What’s the trick to accurate auto pistol ammo?

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Smaug

Smaug

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I was at the range the other day shooting my Sig P365 carry gun.

First, I shot a group with y carry ammo. Some old Winchester that I can’t remember what it is. That’s the top target. Seven yards, but still impressive, to me.

Then below, I shot a couple mags’ worth of PMC FMJ range ammo. I shout it just slightly faster, but not faster enough to explain how big the group is!

What’s the trick to accurate handloads for autos?

0F2A11BB-32E7-48E9-9A14-86CEB79CF868.jpeg
 
Smaug said:
What’s the trick to accurate handloads for autos?
Click to expand...
Reduce/eliminate as many reloading variables as you can - https://www.thehighroad.org/index.p...-and-discussions.778197/page-10#post-11419509

General purpose range blasting/plinking "reloads":
  1. Scale and calipers not checked with check weights/pin gages
  2. Mixed range brass with various headstamp and different resized case lengths
  3. No regards to number of reloadings
  4. Primer selection based on availability/cost
  5. Primer pocket not cleaned and press primed to flush
  6. Powder selection based on availability/cost
  7. Powder selection not specific to metering variance
  8. Bullet selection based on availability/cost
  9. Bullet weight not sorted
  10. No regards to tilting of bullet during seating
  11. Random resized case used to set case mouth flare and taper crimp amount
  12. Taper crimp amount "rough" estimated
  13. Wide range of OAL variance accepted
  14. Longest working OAL that will work in multiple pistols
  15. Wide range of bullet setback accepted or not checked
  16. Finished rounds checked for reliable slide cycling and extraction/ejection of spent cases
  17. Not every finished round checked with case gage/barrel
  18. Finished rounds stored/transported in loose/bulk containers
  19. Finished rounds exposed to sunlight and allowed temperature fluctuations

Match grade "handloads":
  1. Scale, calipers and even micrometer checked with check weights down to .1 gr or less and pin gages to .001"
  2. Sorted brass by headstamp and resized case lengths
  3. Once-fired brass preferred (New brass if you can afford it)
  4. Brass selection based on case wall thickness, finished OAL consistency and no bullet setback
  5. Primer selection based on smallest groups produced on target
  6. Primer pocket inspected/cleaned and hand primed to around .004" below flush to preload anvil tip against priming compound
  7. Powder selection based on smallest groups produced on target
  8. Powder selection specific to metering variance of around .05 to .1 gr preferred
  9. Bullet selection based on weight, ogive and finished OAL consistency (Example: RMR in-house jacketed bullets)
  10. Bullets sorted by weight
  11. Attention to prevent tilting of bullet during seating (May use stepped/"M" style expander)
  12. Shorter resized case used to set case mouth flare and taper crimp
  13. Taper crimp calculated by bullet diameter (.022" added to sizing of bullet)
  14. Tighter OAL variance preferred around .001"-.002"
  15. No bullet setback preferred
  16. Finished rounds checked for smallest groups on target and if not at max charge, OAL incrementally decreased by .005" to fine tune accuracy specific to barrel/pistol
  17. Every round checked with case gage/match barrel
  18. Finished rounds stored/transported in 50/100 round ammo boxes
  19. Finished rounds kept out of sunlight and even in insulated box/ice chest to stabilize powder temperature
 
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LiveLife said:
I agree that slow fire may be better suited for accuracy testing.
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You just about exhaustively covered the "basics". :)

I'll shorten it up a bit. Find your head space and load over all case length to at or near nil.
True the case mouth to a sharp and axially, radially, surface.
Consistent powder weight.
Consistent bullet seating.

You can pick and choose what @LiveLife has provided but that accurate head space on the case mouth is the most important physical dimension. I use an internally and externally sized.308, cut down past the neck, with a few teeth cut into the "mouth" to clear carbon from the front edge of the chamber without removing metal. I'm probably not drawing a good picture with words, so I don't mind questions.

I load for a particular Ser. 70 Gov. .45 and near 80% of accuracy was contained in just 20% of the work. Just accurate head spacing on the case mouth and keeping the forward edge of the chamber clean. Of course, the last 20% is 80% of the work but isn't that how it usually is?
 
Smaug said:
What’s the trick to accurate handloads for autos?
Click to expand...
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.
kopcicle said:
I'll shorten it up a bit. Find your head space and load over all case length to at or near nil.
Click to expand...
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.
 
I've no idea how long folks have been shooting, unless I was involved in their training. Having said that, there are hundreds of data points that can be involved in an 'accurate' round, not the least of which is the weapon, the shooter, the shooting environment, and the like. Live Life makes good points for the aspect of accurate handloads, but even if one produces the absolute perfect loads, all the other factors are in play as well.

