Reloading help? Velocities

[CBH Australia]

I was loaned a Chrongraph so today it was a nice day went to test a few rifles and loads.
I have loaded thousands of rounds on a single stage press and have good success in the field.
I am now starting to shoot some club events with sporting rifles.
I don't use match grade components but my rifles are decent and I know the chrony works ok.

My problem is several tests of several rifles were getting an extreme spread of up to 100fps and I expect it should be a lot less.

I understand there are many factors but which would you change first to improve the ES in velocities???

I identified one lot of ammo were jammed to the lands and that can increase pressure s. This came about by trying another projectile while loading without measuring to the Ogive.

I have loaded some .308 in new Lapua cases to shoot in a club match. But still using a 168gn Z-Max and hope to burn these off first. I'm not competitive but I'm gonna burn up what components I have in trial and error and improving my target technique.

One lot of ammo were loaded using a Lee Collett neck die and a Forster seater. A test run for reloading for club events.

Most of my die sets are Redding or Hornady.

Working with what I have , What would you change first in the load technique or proccess???

I have indivually measured powder on some of these loadings so I believe the charge is consistent at least.

I'm sure I can improve something in the process before purchasing different tools and components

 

[Royal27]

I have indivually measured powder on some of these loadings so I believe the charge is consistent at least.

Individually measure every charge. Make them all exact.

You can also check case capacity in all of your brass (or just weight ).

There is no limit to how far down the rabbit hole you can go.

 

[CBH Australia]

Individually measure every charge. Make them all exact.

You can also check case capacity in all of your brass (or just weight ).

There is no limit to how far down the rabbit hole you can go.

Thanks,
I meant I have indivually measured every charge on given batches. That is slow using a balance scale.

Yes , I know it's a rabbit hole just hoping there is a single thing that I should try first.

I guess I thought an ES of no more than 50 would be acceptable .

If I were just throwing charges from a thrower I figured ES should still be below 100

Any idea what to expect if it was factory ammo.?

It's a learning curve and an exercise. It never mattered until I chronographed some loads.

 

[fourfive8]

You're right, you should not be getting 100fps spreads (ES) from otherwise normal loads if they are yielding reasonable groups. First thing comes to mind is possible issue with borrowed chronograph. Need to make sure, somehow, it is working the way it should. Related to that, is it set up correctly? I discovered for shadow slit types, like the Chrony brand, I need to shade the slits from direct sun contact... taping index cards to the diffuser supports is one way. Also make sure bullet path is consistent at about 2-4" centered over both front and rear slits. And make sure unit is far enough away from muzzle so that debris and blast effect on the unit is minimal...15ft at least.

If your group sizes reflect variability that can be explained by the velocity ES results, the chronograph results are likely OK, then it may be loading technique or component issues. Since you mentioned jam length of loaded cartridges, that "flags" a possibility. If you are very close to jam length in OAL, could be that some rounds are touching lands while others are not even though loaded with identical specs with same die settings- just the nature of the geometry of how the ogive of the bullets interact with the leade/throat contact taper in the chamber. Might try seating deeper with a slightly longer jump to lands... maybe .020-.030" jump. One more thing that can be a "hidden bugger"- trim length. Make sure to trim brass consistently to recommended length, usually .005-.010" shorter than SAAMI chamber length. Similar issue as bullet jam length, would be inconsistent contact of case mouth rim with end of chamber. That can really cause pressure variables, thus velocity variables. Not likely cause but worth double checking the trim length.

Least likely but also worth double checking... components and load technique. Make sure primers haven't been exposed to contamination and are seated correctly, bottoming out with a tiny skosh of compression on bottom of primer pocket.

 

[WC86]

For fast fixes +1 to both individual charge measurement (critical to any significant precision for longer range shootin) and maybe chrono issues.

For more unpacking of the topic, at an extreme spread of 100 FPS my sleep addled brain says you should be around an SD of 33 (3 SDs gives you about 99 % of your shots). That does seem high for handloads but several things influence the value of this ES to our discussion and whether we can interpret an sd from it. The two that come to mind fastest are how many rounds was this and was it evenly distributed or did it include any obvious outliers (ex: shot string of 2800, 2795, 2792, 2800, 2700 vs 2800, 2770, 2750,2730, 2700–the first is pretty good with one off round and the second needs a lot of work). As said earlier, a small sample size of only 3-5 shots would invalidate these data as well.

