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USAF Ret

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So, really my first time getting a good test done on ammo. Results were mixed. Would like your thoughts. I would just load the one with the best group.

The one with the star beside it I had a flyer. Think it was me.


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Sorry, rechecked my groups and mixed a few numbers. Updated groups below for each load.

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I can't give a definitive answer,but I have a hunch.

How many shots per group? I'm generally guilty of 5 round groups but that can be misleading. Run another series and the ranking may change. Sample size matters.

I assume its a lever gun. Those groups are good for lever gun technology.

At 30-30 practical hunting ranges, does a .75 MOA group matter over a 2.5 in group?

Remember, from point of aim to point of impact is the radius of the group,not the diameter. Its (pretty much) 1/2 the group size.

So a 2 1/2 in group will shoot within 1 1/4 on of point of aim.

In the field,pointing at a deer, I'm not a good enough shot to notice.

You have good hunting rifle accuracy. You already cannot blame a miss on the gun.

Sure,pursuit of accuracy is good, So is perspective. Two piece stock? Mag tube hung on the barrel? Match bullets? Its not the foundation for a sub MOA gnat castration tool.

Thats very good hunting accuracy for a lever deer rifle.

How are your boots and sox ? Knife sharp? Range estimation? I'm suggesting you can worry about other things. Gun/ammo is good.
 
The spread of average velocities is only 16 fps from 36.6 grains to 37 grains, and only 6 fps from 36.7 grains to 37 grains. Not much difference at all, especially compared to the extreme spreads you have at each test weight. I can't imagine the difference in average velocity having much of an effect on accuracy; I'd suspect other factors. Anyway, it looks like acceptable accuracy for a hunting rifle.

It appears that you are using Hornady load data for the 37 grain maximum powder charge. The Hodgdon maximum is 35.5 grains and they list it as a compressed load. With mixed brass, are you seeing any noticeable variation in fill or compression with your charge weights?

Also, what are powder scale or measure are you using that allows a 1/10 grain step in charge weight? My equipment only resolves within 1/10 of a grain, so I have to use steps of at least several tenths to ensure an actual difference between each load.

That's my 2 cents. ;)
 
These were 50 yard groups. Marlin 336 with a 1-6x32 LPVO.

It is Hornady data. No case deformation or primer issues with max load.

I am thinking, if I can actually find any, getting some brass from all same manufacturer.

The powder charger/scale I am using is the Gucci RCBS automajic charger. I also checked every few loads on another scale to make sure they were the same. Had to reset the scale once.
 
This is a superficial comparison between the group sizes and the brass used - the best groups at 36.7 grains used only two brass types, 4 Federal and two Winchester. The second groups at 36.8, 36.9 and 37 grains also used only two different headstamps. So simple conclusion is mixed brass = fair groups, same brass = better groups. Sorting the brass and using just one headstamp at each load step may eliminate one variable in your accuracy testing.
 
This is a superficial comparison between the group sizes and the brass used - the best groups at 36.7 grains used only two brass types, 4 Federal and two Winchester. The second groups at 36.8, 36.9 and 37 grains also used only two different headstamps. So simple conclusion is mixed brass = fair groups, same brass = better groups. Sorting the brass and using just one headstamp at each load step may eliminate one variable in your accuracy testing.
Yes sir. I will be sorting and retesting. Thank you!
 
Well, I ordered 50 pieces of PPU brass to run the same test.

Dang it if this ain't enjoyable. I have chronic headaches from neck surgery (and stress, I am told). Only three things seem to make them fade away; reading my Bible, reloading and shooting.
 
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Interesting information, showing what you're getting from your rifle with your components. Other than general similarities, someone else running the same test will be using a different rifle, and different components, even if they are the same case headstamp, bullets, powder and primers they will almost certainly be from different mfg lots, and variances will occur.
 
Glad you're having fun. But in my opinion, you will get better results if you change a few things. First, the case is not the first thing most folks look at. If you are shooting competition, yes. But for a hunting rifle, at best, most of us would settle on one good one and go on. In practice, using mixed headstamps is pretty common.

When working up loads, back off further from the max, and increase the increments. Many use half grain steps; I've gone to 1%. You are running a bit faster than Hornady's max. Me, I would pick one headstamp and run 35.8 to 37.0 in 0.4 increments. Some would say back off more, but this is a low pressure round anyway. You may find a "sweet spot" for accuracy.

I have found the biggest factor after me and the rifle, is bullet selection. You already have your bullet, and for good reason. Just optimize the powder charge, then mess with headstamps. Oh, and go to 100 yard groups. That makes it easier to sort things out.
 
As 44AMP correctly stated, variances occur with the same components. Variances are the devil in reloading. Have never used mixed brass. Different manufacturers have different volume. In my experience, the smallest SD and ES have always given the best results; however, my lone lever, a 45 Colt, prints 2" at 50 yards. Levers don't give the consistent lockup of a bolt. If I had a 30-30 that printed under 2", I'd be happy.
 
