Brainstorming 6.5 CM Load Improvements

[Cole440]

Ok, this story can have a ton of details. I think I will go ahead and give a summary and see what the people think.

I have a rifle in 6.5 CM and have worked up a load for it.

The very first thing I shot was some reloads in S&B brass, loaded with a random charge of H100V at book length. Right out of the gate, I had a 5 shot group of less than a half inch. I was pleased.

Since then I have worked up a load with SIG brass (that's what I could get in 2021), H4350, and the 142 SMK. I first began with chrono testing and found the velocity node. I was having good solid velocities with very decent SD and ES numbers so I decided to go with that powder charge and then adjust my OAL to bring in the group size.

I did that and got the results. I was not as impressed as I hoped I would be. I did get a couple of good groups in the sub-half inch range, but the majority of them were closer to an inch. The results seemed a little erratic, which surprised me based on how consistent the numbers from the chrono were.

Based on that info, I am kind of spitballing that the powder charge seems to be working and that some of the inconsistent results may be at least partially attributable to the brass, either in neck tension, thickness, volume, etc... I haven't checked that yet because it is all loaded at the moment and I haven't had a chance to shoot in a while.



My gut instinct at this point is (now that more options are available) to get a box of Lapua or Alpha brass and go from there. I could try to vary powder or bullet selection, but both H4350 and the 142 SMK are proven performers so I hate to try that first. In any case, I think upgrading the brass would be a good idea anyway, guess I'm just looking for validation!

 

[Yondering]

You could certainly buy different brass, but you can get good results by sorting what you have by weight, maybe neck turning for consistency if needed, and controlling shoulder bump and neck tension through consistent annealing and sizing die adjustments. Depends how much you want to work with what you have vs just buy something different hoping for better results. You'll have to do the second part of what I said above anyway, regardless of the brass used.

For me, I mostly use Hornady brass; I bought enough of it that I could sort it and keep the pieces inside a certain weight range. (It's been a while so I don't remember what that range was, but want to say +/- 1gr). Then I turned the necks ( only has to be done once, and I do it on a lathe so it's pretty quick and easy). That brass gives me some great results. Using the same process I also have a bunch of old 7.62 brass, some LC but mostly TW 68 and TW 67, that I converted to 6.5 Creed back when brass was really hard to get; it's heavier brass so the loads are different but with sorting, turning, and careful control of the dimensions it also gave me very good results.

 

[Erigli]

Ok, this story can have a ton of details. I think I will go ahead and give a summary and see what the people think.

I have a rifle in 6.5 CM and have worked up a load for it.

The very first thing I shot was some reloads in S&B brass, loaded with a random charge of H100V at book length. Right out of the gate, I had a 5 shot group of less than a half inch. I was pleased.

Since then I have worked up a load with SIG brass (that's what I could get in 2021), H4350, and the 142 SMK. I first began with chrono testing and found the velocity node. I was having good solid velocities with very decent SD and ES numbers so I decided to go with that powder charge and then adjust my OAL to bring in the group size.

I did that and got the results. I was not as impressed as I hoped I would be. I did get a couple of good groups in the sub-half inch range, but the majority of them were closer to an inch. The results seemed a little erratic, which surprised me based on how consistent the numbers from the chrono were.

Based on that info, I am kind of spitballing that the powder charge seems to be working and that some of the inconsistent results may be at least partially attributable to the brass, either in neck tension, thickness, volume, etc... I haven't checked that yet because it is all loaded at the moment and I haven't had a chance to shoot in a while.



My gut instinct at this point is (now that more options are available) to get a box of Lapua or Alpha brass and go from there. I could try to vary powder or bullet selection, but both H4350 and the 142 SMK are proven performers so I hate to try that first. In any case, I think upgrading the brass would be a good idea anyway, guess I'm just looking for validation!

For what it’s worth, my 24” barrel Havak HIT doesn’t like the SMKs. It loves the Berger hybrid and Hornady ELDM though. That being said these are all factory loaded Federal Premium Gold Medal rounds.

 

[Cole440]

Funny you should mention that. This is my second time working up a load with the smk. I was just not that impressed with what I had going on last time.

This is a pretty solid rifle in my opinion. No reason it shouldn’t shoot. For example with the 120 SMK I was shooting under half inch with random mag length loads no problems. But these 142s don’t seem to be as forgiving.

I have 500 so I wanted to make them work but maybe I should try something else too. For context this is what I’m running.

Bighorn Origin
Criterion 26” barrel with a little bastard brake
Grayboe stock
Viper PST Gen II
Triggertech special

Alpha small primer brass (annealed every time, bumped about 2 thou)
H4350
Remington 7 1/2 BR primers

Just to give you an idea what I’m working with.

