Can I do better?

MHouser

MHouser

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Despite my best effort I am getting an avg of 40ish fps spread on my reloads.

Some high level info...

I am using fireformed brass (tried different brands but nothing highend). Uniform flash holes and primer pockets. Necked turned a few batches. Cci br2 primers, varget. Neck sized w/ lee collet die, trimmed, etc. Bullet runout avg approx 3 thou.

Despite my efforts I am not able to get better than a 30-40 Fps spread. I here stories of 5 fps and I'm wondering if I am doing some wrong or need an equipment upgrade or if 5 fps is not realistic.

I am still using the lee safety scale and was thinking that may be the issue, but I am quite careful with it and use check weights, etc and I'm not convinced that is the issue.
 
MHouser said:
Despite my best effort I am getting an avg of 40ish fps spread on my reloads.

Some high level info...

I am using fireformed brass (tried different brands but nothing highend). Uniform flash holes and primer pockets. Necked turned a few batches. Cci br2 primers, varget. Neck sized w/ lee collet die, trimmed, etc. Bullet runout avg approx 3 thou.

Despite my efforts I am not able to get better than a 30-40 Fps spread. I here stories of 5 fps and I'm wondering if I am doing some wrong or need an equipment upgrade or if 5 fps is not realistic.

I am still using the lee safety scale and was thinking that may be the issue, but I am quite careful with it and use check weights, etc and I'm not convinced that is the issue.
Click to expand...

2 suggestions.

1 - All brass is not made to the exact same dimensions, so not only can you use the same head stamps, but you can also weigh each piece and group the same weights together.

2 - Throw that safety scale in the trash and get a decent digital scale. Way more precise and much faster.
 
I wouldn't loose any sleep over it. 30-40 FPS spread is pretty good. Ammunition like Hornady Superperformance has close to an 80fps spread, and cheap stuff like MFS has over 200! The most consistent factory ammo I've tested is Federal Premium, and it was around 30fps. Also, I'd calculate the standard deviation, and be more concerned with that rather than the max spread. If you have one or two cartridges that, say, had .5gr less/more powder, it would significantly impact the max spread, but the standard deviation for 10 shots would be relatively unaffected. I'd also be more concerned with over all accuracy. If you're grouping sub-MOA at 200yds with your loads, I'd leave them as is.

Remington Premier 55gr Accutip

2964
2961
2941
2935
2919
2938
2895
2943
2969
2930

Low 2895
High 2969
Mean Average 2940
Standard Deviation 21.1
Max Spread 74

Above you see that there is one cartridge that was almost 25fps slower than the next slowest. This pushed the spread from 50 fps to 74 fps; however, the standard deviation is still relatively low.
 
You didn't say what calibre or what loadings you were using.
40 fps spread is a bit high.
I'll take a broad guess and say you were loading too light.
Cartridges work best at their rated top pressures (velocities). Bench rest shooters found this out many years ago. Thus, even for 100 yard shooting, bench rest shooters shoot them at full steam, likely higher pressure than will be shown for the same cartridge in any modern loading book.
Cartridges loaded for match shooting, whether civilian or military, will usally be loaded to higher pressure, than will the same cartridge loaded for sporting use.
So, short answer, load them light, expect them to be a bit irratic.
 
I'm using 43.6 gr of varget in my 308 which is middle of the road in terms of max/min charge. Only because I was getting the best accuracy with that charge. I will try the brass sorting thing.

Will likely upgrade scale but reluctant to go electronic because of all the stories of how temperamental they can be. Was thinking of getting a half decent beam scale and having it tuned professionally.
 
Will likely upgrade scale but reluctant to go electronic because of all the stories of how temperamental they can be.
Click to expand...

I haven't found that to be the case with the better quality scales.

Was thinking of getting a half decent beam scale and having it tuned professionally.
Click to expand...

Tuned? Check the calibration with check weights, if it is on, you are good to go.
 
MHouser said:
I'm using 43.6 gr of varget in my 308 which is middle of the road in terms of max/min charge. Only because I was getting the best accuracy with that charge.
Click to expand...

What bullet weight are you using with that load? Many of the long range guys shoot 175gr SMK's with heavier loads than that and report fantastic accuracy, which is the ultimate test of how consistent your ammo is.


Mark
 
Just a follow up of how inconsistentsy goes along with low pressure.
I once had a box of factory loads, IVI Imperial, 100 grain in 243. On the box they said the velocity was 3100 fps, but they seemed pretty mild, so I chronographed five of them with the Oehler 33.
Here are the results.
2522
2473
2547
2564
2602

That's an average of 2540, instead of 3100 and the top to bottom spread is 125!
Some 100 grain bullet handloads shot in the same Ruger 77, with a velocity average of 2955, had a top to bottom spread of just 13.
This is right from my notebok of records.
 
mmattockx said:
What bullet weight are you using with that load? Many of the long range guys shoot 175gr SMK's with heavier loads than that and report fantastic accuracy, which is the ultimate test of how consistent your ammo is.


Mark
Click to expand...

168gr - SMKs or Hornady Match

May go back to the 175 SMKs and try that.
 
I have found that when working up a load, I get decent accuracy somewhere around the middle of the charge range. I can stop there and still have good hunting performance, but, I ALWAYS find that my rounds group tighter and are more consistent if I am shooting near the max listed ranges of the cartridge. So, while I don't chase max velocities, I tend to find that there is better accuracy at a slightly higher powder charges. Case in point, .30-06 rounds I loaded some years ago. I was tired and in a rush so I got some decent groups at 43.5gn of WC735 and called it quits, went home and made up the rounds. Went back to the range to sight in and chrony only to find them to be slightly anemic and less precise than I was expecting. Checked my notes. My .308 165gn rounds were 42.5 gns!! And they were more accurate. Wound up tearing them all apart and starting over. Found a great load at 47gns that did what it was supposed to. Chrony strings were closer and accuracy was sub-MOA. Better hunting round that I could have confidence in.
 
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