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Joined: Sep 2020
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I've been trying to get the most accurate loads practical but I have not been able to reduce variation in velocity (ES and SD on the chronograph). I realize that this variation is not necessarily and maybe not even likely the cause of a loss of accuracy, but I figure there are three categories things that contribute to accuracy:

combustion
the gun
bullet aerodynamics

I'll work backward to get to SD in velocity. The bullets need to have consistent aerodynamics, or BC. I don't trim meplats or point bullets for handguns, but I have tried different bullet makes and sorted bullets by weight looking for consistency. Bullet mass affects combustion but it could also indicate differences in length. In any event, I don't think BC consistency has to be that great to have accuracy at 50 yards, or even 100 yards.

The gun has to be consistent whether it's consistency in barrel lockup and barrel to sight or chamber to forcing cone alignment. There are also things like barrel harmonics, bullet stabilization and so on. Pistolsmiths have a lot of ways to accurize a handgun. I shoot a revolver and it shoots consistently less than 1" at 25 yards. But the group is almost always tighter horizontally than it is vertically. A good group will be 0.9" tall but only 0.3 to 0.4" wide. With a revolver, the barrel-to-cylinder gap and the alignment to the forcing cone of each chamber has to be consistent. I can check the consistency by measuring directly and by grouping one chamber at a time and so on. I think there is more potential in the gun but I suspect the ammo is not delivering yet.

Consistency in combustion comes from the consistency of the primer, the brass volume, the neck tension, maybe the concentricity of the bullet seating, seat depth, the powder charge mass, powder position, crimp, starting friction, and so on. As I mentioned, I'm not getting consistent velocity. My better SD's are typically around 20 fps. I've had some 5-shot SD's as low as 4 fps, but they fall apart with more shots. Now obviously, 40 fps spreads are not going to meaningfully affect bullet drop at 50 yards, but it could be affecting the point of impact with variations in muzzle rise.

I've done tests of three different primers, and I've tried sorting primers by mass. I'm using brand-new Starline brass and have tried sorting it by weight (didn't try sorting by water mass). I've tried factory sizing (as the new brass comes) and also sizing it with my carbide die. I've tried 12 different powders (about half of which aren't very promising for accuracy but I had them). They include Alliant, Hodgdon, and VV. The best results so far have been from HP-38 but it's also the fastest powder I've tried. I have mostly slow and medium powders. I just ordered some Titegroup which I'm hoping might deal with primer inconsistency and powder position variations. Of course, I trickle the powder. I mentioned that I've tried different bullets. I don't have any Nosler, Sierra or Zero.
The best I have is XTP and some Remington JHP. I sort them by mass primarily to get consistent pressure curves. I've done tests with various levels of crimp using a Lee FCD and a Redding micro-adjustable profile crimp die.

The bottom line is I've tried a lot of things that don't seem to matter much. I still get inconsistent velocities and I think there's another factor that's blocking progress. I want to see lower SD's for velocity and then see if the POI stops the vertical stringing.

GB1

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Heavy bullets, small charges of fast powder.
If you're shooting Bullseye go to bullseye l forum and read.
I leave the chronograph at home.
Get something decent and load a lot and shoot a lot.

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What is the accuracy and precision of the chronograph you are using? I have a "Shooting Chrony" and I've seen velocities vary with various weather conditions. Powder temp. can cause velocity variations too. Hotter chamber, hotter velocity. Some powders are clearly more sensitive than others. Looking at adding the Radar chronograph that came out a few years ago. Wish the $600 price would come down... While ES/SD matters, what matters more (to me) is accuracy down range.

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The first place I look for accuracy problems with a handgun is in the mirror.

There’re tough to shoot, though optics help. Not sure if anything other than choice of primer/powder/bullet, and neck tension/crimp is going to make meaningful difference. Not even certain that velocity spreads, unless really wide, matter all that much. All sounds like good clean fun though

How about some details on your setup?


What fresh Hell is this?
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[quote=Pappy348]The first place I look for accuracy problems is in the mirror.

Amen!

Develop your skills, make sure your pistol is up to par, then you can concentrate on your ammo. I shoot a Smith 52 so I know the pistol is accurate. After a year of practice, I began to see differences in my ammo. Bullet selection was the biggest difference, followed by brass sorting. Same head stamp loads reduced group sizes by eliminating unexplained flyers. I have not tweaked with powder charges since the pistol has a narrow range of acceptable loads but 231 does perform a little better than Bullseye.
I am pleased with my work on the 52/38 Special so am now concentrating on 9mm. First lesson I learned is to buy good jacketed bullets. Even the best plated bullets are far behind jacketed in performance. There are many more variables on the 9mm so I am still working.

IC B2

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When I was shooting and loading more than I've been in the past few years, every time I got a new batch of handgun brass I'd go through and trim all the cases to a uniform length and just take off the burr, no chamfer to speak of. For revolvers, so my crimp would be consistently located half-way up the cannelure and of consistent "pull." For autopistols so I would get a consistent amount of taper crimp and so the headspace relationship between my loads and the chamber were consistent. Maybe it helped, maybe not, but it's what I did.


Mathew 22: 37-39



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Originally Posted by Pappy348
The first place I look for accuracy problems with a handgun is in the mirror.

There’re tough to shoot, though optics help. Not sure if anything other than choice of primer/powder/bullet, and neck tension/crimp is going to make meaningful difference. Not even certain that velocity spreads, unless really wide, matter all that much. All sounds like good clean fun though

How about some details on your setup?

Gonna guess if he is this serious about loads and testing ammo and theories its a waste to ask if he can shoot well enough.....


We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
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Whenever I bought a new competition pistol, I loaded a variety of loads with increasing powder charges and headed to the range with my Ransom Rest. I let the groups tell me which load I was going to use. I have shot hundreds of thousands in practice and competition and reloaded nearly all of them and have yet to do anything to the brass other than clean it.
Phil

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The best thing you can do is get a dry firing device, like one of those laser trainers.


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Wow!...a zombie thread.

I was almost thinking this was someone having some fun...so I checked how close we were to April 1...then I saw the date of his post. 4 months old and no follow up. If he's seriously looking at those things...he either has or really neads a Ransom Rest. I vote for checking the shooter as well.

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I have a Ransom rest, windage base and several inserts.
Damn thing is mandatory once your eyes go to hell.


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