Projectile weight vs accuracy?

[oremike]

I also dont have anything else to do with my new reloading gear once I develop this hunting load.

Must be time for a new gun then! The correct number of guns after all is just one more.

 

[erslll]

I do understand where you are coming from but I agree with @Longwalkhome. I think you are overthinking/making it more complicated than it needs to be. It sounds like you are getting good results. Can't argue with that but there are a lot of variables involved and I would venture to guess that a 119.9 grain bullet is pretty low on that list of variables.

 

[ron]

Having spent many years reloading for competition accuracy many other factors will have a much larger affect on accuracy than 1/10th grain variance in projectile. Such as Bullets. Match bullets like Sierra Match Kings or Bergers. Brass manufacture and/or lot number will make a huge difference in accuracy. Primer manufacture. Each load may prefer one
brand of primer. Different loads will prefer different primers. Reloading equipment type and brand used affects bullet
concentricity. Last but not least is shooter skill and equipment used. Rifle, scope, mount and bench rest set up. Good
luck have fun.
Stock 308 Savage 5 rounds at 100 yards.

 

[saxon]

considering the ogive might be off as well or the length by 10 K, do you really want to run down all those rabbit trails?
example, 300 blackout 110 grain length varies from 1.050 to 1.080 load developed for the 1.050 and at 50 yards 5 shot group the hole is
.408 load the 1.070 group leaving it log on the COAL so as to be seated at the same depth as the 1.050 and the hole is .435ish

load all lengths so the seating depth is the same in the case (the COAL is different for each length but the depth of the seat in case is the same) and the hole for 5 shots is still .500

 

[saxon]

Having spent many years reloading for competition accuracy many other factors will have a much larger affect on accuracy than 1/10th grain variance in projectile. Such as Bullets. Match bullets like Sierra Match Kings or Bergers. Brass manufacture and/or lot number will make a huge difference in accuracy. Primer manufacture. Each load may prefer one
brand of primer. Different loads will prefer different primers. Reloading equipment type and brand used affects bullet
concentricity. Last but not least is shooter skill and equipment used. Rifle, scope, mount and bench rest set up. Good
luck have fun.
Stock 308 Savage 5 rounds at 100 yards.
View attachment 998521

what he said. i had a 3006 that i had a 168 MK load for that would or could shoot .500 groups at 100 yards

 

[BigGame]

I agree with the general tenor that 0.1gr bullet weight is not an issue with hunting bullets. But regardless, don't throw any away. You've binned them into representative piles and you're using one pile for load development. Once that load is developed, you can shoot the other bins. You might see a tiny change in POI (might), but you will still be adhering to the accuracy-enhancing practice of using a consistent set of components.

If you're really curious what 0.1gr difference in weight might do, plug some scenarios into a ballistics calculator and see how the POI changes with a change in projectile weight. Use an offsetting change in velocity as well, if you feel you can estimate it. Then look at the practical difference at 300, 600, 1000 yards - whatever makes sense with regards to your hunting range. I'm guessing the calculated difference will be itty-bitty at relevant ranges.

I also dont have anything else to do with my new reloading gear once I develop this hunting load. If I can quantify something that improves my precision, I'll do it.

Must be time for a new gun then! The correct number of guns after all is just one more.

There always seems to be something else to do with your reloading gear, if you love to reload. A new gun always works. Trying a different bullet/powder/primer/case in the same gun also works. Just trying different experiments with the same gun/load also works. Some people find a good load, build a bunch of them, and are done. You sound like the type of person (like me) who finds a load, builds a few, finds something else to tweak, builds a few more, and so on. Never build too many, because the moment you do you'll discover something different about your process and you'll feel compelled to strip those loads back down. Ask me how I know. Enjoy!

 

[Koda]

I agree with the general tenor that 0.1gr bullet weight is not an issue with hunting bullets. But regardless, don't throw any away. You've binned them into representative piles and you're using one pile for load development. Once that load is developed, you can shoot the other bins. You might see a tiny change in POI (might), but you will still be adhering to the accuracy-enhancing practice of using a consistent set of components.

If you're really curious what 0.1gr difference in weight might do, plug some scenarios into a ballistics calculator and see how the POI changes with a change in projectile weight. Use an offsetting change in velocity as well, if you feel you can estimate it. Then look at the practical difference at 300, 600, 1000 yards - whatever makes sense with regards to your hunting range. I'm guessing the calculated difference will be itty-bitty at relevant ranges.




