not that bullet. JHP's usually are. Lead bullets CAN be in some guns.

OAL needs to be consistent, as doe's powder charge. Lot's of other things can make a difference too. It really depends on how far down the rabbit hole you want to go.

Shooter input is probably the biggest factor. Trigger time really helps with accuracy more than a $2 bullet will.

And for 7 yards with a defensive pistol, your targets don't look bad at all. Yes, the first one looks better, but be honest and ask yourself how much you expect out of your gun.

chris
Click to expand...
I have also found that aiming helps. But that's just me - and, to be honest, it doesn't help THAT much.
 
Lots of testing.
Load up different loads, shoot them, compare.
Having a low standard deviation helps too.
By now you probably know what bullet weight the gun likes. Stick with that bullet weight, pick a bullet thats affordable to shoot. Take what ever powder you have, load up a bunch of different powder charges. Test them out.
 
Smaug said:
The point was that the high-dollar defensive ammo shot a LOT more accurately than the "blasting ammo".

Based on that, I asked for tips in making accurate ammo for auto pistols, but got a lot of "the problem is you." :confused:
Click to expand...
Based on this, I'm going to close this thread and let the OP try asking the question again in a more distinct manner. It was very confusing as presented and certainly didn't convey his intent

I have to admit that when I first read the OP it did not read like a reloading question...the only hint was that it was in the Reloading subforum.
 
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