 

[RegionRat]

The important takeaway, is not to stare at the chronograph data or play with calculating things like SD on tiny samples.

Your hardware and recipe seem to be fine. If your technique on the bench is up to the task, you may find a little more signal than noise. If your technique isn’t good, it can all be noise.

Also keep in mind, with a high quality rig, using high quality components for known Pet Loads, you can just about pick any charge/depth and do decent. With some skill, you may be able to exploit a characteristic and shoot a smaller group that gives you a better margin of error.

The smallest group in a given session is one thing. Getting a consistent POI and DOPE after several sessions is another goal for preloaded ammo and takes work too.

I have a feeling you will get there. Study the targets, not the chrono.

 

[BuildingConceptsllc]

I shoot the 130 Berger otm. It's way easier to get shooting excellent and you just run it faster and you aren't missing anything from a heavier bullet. Jmo

 

[Bbracken667]

Ok, this story can have a ton of details. I think I will go ahead and give a summary and see what the people think.

I have a rifle in 6.5 CM and have worked up a load for it.

The very first thing I shot was some reloads in S&B brass, loaded with a random charge of H100V at book length. Right out of the gate, I had a 5 shot group of less than a half inch. I was pleased.

Since then I have worked up a load with SIG brass (that's what I could get in 2021), H4350, and the 142 SMK. I first began with chrono testing and found the velocity node. I was having good solid velocities with very decent SD and ES numbers so I decided to go with that powder charge and then adjust my OAL to bring in the group size.

I did that and got the results. I was not as impressed as I hoped I would be. I did get a couple of good groups in the sub-half inch range, but the majority of them were closer to an inch. The results seemed a little erratic, which surprised me based on how consistent the numbers from the chrono were.

Based on that info, I am kind of spitballing that the powder charge seems to be working and that some of the inconsistent results may be at least partially attributable to the brass, either in neck tension, thickness, volume, etc... I haven't checked that yet because it is all loaded at the moment and I haven't had a chance to shoot in a while.



My gut instinct at this point is (now that more options are available) to get a box of Lapua or Alpha brass and go from there. I could try to vary powder or bullet selection, but both H4350 and the 142 SMK are proven performers so I hate to try that first. In any case, I think upgrading the brass would be a good idea anyway, guess I'm just looking for validation!

Do you anneal? If you do not that could contribute to some inconsistency in neck tension.
Regarding Lapua brass I highly recommend it. Great brass.

 

[Bbracken667]

I agree with the Berger and ELD options.
Something else to consider is hBn. Very cheap, simple and safe. I have been impressed with it and it is so barrel friendly. I swear it reduces copper and carbon buildup, but that is just an impression, not proven in any scientific way.
Consistency is important. The fact you are pleased with MV consistency but precision results not so much, I would suggest trying longer shooting ranges and also look at your shooting MO. Other things too look at is case prep, particularly neck tension. Scale consistency is critical. Bullet seating can possibly affect precision.
I feel like I am stating the obvious but sometimes reminders of the known can help get creative juices going.
Best of luck in your journey!

 

[kthomas]

FYI, there is no velocity "node".

The best way to get excellent results is to use excellent components. Like Lapua brass and Berger projectiles.

 

[Bbracken667]

FYI, there is no velocity "node".

The best way to get excellent results is to use excellent components. Like Lapua brass and Berger projectiles.

I would say that excellent methods are critical. Methods, materials and shooting discipline are all critical to achieving results.
I agree with the lapua and would probably use more Berger but the are just so irregularly available

 

[kthomas]

I would say that excellent methods are critical. Methods, materials and shooting discipline are all critical to achieving results.
I agree with the lapua and would probably use more Berger but the are just so irregularly available

Yeah getting components can be tricky.

 

[Bbracken667]

Yeah getting components can be tricky.

I feel very fortunate to have been able to buy 200 6.5 cm large rifle primer cases, along with 2000 large rifle cci BR2 primers and 200 140 grain eld m’s in the last couple weeks. I just don’t know what to expect going forward with Ukraine etc going on. I suspect we need to make hay while the sun shines. Clouds may be coming

 

[Cole440]

Thanks for all the insights. I believe that I’ve ironed out all of the components for this group.

At this point since I know where the velocity starts to hit pressure. I think I’ll load up some groups in the area I’m trying to be in and out it on paper and see what it looks like.

As they say, the target doesn’t lie. After that I can mess with seating depth if it becomes necessary.

 

[Bbracken667]

The important takeaway, is not to stare at the chronograph data or play with calculating things like SD on tiny samples.

Your hardware and recipe seem to be fine. If your technique on the bench is up to the task, you may find a little more signal than noise. If your technique isn’t good, it can all be noise.