Factory loads are, factory loads...by default. By far almost all L.E. departments use factory loads (due to warranty issues on weapon platforms and liability issues in court) and they are good enough to produce competition-level shooters. Can you be more accurate with handloads? Yes. Does it still depend on factors other than the round? Yes.
 
It’s a defensive weapon. I understand wanting to be able to hit a target but as long as all your rounds are inside the thorax at 20’, you’re golden. Next work on your speed and point-shooting skills to keep your shots in that area as fast as you can.
It’s a little like asking how big a turbo you need to get your ‘73 Pinto ready for the Grand Prix. :eek:
 
If your buying ammo it's exactly the same game as your rifle. You have to find what your gun shoots and buy a pile of that ammo. If your hand loading it's the same game, except you control more of what's happening. Find a bullet, test a powder or six and tweak oal as needed. I found that my drop in storm lake barrel always produced better groups, so depending on your goals that may be a good option.
 
twarr1 said:
Good responses to the question about hand loads but I’m wondering what does handloads have to do with “some old Winchester” and PMC rounds?
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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:
 
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There can be a huge difference.

Just the other day was testing ammo (factory) in an M92X. 2 5-shot groups at 25 yds per ammo type, free hand.

The best scored a 3.4 in group and a 2.6 inch group. The worst a 7 inch and an 8 inch group. Same gun, same shooter, same hour.

They don't always shoot to the same point of impact, either.
 
Shivahasagun said:
There can be a huge difference.

Just the other day was testing ammo (factory) in an M92X. 2 5-shot groups at 25 yds per ammo type, free hand.

The best scored a 3.4 in group and a 2.6 inch group. The worst a 7 inch and an 8 inch group. Same gun, same shooter, same hour.

They don't always shoot to the same point of impact, either.
Click to expand...
Kinda makes you wonder why "factory ammo" is the bellwether standard against which handloads are judged, doesn't it? :thumbdown:
 
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...
have you shot the "blasting ammo" as slow and deliberate as the more expensive ammo during the same range session?) we all have good and bad days so same range session is better for comparison) at 7 yrds i doubt it would make that much of a difference in grouping, maybe point of impact will be different. i know my groups are bigger the faster i try shooting. if you have 38 spcl and 357 mag. try alternating in a cylinder same 7 yrd range shoot slowly sa vs da whatever you are better with and check the result. i may try that myself next time i go to the range.
 
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...

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.
 
GeoDudeFlorida said:
Smaug said:
The point was that the high-dollar defensive ammo shot a LOT more accurately than the "blasting ammo".
Click to expand...
Kinda makes you wonder why "factory ammo" is the bellwether standard against which handloads are judged, doesn't it? :thumbdown:
Click to expand...
It's been my experience shooting various factory premium JHP and cheaper target ammo along with white box that most pistols are capable of producing around 1"+ groups at 7 yards, 2"+ at 15 yards and 3"+ at 25 yards which have become my accuracy standard for ammunition, factory or reload/handload.

When I shot USPSA matches, I initially used factory ammunition and tested various brands/weights to narrow my accuracy preference down to PMC/S&B among FMJ offerings. When I started reloading, my group size shrank by over 40% compared to more accurate factory ammunition.

BTW/FYI, when I did shot group size comparison between premium JHP to factory white box/minor power factor match rounds, group sizes at 7 yards were comparable with premium JHP shooting about an inch higher to POA, which is not that significant for defensive shooting distances/purposes.

Smaug said:
Sig P365 ... 7 yards slow fire ... rapid fire
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Looking at your target groups, I am seeing obvious left/right along with vertical dispersion likely from trigger finger and support fingers push/pull on trigger/grip that exaggerated from slow fire to rapid fire.

And I think other members are seeing this and recommending focus on grip/trigger control to reduce shooter induced input on target group size difference - https://www.thehighroad.org/index.php?threads/trigger-control.834737/page-2#post-11245640

I understand Sig P365 is a subcompact but my Glock 26/27 subcompacts maintained around 1" groups at 7 yards using different ammunition, factory or reloads. Earlier this year, I bought my BIL Taurus G2C, and at 7 yards, produced around 1" groups with factory and my reloads brand new out of the box (It surprisingly had nice smooth trigger that did not jerk/move the front sight when dry fired :thumbup:) which was similar in experience to coworker's G2C he bought for his wife.
 
jmorris said:
It’s not really a trick but a good JHP will help you in your journey, unless it’s you, then a machine rest can remove that part.
Click to expand...
Didn't Nosler at some point advertise their Competition Match JHP as being for target use only? Or maybe I'm confusing them with Hornady's HAP? Anyway, it's been shown a few times a well-made jacketed hollow point has an accuracy advantage over even the much-praised, revered full wadcutter. So, there is that.
 
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