25 Round groups as Proof

[bruceleroy]

I'll be a brief as possible, but...


Facts:
Sig Cross 6.5 Creedmoor (started as 308, shot the barrel out), MDT Grnd-Pod bipod, Vortex PST G2 3-15x44, Warne Hyperlite rings
Starline brass
140 ELD-M
CCI Primers
Brass was once fired, annealed, full length sized with no expander ball, 0.263 expander mandrel for neck size
CBTO 2.214 and 2.220
25 round groups with each as well as 2 different muzzle brakes

Obviously seeing some of the posts here, reading a lot on other reloading forums and long range forums the waters/science of reloading can get muddy.

I began reloading for my newly barreled Cross with a factory new take off barrel sold by Straight Jacket Armory. I did the install and torqued at 50 lb/ft.

My initial reloads were not very promising as they ALL shot at about 1.5 inches at 100 yards. This would have been shots 31-75 through this rifle.

Shots 1-30 were with 130 ELD-M and most of them shot MOA or better. Back to the 140s...

I decided that I would run at 42 grains of H4350 since it was the most consistent SD/ES of everything I tried. I then decided to do a seating depth test. All my measurements were measure CBTO.

I tested the following and results are followed with avg, ES then SD.
2.245 2615 50 26
2.242 2614 77. 42
2.239. 2610. 19. 10
2.234. 2588. 16. 9
2.229. 2593. 16. 8
2.226. 2613. 47 26
2.223. 2606. 16 8
2.220. 2593. 19. 9
2.217. 2603. 38 19
2.214. 2600. 26 14

the 2.214 shot a 5 shot group at 0.271"


The 2.220 shot a 5 shot group at 0.57"


Even though these did not represent the absolute best of SD/ES I figured I would give them a try.

After the initial firing of reloads I accumulated the means to anneal as well as an expander mandrel so I added those steps to my process. In other words, I changed stuff. I cannot be certain how much this changed the outcome of future testing but annealing and using an expander mandrel are steps that were going to be included no matter what.

After the controversial Hornady Podcast about your groups being too small: YT Video and hearing @Form on the Exo Mountain Gear Podcast talking about Cone of fire and essentially proofing/proving your accuracy, I figured I needed to do just that. This would allow me to find the balance of deficiencies between myself and my rifle, or just reaffirm that maybe I just need to be better.

I fired 25 shots of each CBTO group of cartridges and through 2 different muzzle brakes (testing for change of impact and recoil impulse). All groups were dialed high to keep the aim point clean.

Group 1: 2.214 with VG6 Gamma 7.62 Brake resulted in a 2.2" group



Group 2: 2.220 with VG6 Gamma 7.62 Brake resulted in a 1.5" group


Group 3: 2.214 with PRI/MSTN Brake resulted in a 2.1" group


Group 4: 2.220 with PRN/MSTN Brake resulted in a 1.45" group (Alibi: I was sandwiched between a guy shooting a 300 RUM and a 7 Rem Mag Braked during this grouping, I still accept the outcome)



My rhythm was load 5, take well aimed shots, not timed, reload and do it again until all 25 shots had been fired. The barrel was HOT at the end. I am sure if I waited a minute or two between each 5 shot strings my results would have been better. However, I want to know what my rifle is capable of. I think this shows that.

While some may argue that their if their rifle made a similar 0.271" group they have an MOA all day long gun, I would disagree with facts. My rifle is a 1.4-1.5 moa all day long gun and i am thrilled with that. I have the truth with data to back it.

My next steps will be to do similar testing off of a tripod, hiking sticks with Wiser Precision Quick-Stix, and a RoadRunner Rifle Rest to mimic field conditions since I rarely rely on range positions to ensure I can hunt effectively.

The end...for now.

 

[RDF1]

Very nice example.

What i started doing is setup my rifle and shoot it only once a day at 100 yards. Every day about noon id go out and only fire one round and over 10 days average them together or see if there was a pattern.
I used the Larue targets that have 2 aiming spots with 1/2" grids. Had 5 of those targets setup and it was interesting for sure.

 

[KyleR1985]

I'll be a brief as possible, but...


Facts:
Sig Cross 6.5 Creedmoor (started as 308, shot the barrel out), MDT Grnd-Pod bipod, Vortex PST G2 3-15x44, Warne Hyperlite rings
Starline brass
140 ELD-M
CCI Primers
Brass was once fired, annealed, full length sized with no expander ball, 0.263 expander mandrel for neck size
CBTO 2.214 and 2.220
25 round groups with each as well as 2 different muzzle brakes

Obviously seeing some of the posts here, reading a lot on other reloading forums and long range forums the waters/science of reloading can get muddy.