Also keep in mind, with a high quality rig, using high quality components for known Pet Loads, you can just about pick any charge/depth and do decent. With some skill, you may be able to exploit a characteristic and shoot a smaller group that gives you a better margin of error.

The smallest group in a given session is one thing. Getting a consistent POI and DOPE after several sessions is another goal for preloaded ammo and takes work too.

I have a feeling you will get there. Study the targets, not the chrono.

Excellent comment! I like the “noise” descriptor and seems appropriate.
When load developing after my first run at the range I will verify my best on the second trip. Duplicating results is important, otherwise it’s just noise.

 

[Doom]

Some of the best advice on this thread is contained in @RegionRat's post. In popular cartridges you can just about guarantee that there are known loads/combinations of components and powders that will work for you. As for the chronograph, leave it in the closet. Let the target tell you what works. The whole concept of flat spots in the velocity/charge weight doesn't work for numerous reasons. Trying to pick a low SD requires more shots per charge than you would want to shoot. I takes about 20 to 30 shots to get a good handle on the SD of a load. After you have a consistent point of impact you can get the Crony out and see what your SD is and work on improving your reloading techniques.

 

[Cole440]

So as far as starting out, how would do you guys prefer to settle in on a load? Group, impact height? what say you?

 

[Doom]

So as far as starting out, how would do you guys prefer to settle in on a load? Group, impact height? what say you?

You've asked a question that has multiple answers and to me the ultimate answer may not be the starting answer. An F-class or Benchrest shooter is going to probably answer differently. It sounds like you may be somewhat of a novice reloader and shooter. First off I would recommend that you read up on Dan' Newberry's OCW method. It may not be the way you want to go but it is a system and it works. it works of finding charges with similar paints of impact. Shooting groups and making a determination from 3 or 5 shot group sizes can work but it relies on a repeatable accurate shooter and rifle. You need to determine what you want to achieve and find a load that meets that goal. Don't fall into the "I want to shoot the smallest group possible" syndrome.

Good Luck.

OCW Site

Home

 

[Cole440]

I appreciate the info!

I am familiar with the OCW method and the various ways people like to work things up. I am certainly now a new shooter/reloader HOWEVER, I am inexperienced in the world of precision. I have only been messing with precision stuff for a couple years here and there. Now that I finally got all of the equipment and supplies that I wanted I am really ready to try some different methods to try and get the best that I can squeeze out of this setup!

I was just looking for anybody's superstitious tips that work for them haha. Like I said, the huge test over the chrono was more to find velocities and experiment rather than looking for a velocity node etc.

It's great to have a ton of experienced folks to run things past here!

 

[Baron23]

Shooting groups and making a determination from 3 or 5 shot group sizes can work but it relies on a repeatable accurate shooter and rifle.

And, so does OWC, does it not? A shooter can pull any shot and skew the results. It seems to me that unless the gun is mounted to a 200 lbs concrete block, trying to take the shooter out of LD results is always a challenge no matter the method used.

No?

 

[Bbracken667]

And, so does OWC, does it not? A shooter can pull any shot and skew the results. It seems to me that unless the gun is mounted to a 200 lbs concrete block, trying to take the shooter out of LD results is always a challenge no matter the method used.

No?

This is where the quest for precision reloading leads to the quest for improved shooting technique. I particularly enjoyed learning about zero force final firing position. The key to resolving at least half of what you mentioned above.

 

[mike278]

Serious question about the OBT method: can you use Quickload's barrel time numbers to get you in the ballpark as far as powder/seating depth(OAL)/charge weight to get you in the ballpark, or is it about as good as guessing a starting point?

 

[Doom]

And, so does OWC, does it not? A shooter can pull any shot and skew the results. It seems to me that unless the gun is mounted to a 200 lbs concrete block, trying to take the shooter out of LD results is always a challenge no matter the method used.

No?

Quick answer is yes. But shooting round robin helps (sometimes hurts group size) and most nodes tend to be 2 to 3 charge increments wide. It's less likely to result in chasing a single small group that may not be repeatable. It's not perfect but seems to work. What I have found with OCW is that most shooters will shoot a string (range of loads) and then get off the rifle to let the barrel cool. When they get back on the rifle the string POI will shift but will tend to stay shifted for the entire string so the groups open up but average POI for the strings tends to follow. Now if you can't repeat from shot to shot in a string then it becomes a real problem.

Serious question about the OBT method: can you use Quickload's barrel time numbers to get you in the ballpark as far as powder/seating depth(OAL)/charge weight to get you in the ballpark, or is it about as good as guessing a starting point?