There always seems to be something else to do with your reloading gear, if you love to reload. A new gun always works. Trying a different bullet/powder/primer/case in the same gun also works. Just trying different experiments with the same gun/load also works. Some people find a good load, build a bunch of them, and are done. You sound like the type of person (like me) who finds a load, builds a few, finds something else to tweak, builds a few more, and so on. Never build too many, because the moment you do you'll discover something different about your process and you'll feel compelled to strip those loads back down. Ask me how I know. Enjoy!

What I should have asked is what kind of projectile weight tolerance is noticeable. Now for my application my minimum goal is 1MOA... which I think is achievable. If say... +/- 3/10gr projectile weight stays within 1MOA then Im fine with lumping them all together. Not that I would complain if my reloading will get me less than half MOA... It might, I just dont have enough data points yet to know..

I invested in reloading just for this rifle to make a better hunting round. After this Nosler Partition Im going to develope a load using a monolithic projectile for reasons. Eventually I will buy a custom CDS dial for my Leupold scope for each thought with the Nosler Partition I may still just zero 2" high and use my MBPR for that. As far as what to do with my reloading investment... I "might" develope a monolithic load for my lever gun, and im considering reloading .223 for my AR15 just for the fun of playing around with any combinations I can think of. Realistically though, i mostly only care about my 25-06 cause I just love that rifle and caliber.

Im close... I pretty much think I have my recipe for my first ever reload... im just fine tuning the details (like bullet weight..) and need to validate the recipe with about 20 rds at the range soon.

 

[Certaindeaf]

Without a Ransom rest or the like, (and maybe not even then) Even in my younger years, It would be difficult for me to claim accuracy upset over .1 grain difference., Though I hear your quest for perfection, and can relate..
Not being concentric, unbalanced, poor seating or other manufactured or procedural failings would be a different story.

As an aside; I have been using primarily Nosler polycarbonate tipped projectiles on most all my rifles without issue for their game expansion, and accuracy, since they first were made available to the public. (You'd think I'd own stock by now) I have long since stopped measuring and weighing them considering them "good enough" for me....again, for me.
Not to suggest anything disparaging about Speer, Hornady or Barns which I have also had good performance with, but keep going back to Nosler.

There was a benchrester, nearly a hundred years ago now, that went to trials and hand loaded the same brass shell over and over till the match was finished. That seems somewhere between dedication to perfection and insanity.

That was barrel maker Harry M. Pope and it was more like 30,000 shots with one piece of brass using one of his 30-40 Ballard guns. Cast bullets/powder charges by volume.

 

[Knebel]

You know this is quite interesting, I have a box of cast 400grain 500mag projectiles. They range anywhere from 378 to 399.9grains

When I load, I sort the closest ones out together...lets say I have a bunch of 389 ones and some that are 392gain then I'll file the meplat of the 392grain down a little to reach 389.

This makes for more consisten batches of ammo. I dont do that with any jacketed bullets of course... but I have noticed differences in accuracy and recoil If I dont do this.

 

[Lilhigbee]

In my OPINION the weight variation from one bullet to another isn't going to make a noticeable difference. If I wanted to KNOW if it did, once I was sure my loading process was consistent I would load fifty of the target-weight bullets and ten of the lightest and ten of the heaviest, all with the same process. Then I would shoot four five-shot groups of the target-weight loads, two five-shot groups of the lightest loads, then two more five-shot groups of the target-weight loads, then two five-shot groups of the heaviest loads, then four more five-shot groups of the target-weight loads. By mixing the test-weight loads in the midst of the target-weight loads you can check for outlying influences like shooter fatigue, barrel heat, weather, etc. That is a lot of shooting, but it is about the most scientific way to test them practically. You could shoot four-shot or three-shot groups or shoot fewer of the target-weight groups, but I think this regimen would give reliable information on the importance of bullet weight to accuracy.

 

[Koda]

I thought about a weight test but it sounds like it wont be noticable within +/- 1/10th grain. Im thinking I will finish my load development with nominal weight bullets then on the side load 5 @ 3/10gr under, 5 @ 3/10gr over and see what happens. The majority of my supply land within +/- 2/10th grains so I wont need to worry about it if the +/- 3/10th test is fine and I will know what my tolerance range is.

 

[tac]

1/10th grain = 1/70000th of a pound, or 1/4375th of an ounce.

This is how my 35-year-old Krico 650S shoots with my handloads - three shots here @100m.


BTW, I actually enjoy my shooting, too, but I'm not crazily into the reloading thing. You DO realise that just picking up that bullet has likely added at least 3/1000th of a grain of sweat and body oils to it, right?

MOA? I LAFF at MOA.