I began reloading for my newly barreled Cross with a factory new take off barrel sold by Straight Jacket Armory. I did the install and torqued at 50 lb/ft.

My initial reloads were not very promising as they ALL shot at about 1.5 inches at 100 yards. This would have been shots 31-75 through this rifle.

Shots 1-30 were with 130 ELD-M and most of them shot MOA or better. Back to the 140s...

I decided that I would run at 42 grains of H4350 since it was the most consistent SD/ES of everything I tried. I then decided to do a seating depth test. All my measurements were measure CBTO.

I tested the following and results are followed with avg, ES then SD.
2.245 2615 50 26
2.242 2614 77. 42
2.239. 2610. 19. 10
2.234. 2588. 16. 9
2.229. 2593. 16. 8
2.226. 2613. 47 26
2.223. 2606. 16 8
2.220. 2593. 19. 9
2.217. 2603. 38 19
2.214. 2600. 26 14

the 2.214 shot a 5 shot group at 0.271"
View attachment 811224

The 2.220 shot a 5 shot group at 0.57"
View attachment 811225

Even though these did not represent the absolute best of SD/ES I figured I would give them a try.

After the initial firing of reloads I accumulated the means to anneal as well as an expander mandrel so I added those steps to my process. In other words, I changed stuff. I cannot be certain how much this changed the outcome of future testing but annealing and using an expander mandrel are steps that were going to be included no matter what.

After the controversial Hornady Podcast about your groups being too small: YT Video and hearing @Form on the Exo Mountain Gear Podcast talking about Cone of fire and essentially proofing/proving your accuracy, I figured I needed to do just that. This would allow me to find the balance of deficiencies between myself and my rifle, or just reaffirm that maybe I just need to be better.

I fired 25 shots of each CBTO group of cartridges and through 2 different muzzle brakes (testing for change of impact and recoil impulse). All groups were dialed high to keep the aim point clean.

Group 1: 2.214 with VG6 Gamma 7.62 Brake resulted in a 2.2" group
View attachment 811226
View attachment 811227

Group 2: 2.220 with VG6 Gamma 7.62 Brake resulted in a 1.5" group
View attachment 811228

Group 3: 2.214 with PRI/MSTN Brake resulted in a 2.1" group
View attachment 811229View attachment 811230

Group 4: 2.220 with PRN/MSTN Brake resulted in a 1.45" group (Alibi: I was sandwiched between a guy shooting a 300 RUM and a 7 Rem Mag Braked during this grouping, I still accept the outcome)
View attachment 811231


My rhythm was load 5, take well aimed shots, not timed, reload and do it again until all 25 shots had been fired. The barrel was HOT at the end. I am sure if I waited a minute or two between each 5 shot strings my results would have been better. However, I want to know what my rifle is capable of. I think this shows that.

While some may argue that their if their rifle made a similar 0.271" group they have an MOA all day long gun, I would disagree with facts. My rifle is a 1.4-1.5 moa all day long gun and i am thrilled with that. I have the truth with data to back it.

My next steps will be to do similar testing off of a tripod, hiking sticks with Wiser Precision Quick-Stix, and a RoadRunner Rifle Rest to mimic field conditions since I rarely rely on range positions to ensure I can hunt effectively.

The end...for now.

I got excited for a minute thinking you shot all 10 CBTO lengths for 25 rounds haha!


Good info thanks for sharing

 

[eoperator]

Facts:
Sig Cross (started as 308, shot the barrel out)

That's impressive!

 

[bruceleroy]

I got excited for a minute thinking you shot all 10 CBTO lengths for 25 rounds haha!


Good info thanks for sharing

I'm not a rich man, sometimes I pretend to be though

 

[bruceleroy]

That's impressive!

Unfortunately it did not take thousands of rounds. It lost all the accuracy around 2,800 rounds

 

[Packmansion]

Love your post! We need more like this!

 

[SDHNTR]

I wanna know how you shot out a .308 barrel in a bolt gun?

 

[bruceleroy]

I think I just got a shit barrel. It was hard to nail down from the start. Very inconsistent until about 500 rounds. Since then I have switched to a 6.5 barrel and can shoot 25-50 round 1.5" groups from the prone.

ETA: I did shoot out a 308 barrel in my Ruger American. Somewhere north of 12k rounds and it opened up to a bout 2.5-3.5 inches for 30 rounds. I still hunted with it but I never shot an animal past 70 yards with it anyways.

 

[mlevimadden]

@Harvey_NW seems like the most solid example to-date of a valid seating depth test having an effect.