Good question. Dan Newberry worked with Chris Long and seemed to buy in on it. Personally I have not used Quick Load but have used Gordan's Reloading Tool which has an OBT in it. When I have run the OBT on some of my loads it puts me in the ballpark. It is sensitive to the powder model and also to fired case volume. GRT has a module that uses actual measured velocity with the model to calculate an actual OBT adjustment. I did use it on a recent load where I wanted to increase a known 223 load to a higher velocity to match a similar load (different powder, 8208 and N135, and bullet, 53 SMK and 52 Burger Match Target, and it worked.

 

[Bbracken667]

A huge part to achieving consistency in hand loading is shooting technique. This is an article I just love. No matter who you are, even if you know this already, it can’t hurt to revisit fundamentals occasionally. Firing position fundamentals have helped me tremendously in improving my shooting.

Precision Rifle Marksmanship - Grip Technique :: Primal Rights, Inc

No matter your rifle, sighting method, firing position, or distance to target; Grip technique is one of the most important aspects of operating a precision rifle effectively.

www.primalrights.com

 

[Bbracken667]

Here is another fundamentals article. I am sure most of y’all are beyond this, but sometimes just reading them, as opposed to knowing them can bring out of the box thinking in your own process which can result in minor improvements. If you are highly experienced and have achieved good results it’s likely that minor improvements are what you may be able to achieve, having picked every bit of the low hanging riper fruit.

Load Development :: Primal Rights, Inc

Precision rifles are only one part of a much larger system. You can have the most precise and accurate rifle in the world, and it will be for not without everything else being on point. The shooter must do their job by accounting for environmental conditions, breaking the shot correctly, and...

www.primalrights.com

 

[Doom]

A huge part to achieving consistency in hand loading is shooting technique. This is an article I just love. No matter who you are, even if you know this already, it can’t hurt to revisit fundamentals occasionally. Firing position fundamentals have helped me tremendously in improving my shooting.

Precision Rifle Marksmanship - Grip Technique :: Primal Rights, Inc

No matter your rifle, sighting method, firing position, or distance to target; Grip technique is one of the most important aspects of operating a precision rifle effectively.

www.primalrights.com

Where was this 14 years ago when I got back into shooting sports after a 36 year layoff!

Here is another fundamentals article. I am sure most of y’all are beyond this, but sometimes just reading them, as opposed to knowing them can bring out of the box thinking in your own process which can result in minor improvements. If you are highly experienced and have achieved good results it’s likely that minor improvements are what you may be able to achieve, having picked every bit of the low hanging riper fruit.

Load Development :: Primal Rights, Inc

Precision rifles are only one part of a much larger system. You can have the most precise and accurate rifle in the world, and it will be for not without everything else being on point. The shooter must do their job by accounting for environmental conditions, breaking the shot correctly, and...

www.primalrights.com

I don't agree with everything in this article but I'm not about to argue with Greg on the OCW method. His observation about OCW being about improving accuracy as opposed to precision is correct. It is about optimizing the system, that is the rifle, case, bullet, powder, primer to get a repeatable point of impact. From there precision becomes the focus of reloading techniques. Can a non OCW load be accurate and precise? I think its possible but I personally don't want to go there as that is not my goal.

One thing I don't like to bring up in helping new reloaders is playing with seating depth. That is not because it doesn't matter but because it can be a rabbit hole that can cloud other reloading issue. I personally recommend people work with certain known bullets that work well at published COAL's, especially with factory rifles.

 

[Bbracken667]

I totally agree. There were a couple things that I just went “huh?” at but all in all, it’s good.
I am all about zero force final firing position (ZFFFP). That has helped my shooting probably more than anything since I began this journey back in the 70’s. The internet is awesome!!

Precision Rifle Marksmanship - Zero Force Firing Position :: Primal Rights, Inc

Building your firing position is one of the most important factors of successfully operating a precision rifle. Of all the fundamental concepts which govern the precision and accuracy we can achieve with our rifles, firing position generally has the least attention paid to it and is quite...

www.primalrights.com

 

[Bbracken667]

Where was this 14 years ago when I got back into shooting sports after a 36 year layoff!


I don't agree with everything in this article but I'm not about to argue with Greg on the OCW method. His observation about OCW being about improving accuracy as opposed to precision is correct. It is about optimizing the system, that is the rifle, case, bullet, powder, primer to get a repeatable point of impact. From there precision becomes the focus of reloading techniques. Can a non OCW load be accurate and precise? I think its possible but I personally don't want to go there as that is not my goal.

One thing I don't like to bring up in helping new reloaders is playing with seating depth. That is not because it doesn't matter but because it can be a rabbit hole that can cloud other reloading issue. I personally recommend people work with certain known bullets that work well at published COAL's, especially with factory rifles.

When in doubt go with the “book” recommendations. Experiment if you feel you may benefit.