Progression of a 30 Round Group

[huntnful]

This is an 11.5lb 300 Norma Mag Improved shooting 225 ELDM’s at 2920fps with H1000. Shot on 15X power, in the middle of the afternoon with some pretty decent mirage. The group was shot over the course of 2 hours via 10 separate 3 shot groups at the same aim point.

No “Load Development” was done prior. Just a steel barrel, previous knowledge with the cartridge and the same reloading practices I always use (which is even less now).

6 SHOTS




12 SHOTS




18 SHOTS




24 SHOTS




30 SHOTS




I think it’s cool to compare zero shift from 6 to 30 rounds, as well as the group size growth, which is exactly 50% larger than the initial 6 shots.

 

[Gstew1930]

thats an outstanding 30 shot group. makes it even better you had to break your position 10 times and still managed that

 

[Macintosh]

Excellent. Care to repeat with a factory-barreled rifle?
Reason I ask is the zero shift from a small group to a large group. In your case the difference is only about .1 inch, or less than the click resolution of a scope. It’ll obviously be more on a rifle shooting a group 2-3x the size.

 

[Formidilosus]

as well as the group size growth, which is exactly 50% larger than the initial 6 shots.

That is a good example of exceptional precision. However, for others- the only reason that the group only grew 50% from the first 6 shots to 30 shots, is because the baseline precision of the system. That will NOT be the case for the vast, vast majority of rifles.

 

[huntnful]

That is a good example of exceptional precision. However, for others- the only reason that the group only grew 50% from the first 6 shots to 30 shots, is because the baseline precision of the system. That will NOT be the case for the vast, vast majority of rifles.

Oh I totally agree. I bet my average 5 round group actually doubles, if not triples in size with an additional 10-20 shots.

I think in this specific case, it was just a rather large intial 6 shot group in relation to the overall precision of this larger group, so the data is skewed. Just like if the first 6 shots were .75 MOA, technically the group would have had 0% growth.

Just a one off case is all it is. Shouldn’t have honestly even mentioned it as a data point haha.

 

[Formidilosus]

Oh I totally agree. I bet my average 5 round group actually doubles, if not triples in size with an additional 10-20 shots.

I think in this specific case, it was just a rather large intial 6 shot group in relation to the overall precision of this larger group, so the data is skewed. Just like if the first 6 shots were .75 MOA, technically the group would have had 0% growth.

Just a one off case is all it is. Shouldn’t have honestly even mentioned it as a data point haha.

Nah, it’s good to see. The issue is that people try to use the AB chart of percentage increase of “x” shots in a group, to a larger number group size- but it only works if you use the average of the smaller shot group sizes. But people use only one smaller shot group size to extrapolate, or even their smallest group to do so.

 

[huntnful]

thats an outstanding 30 shot group. makes it even better you had to break your position 10 times and still managed that

Haha it’s definitely nice to know I don’t have a flinch and lay down relatively the same behind the rifle each time

Excellent. Care to repeat with a factory-barreled rifle?
Reason I ask is the zero shift from a small group to a large group. In your case the difference is only about .1 inch, or less than the click resolution of a scope. It’ll obviously be more on a rifle shooting a group 2-3x the size.

I think anyone can repeat with their own equipment for sure. Yes, a more accurate rifle can get away with less shots for a legit zero. In this specific case, I think a 10 round zero would be plenty. But I would still want a 10 shot zero, even if it’s shoot small groups. But a less accurate rifle would possibly need more, like you said.

 

[huntnful]

Nah, it’s good to see. The issue is that people try to use the AB chart of percentage increase of “x” shots in a group, to a larger number group size- but it only works if you use the average of the smaller shot group sizes. But people use only one smaller shot group size to extrapolate, or even their smallest group to do so.

I’m glad you mentioned that! Because I’ve seen that chart and it does align with a lot of my own personal data, like in this instance. But I definitely appreciate that clarification of the AVERAGE of groups. Not just one 5 shot group that’s .5 MOA, so the gun is “probably going to shoot .8 MOA for 10” or something like that. Thank you for pointing out that his data is based off large data sets and averages of those data sets.

 

[B_Reynolds_AK]

I don’t know man.. looks like your .1 to the right.

 

[huntnful]

I don’t know man.. looks like your .1 to the right.

Now that I have a legit zero, I feel comfortable making that .1 click to the left

 

[TaperPin]

…with some pretty decent mirage.

Great job. It was very interesting that you kept track of the progression - great example for anyone who hasn’t seen it first hand.

I have no doubt under ideal conditions without mirage it would group even better.

The results aren’t surprising though - a good shooting custom barrel will stack groups time after time, despite those that poo poo the idea and believe some crappy factory barrel, low end custom barrel, or top barrel with loose chamber is just as good.

 

[huntnful]

Great job. It was very interesting that you kept track of the progression - great example for anyone who hasn’t seen it first hand.

I have no doubt under ideal conditions without mirage it would group even better.

The results aren’t surprising though - a good shooting custom barrel will stack groups time after time, despite those that poo poo the idea and believe some crappy factory barrel, low end custom barrel, or top barrel with loose chamber is just as good.