 

[Packmansion]

I have a rifle right now struggling to get 10 shot groups below 1.5". Its driving me crazy. Its accurate enough to consistently hit a 10" out at 600 yards but dang. I just want smaller groups! Ive already put over 150 rounds through it. Can't quite figure out if there's something wrong or the barrel is meh. The hard thing is when you have guns that print much smaller, sometimes you just have to accept the limitations of the setup lol. It was sure nice back when we were all shooting 3 shot groups and we all had 0.5 moa rifles lol.

 

[bruceleroy]

I have a rifle right now struggling to get 10 shot groups below 1.5". Its driving me crazy. Its accurate enough to consistently hit a 10" out at 600 yards but dang. I just want smaller groups! Ive already put over 150 rounds through it. Can't quite figure out if there's something wrong or the barrel is meh. The hard thing is when you have guns that print much smaller, sometimes you just have to accept the limitations of the setup lol. It was sure nice back when we were all shooting 3 shot groups and we all had 0.5 moa rifles lol.

I miss living in my old ignorant state

 

[Q_Sertorius]

I have a rifle right now struggling to get 10 shot groups below 1.5". Its driving me crazy. Its accurate enough to consistently hit a 10" out at 600 yards but dang. I just want smaller groups! Ive already put over 150 rounds through it. Can't quite figure out if there's something wrong or the barrel is meh. The hard thing is when you have guns that print much smaller, sometimes you just have to accept the limitations of the setup lol. It was sure nice back when we were all shooting 3 shot groups and we all had 0.5 moa rifles lol.

What factors have you tried changing?

If you are getting 10-shot 1.5” groups with factory ammo, then I would expect that reloading could cut those groups in half without too much effort.

 

[Packmansion]

What factors have you tried changing?

If you are getting 10-shot 1.5” groups with factory ammo, then I would expect that reloading could cut those groups in half without too much effort.

This is reloaded ammo. Both 140 eldm and 143 eldx. It is also with a McGowen barrel with a tikka lite contour, hand lapped and im running an aero precision 3 port brake. Its a 20" 6.5 creedmoor. Tikka action. Talley lightweight rings and a vortex viper hd. If it is not the barrel the biggest culprit is scope then stock or rings. I still need to sand out the barrel channel. I am going to mount another scope with a Pic rail and seeking rings and see if that does anything. The action is for sure locked into the lug.

 

[Q_Sertorius]

I’d blame the barrel unless your reloading process isn’t sound. What kind of groups did you get with factory ammo?

 

[mtnbound]

This is reloaded ammo. Both 140 eldm and 143 eldx. It is also with a McGowen barrel with a tikka lite contour, hand lapped and im running an aero precision 3 port brake. Its a 20" 6.5 creedmoor. Tikka action. Talley lightweight rings and a vortex viper hd. If it is not the barrel the biggest culprit is scope then stock or rings. I still need to sand out the barrel channel. I am going to mount another scope with a Pic rail and seeking rings and see if that does anything. The action is for sure locked into the lug.

What is your accuracy goal for 10 rounds?

I wouldn't say that 1.5" groups for 10 rounds is bad; it's the reality of shooting larger groups. Day-to-day variables will impact your results, so you can spend a lot of time and energy shrinking your groups only to have them get bigger because of a little bit more wind at the range on that day.

 

[SupressYourself]

I'm not trying to be critical of your test. It's certainly "valid", but I'm wondering in what real-world scenarios is it "relevant"? Are you trying to determine the precision potential of the rifle, or of the rifle + you?

Other than running a test like this, when are you plopping down to shoot 25 rounds straight?
Every barrel is going to wander a bit as it gets hot, and every shooter gets some degree of fatigue, even with a low-recoil rifle.

I would be willing to bet that if you strapped that rifle into some sort of mechanical fixture and had it shoot 1 round every few minutes, the 25-round group would be much smaller.

Maybe that's not what you're interested in, and that's fine, but then what is it?

 

[MSPharm]

Thanks for posting, more evidence showing we need to shoot bigger groups.

 

[ResearchinStuff]

Unfortunately it did not take thousands of rounds. It lost all the accuracy around 2,800 rounds

that's probably when the internals on your scope crapped out.

 

[Harvey_NW]

@Harvey_NW seems like the most solid example to-date of a valid seating depth test having an effect.

I won't deny that these are much more valid sample sizes, the results seem to fall outside the predicted variability, and it seems the change had an effect in both samples. However, this is the first example I've seen on the entire internet, and to me personally the groups look like they have some stringing and are not stabilized. Maybe in that specific barrel .006" of change in jump actually made a difference.

Other than running a test like this, when are you plopping down to shoot 25 rounds straight?

The point is not the shot string, it's the sample size to see the actual precision potential, and cone of fire. It takes a lot more rounds than most people think.

Every A shitty barrel is going to wander a bit as it gets hot, and every shooter gets some degree of fatigue, even with a low-recoil rifle.

FIFY. Read this.