I would expect quality handloads to provide a standard deviation of 10-15fps which typically yields an ES of approx 30-45 (although the evenness of velocity distribution and presence of outliers can highly affect this).

so I say all that to say we really don’t have enough data to help too much. But that said, I’ll say the following about hand loading in general that will likely provide quick improvement:

if metering powder charges with throws instead of measurement of individual powder charges, expect variation of 0.5 grain to 2 grains per throw depending on your equipment. To test this simply, through a few and measure them on your balance. I bet you’ll be surprised by how much variation you get. Compare those powder amounts to your reloading manual to get a rough estimate of how much FPS variability you should be seeing.
That’s the fastest way to cut sd’s and Es’s, all other things being equal. Especially in a cartridge with as small of a charge as 308. Matters less the more powder you are putting into the case but in a 308 a grain can mean 50fps or more.

as far as chrono, if it is optical It’s challenging to trust. Move to Doppler chrono if you want to get serious about dialing loads. If it is Doppler and the buddy you borrowed it from gets good numbers from it, it’s probably an ammo issue.

either way, it is a rabbit hole that is very deep. But definitely take the red pill if thinking about how far you want to go! It can be fun and rewarding

 

[WC86]

Oh, and as far as handloads vs factory ammo and precision driven by reloading practices I offer the following from precision rifle blog (I dabbled in the precision shooting community—not for hunting but for competition):

How Much Does SD Matter?

As long-range shooters, we tend to obsess over every little detail. After all, we’re trying to hit r...

precisionrifleblog.com

the above is the link to that article. His site is a wealth of information about achieving precision through reloading. He has a newer article series about consistency in ammo that is very good too

 

[BourbonTrail]

I’ll throw one more tunnel in the rabbit hole: neck tension.
This echos @fourfive8, If you have consistent powder charges, but your necks aren’t consistent you’ll see a velocity spread. After checking everything else mentioned, may need to anneal/trim/deburr etc.
Same goes for primer pocket deburr. It can cause powder ignition changes.

 

[WAB]

Oh, and as far as handloads vs factory ammo and precision driven by reloading practices I offer the following from precision rifle blog (I dabbled in the precision shooting community—not for hunting but for competition):

View attachment 406743

How Much Does SD Matter?

As long-range shooters, we tend to obsess over every little detail. After all, we’re trying to hit r...

precisionrifleblog.com

the above is the link to that article. His site is a wealth of information about achieving precision through reloading. He has a newer article series about consistency in ammo that is very good too

I know the fellow whose blog this is. He cleaned a range to 2400 in TX a couple of years back. He knows his stuff and backs it up on the range.

 

[crs]

The biggest improvements for me were the use of the Lyman Digital Powder system 1200 DPS and the 24 inch drop tube plus the use of fine grain or ball powder. The 400 grain Woodleigh ammo for my .405 WCF has a SD of 0.0 (zero) fps for 5 shot test groups with VV N133. This charge was set off with Federal match magnum large rifle primers which boosted MV by 37 fps over other common magnum primers .
Best ever for me.

There were three witnesses to the final load shooting and the the chrono display and only one is related to me!

After a lot of practice shooting at the range, I took my Miroku/Winchester 1895 .405 and this ammo to Africa for Cape buff and all components did the job well. It was sometimes slow loading the ammo, but well worth it for the confidence and performance ; every shot went EXACTLY where it was supposed to.

 

[Pheroze]

Might try seating deeper with a slightly longer jump to lands... maybe .020-.030" jump.

If the chrono is accurate I would start there personally. Maybe back them back a little from the lands?

I switched to a magnetospeed because I found those optical ones to be very troubling to work with. Much more accurate. I think a quality chronograph is essential.

Good luck, this is a weird one.

 

[shootist~]

All the above answers mention Consistency in one way or another.
How you get there can vary, but that's the name of the game if you want to see low SDs.

Powder drops to +/- 0.1 grains is good, +/- 0.05 grains is better.

Quality of brass, including neck tension. (An obvious "Duh", is don't mix your brass.) I start annealing after the second reload.

Uniforming primer pockets. Not required on Lapua, but I will still use the uniforming tool to clean the primer pockets after each firing.

Components: Find out what components (primers and powders especially) the top shooters in your area use.

 

[Troubleshooter]

I switched to a magnetospeed because I found those optical ones to be very troubling to work with. Much more accurate. I think a quality chronograph is essential.

I switched to the LabRadar for the same reason. Wind and sun angle adversely affected the optical chronograph that I used for many years. The Magnetospeed wouldn't be feasible for some of the guns I was testing. Expensive, but "buy once, cry once" as they say.