I think it is mostly attributed to the whole build itself as well. My personal beliefs at this point for consistent accuracy in builds now goes like this, in sequence of importance.

1. Enough weight to actually manage the recoil of the cartridge the build is intended for, with 8.5lbs being the bare minimum for any rifle I’ll personally own just from a stability standpoint.

2. Properly bedded action.

3. Barrel quality from tip to tail

4. Chamber quality

5. Stock fitment/design

Then just top it with a dependable scope pretty much.

I’m also very open to hearing what other place things on levels of importance based off personal experiences.

 

[mxgsfmdpx]

Not correcting the .1 MIL is giving me anxiety.

Nice shooting and excellent precision!

 

[Zdub02]

It will KEEL!

 

[huntnful]

Not correcting the .1 MIL is giving me anxiety.

Nice shooting and excellent precision!

Hahaha I don’t like correcting in the middle of the group. But spoiler alert. This is brand new rifle lol. I bore sighted it, used 3 shots on a blank piece of paper to get a rough zero and then went straight up to the 30 round group. So what you see is shots #4-33 down the barrel.

This is a .75 MOA 30 round group… just forming brass lol. From 300 Norma Mag, to 300 Norma Mag Improved 35 degree shoulder.

 

[TaperPin]

I think it is mostly attributed to the whole build itself as well. My personal beliefs at this point for consistent accuracy in builds now goes like this, in sequence of importance.

1. Enough weight to actually manage the recoil of the cartridge the build is intended for, with 8.5lbs being the bare minimum for any rifle I’ll personally own just from a stability standpoint.

2. Properly bedded action.

3. Barrel quality from tip to tail

4. Chamber quality

5. Stock fitment/design

Then just top it with a dependable scope pretty much.

I’m also very open to hearing what other place things on levels of importance based off personal experiences.

I like your list. I’d add a high quality trigger as essential. At one time I had two 7 mag rifles more or less identical with good bedding, reliable scopes, and same weight of trigger pull, and a few hundred rounds on paper so the accuracy of each was well known. The triggers were reworked factory triggers set at 2 lbs and there was a very slight amount of creep in each. As each rifle’s trigger was replaced with a higher quality aftermarket model of identical pull weight, groups decreased almost 1/4 moa. At least for me and my shooting style, from the bench or field positions, a flawless trigger is a must have.

With hunting weight rifles, I’ve been asking for the past year if anyone has an accurate well bedded rifle and changed stock designs with a noticeable change in accuracy. It’s been hard to get even a sliver of hard data that the latest stock designs are making a major improvement over even a classic style stock with add on cheekpiece for proper cheekweld. There must be tangible benefits, albeit somewhat small - some European target stocks of the 1960’s and 1970’s look very much like modern designs yet they didn’t really gain traction for decades, even when shot side by side with more classic designs.

 

[Antares]

How do you mark shots in the app when they go into the existing hole from previous shots? Just guess? I mark shots around the perimeter and then just randomly place the rest of the shots in the hole, but I’ve wondered whether this affects the metrics the app spits out. Is there a better method?

 

[huntnful]

How do you mark shots in the app when they go into the existing hole from previous shots? Just guess? I mark shots around the perimeter and then just randomly place the rest of the shots in the hole, but I’ve wondered whether this affects the metrics the app spits out. Is there a better method?

Yes sir that’s all I did. Nothing precise as far as dropping the shots in the voided area of the group. I just make sure each group has the correct amount of shots displaced evenly throughout it is all.

I like your list. I’d add a high quality trigger as essential. At one time I had two 7 mag rifles more or less identical with good bedding, reliable scopes, and same weight of trigger pull, and a few hundred rounds on paper so the accuracy of each was well known. The triggers were reworked factory triggers set at 2 lbs and there was a very slight amount of creep in each. As each rifle’s trigger was replaced with a higher quality aftermarket model of identical pull weight, groups decreased almost 1/4 moa. At least for me and my shooting style, from the bench or field positions, a flawless trigger is a must have.

With hunting weight rifles, I’ve been asking for the past year if anyone has an accurate well bedded rifle and changed stock designs with a noticeable change in accuracy. It’s been hard to get even a sliver of hard data that the latest stock designs are making a major improvement over even a classic style stock with add on cheekpiece for proper cheekweld. There must be tangible benefits, albeit somewhat small - some European target stocks of the 1960’s and 1970’s look very much like modern designs yet they didn’t really gain traction for decades, even when shot side by side with more classic designs.

My last stock sucked balls. Was way too short and had a shitty design IMO. I shot an honest 1/4 MOA 5 shot group at 600 yards with that stock. I don’t believe the stock makes any significant difference as far as sheer accuracy from a bench. But can certainly make a difference for shoot-ability, recoil management and spotting hits in field scenarios.

 

[Harvey_NW]

That's insane. 3/4 MOA legit 30 shot group with a fireforming load. Your gunsmith is about to be welcomed to a shit show!

 

[ScreamingPotato]

Come on OP, everybody knows nobody can shoot groups like that with a 30 caliber because you flinch.