36.7 is a lot better than any of the others. I would concentrate on that one and get all the brass to match. Shoot 3 shot groups and measure those.
 
USAF Ret,

I think you have the right bullet and powder combination.
In my Marlin 336 XLR, it performed much better than any other powder-bullet combination by a long shot.

I hate to say it, but one group doesn't tell you much because 'shooter induced variation' could mask the differences in the actual group sizes even more than the variation in powder load or brass source. If you are shooting with open sights, the chances for variation are greatly increased. Use a stable front and rear rest to minimize set up variations.

If you think you have found a good powder charge, shoot at least 4 5-round groups and calculate the standard deviation among those groups. Sorting your brass will take one more variant out of the mix.
If the SD is more than 0.1 you can't make any conclusions because the variation is too large (probably caused by set up inconsistency - I had the same problem so don't feel like the Lone Ranger). In reality, any one of the 4 groups may be your median group size. You might only find that out by shooting more than 20 groups for a statistically valid sample.

Trigger time with your rifle and becoming very aware of your set up process while using a stable rest will help you get it under control. There is a reason that custom rifle manufacturers use solid test fixtures when shooting test targets. It takes the shooter out of the equation.
 
USAF Ret,

I think you have the right bullet and powder combination.
In my Marlin 336 XLR, it performed much better than any other powder-bullet combination by a long shot.

I hate to say it, but one group doesn't tell you much because 'shooter induced variation' could mask the differences in the actual group sizes even more than the variation in powder load or brass source. If you are shooting with open sights, the chances for variation are greatly increased. Use a stable front and rear rest to minimize set up variations.

If you think you have found a good powder charge, shoot at least 4 5-round groups and calculate the standard deviation among those groups. Sorting your brass will take one more variant out of the mix.
If the SD is more than 0.1 you can't make any conclusions because the variation is too large (probably caused by set up inconsistency - I had the same problem so don't feel like the Lone Ranger). In reality, any one of the 4 groups may be your median group size. You might only find that out by shooting more than 20 groups for a statistically valid sample.

Trigger time with your rifle and becoming very aware of your set up process while using a stable rest will help you get it under control. There is a reason that custom rifle manufacturers use solid test fixtures when shooting test targets. It takes the shooter out of the equation.
Thanks. My rest setup is stable. I have an adjustable front rest and use a bad in the back. I have a lead sled, but I cannot get a natural shooting position using that thing.

I do see where I should be shooting 5 round groups vs. 3 based on input. Also, doing three loads vs. 5 with a bigger spread in powder charge.

Learning as I go and all inputs are much appreciated.

Setting the 30-30 aside for a but to mull over next actions. Think I may be reducing charge loads down to what Hodgdon recommends.

Going to start working 308 loads for a Sig Cross and 270 loads for a Remington Mtn Rifle. I have some powder coming in to build reduced loads as my medical issues are getting worse and the recoil is painful on higher loads.
 
Looking at all the data, I'd go with 36.8. It appears to be a node and I suspect with the same brass, that will end up being your best bet.

The thing about finding a node is that is a place where temp and powder charge variations have the least amount of influence. I still like to find a node for that reason, even for lever actions, which I get group sizes 3 to 4 times what I get in my precision rifles, but it seems to help.
 
Looking at all the data, I'd go with 36.8. It appears to be a node and I suspect with the same brass, that will end up being your best bet.

The thing about finding a node is that is a place where temp and powder charge variations have the least amount of influence. I still like to find a node for that reason, even for lever actions, which I get group sizes 3 to 4 times what I get in my precision rifles, but it seems to help.
Mark, can you PM me about the node concept? Thanks.
 
In shooting, a node is said to have been found when you identify a load that shoots tight groups and for which modest changes in load variables don't degrade the groups you shoot with it. In other words, it is a load in which small errors in powder charge or bullet seating depth or sometimes even changed powder lot numbers don't seem to cause the groups to get bigger. They tend to be more immune to temperature change than other loads, too. Simply put, it's a load sweet spot.

I don't believe you ever directly addressed HiBC's question about how many rounds were in each group. When I looked at the difference in group sizes, just based on how different some were, I guessed it was 3-shot groups. That kind of variation is expected with 3-shot groups. Then your table in post 4 confirmed it.

The problem with 3-shot groups is that for one such group in isolation, the 95% confidence level in its size accepts future 3-shot groups could be as much as almost 2.5 times bigger or as much as 0.4 times smaller than the one you just fired, 19 out of 20 times. Your 36.9 and 37.0-grain groups showed signs of that kind of range. The others could, too, if you shot more 3-shot groups with them.
 
^ Concur.

5 shot groups, for actual groups, are what I use in almost all rifles. I have one thin barrel that will only take 3 shots over a few minutes, so I keep it at 3 for that Elk rifle.
 
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