 

[gbflyer]

Then sometimes you’ll get loads that produce single digit SD and don’t group worth a hoot. Switch powder, SD goes through the roof and they go in the same hole.

It’ll make an otherwise sane person look for a prescription.

 

[shootist~]

I switched to the LabRadar for the same reason. Wind and sun angle adversely affected the optical chronograph that I used for many years. The Magnetospeed wouldn't be feasible for some of the guns I was testing. Expensive, but "buy once, cry once" as they say.

+1.
Also, the Magnetospeed is very accurate, but does affect your group in my experience.

With the shortage of components, it's best (IMO) to just pay up and get the LabRadar.

I have both, btw. The MV3 has been sitting in the garage since last Christmas. The labRadar is more complicated, however. Read the instructions at least couple of times before set-up. And keep them with the unit. Mine links to my Android phone, which is easier (for me) than operating it from the on board menu.

 

[wswolf]

Try switching primers. In my experience magnum primers are more consistent with spherical powders than standard primers, even in small cases. Many modern powders burn most consistently at around 60,000 psi. Working up toward the maximum published load could be beneficial.

 

[CBH Australia]

It's a Chrony Chrongraph with the plastic shields supported by the wire rods.

The ES is high as I thought. Discounting the Outliers it might be less

I saw its owner get low SD with his rifle and loads dedicated Long range set up in 6XR.
I expect he is using a good powder dispenser although most of loads were grouped as individually measured loads.

I am using extruded powders. Australian ADI powders

I am using Tikka rifles, limiting OAL due to magazine length. But I have identified one brand of projectiles were a jam fit. Changing this. This is where the micrometre dies would be useful as I could adjust, record and repeat settings easily if using different Projectile types.

I'm thinking the projectile s could be seated marginally deeper and any variation measured to avoid a jam fit on the range.

Looking at my crude notes I can see one record of 4 shots through my .280ai with the jam fit getting only 34fps in a small sample and these jam fit getting theax overall velocities . With primer flattening starting to show. I'm not running hot loads.

I did not have a methodical approach in regard to sample quantity for data comparison. I expect shooting 10 rounds for velocity comparison might be required

I'm going to do a couple of small samples today and hopefully test these today.

I was hoping there was one thing or a series of steps that you might suggest I work through on order to eliminate the most common cause of these velocity inconsistencies.

I have researched both the Magnetspeed units and the Labradar units

It falls out something like this in Aussie dollars with about 3 choices
$350, Caldwell Chrony
$500-$600 magneto sporter.
$750 magneto v3
& $1050 dollars for the Labradar and then they offer a trip and carry case as extras.

At the moment I don't shoot long range or really need to verify velocity but I have use of this unit and I am trying to develop repeatable loads for a few rifles and shoot a little more.

And it's a learning curve and experience before I put any more dollars down .

 

[Ridgewalker]

If the chronograph is questionable, see if there’s a club chrono or someone in your club who would let you shoot over his just to verify. Clouds and atmospheric conditions can alter chronos with sky screens IME.
Just a thought…There are some good Youtube videos on Saterlee’s ladder method which I have used successfully. A number of top dogs here in the USA use his method.

 

[meigsbucks]

I have all three chronographs and did a velocity comparison and posted it on this site.
Thread 'Chronograph Comparison'
https://www.africahunting.com/threads/chronograph-comparison.51455/
Maybe this will help you.

 

[JimP]

You can also shoot some factory rounds over it and see what that spread is.

Or even take some low cost rounds like 22 Lr and see what they do

The one time that I had problems with my Pac it turned out being I had the cords laying on each other. A call to tech support and all was well. This won't be your case but it could be something just as simple.

 

[Shootist43]

I spend a lot of time and effort uniforming the brass. Use only one brand of brass for any given test. Don't mix new and fired brass, uniform the primer pockets and flash holes, clean the primer pockets prior to reloading, all brass should be trimmed to the same length and fired the same number of times, annealing will be required after a number of rounds have been fired. All powder charges are measured on a balance beam scale. All shots fired should be from a cold barrel.

The pay-off comes as follows: My 404 Jeffery produced velocities of 2300, FPS, 2309 FPS followed by 2306 FPS. All shots were touching at 100 yds. Von Gruff gave me the load and told me to expect 2300 FPS. Are you using a load similar to what other guys are using?

Be advised there are no shortcuts.