Friday, November 3, 2017

Choosing Good Factory Ammo


The topic is huge and the methods are many….  so this is just a glimpse and one attempt to help.  I reload, but have customers that don’t so I have this discussion often enough.  Figure out the intended use first of all.  Learn about projectiles and what makes one better for hunting than another or what makes one better for long range shooters than another.  Hunting at short distance may change the choice versus shooting steel at 1200 yards, or you may find a good projectile for both uses.  I’m addressing this from a view of a person that may shoot practical precision type matches, or just want to enjoy shooting steel at the range over a good long distance.   

My two main uses for long range rifles are hunting and practical precision matches, to give some idea of my bias.  I'm using 6.5 Creedmoor as my example because it's a cartridge I discuss with a lot of customers and friends these days.  The same logic applies to other cartridges though.  One main difference between the Creedmoor and some other widely used cartridges is that the Creedmoor has many good factory options available to the practical precision shooter or the hunter. 

You can narrow the field by looking at what other folks are getting good results with.  If you don’t know where to begin to look… look to the shooting sports.  You’ll find that most folks shooting practical precision matches do reload, but there are some shooters using factory ammo.  Why look at what they are using..... well first be sure you are looking at good info from a person that understands what they are talking about, but the reason is because the good shooters at these matches want to do the best they can and often do their best to remove any variable that will decrease their chance of that.  If your main use is hunting be sure to talk with good hunters that you know will share good info with you.  On my last 6.5 Creedmoor barrel I ran through 800 rounds of PRIME ammo, because I wanted the brass.   I’m going to chamber a 6 Creedmoor barrel for use on a SwitchLug rifle and it’ll only run factory ammo for those times I want to shoot a match, but don’t have, or want to make, time to load first.   I’ll have good data to share with people that want to know the ups and downs of shooting factory ammo and there are lots of other shooters that will do the same.   Not every cartridge has as many options available when it comes to factory ammo.  Be sure you are getting good projectiles that will do what you want and be sure your rifle barrel twist will make good use the projectile choice.  

Order enough of each ammo type to really get a good idea of what they will do.  You can even start with the ammo you want to use most and see if it works for you or not as opposed to ordering more than one brand at a time.  One thing to keep in mind is that your velocity is likely to change some, especially over those first 75-150 rounds.  Another thing… give yourself time to do this the right way.  These days many folks rush the process way too much. 

What are you looking for…..  this is the part that can get complicated.  It’s easy to say a good group and that’s true.  There are many ways to study a group when comparing one to another to choose what’s best.  What I would hope for is a nice group that didn’t show more than an acceptable amount of vertical dispersion from a factory load.  The amount that’s acceptable is up to you.  When you shoot factory ammo you often have to compromise.  Generally, if you get a good factory ammo you are going to deal with a slower velocity or a powder that is more temperature sensitive than you’d hope.  There are some places to buy loaded ammo that produce excellent ammo, but you’ll certainly pay for it as compared to something like a PRIME or Hornady, for example.  This is not meant to say that PRIME and Hornady are bad choices.  I think, properly understood, they can do what a lot of people need.  There are other good brands and I’m just making an example with these two. 

Besides a good grouping, you would want the best extreme spread and standard deviation possible.  Some people skip this part when they use factory ammo.  You can have an acceptable group at 100 yards and not have a good ES or SD.  It will show up further down range though, so don't think that just because you have a good group at 100 yards you are good to go.  Some folks shoot at further distance to try to verify ES and SD, but I find that to be difficult for many shooters, generally speaking.  I believe a better answer for most folks is to get with someone that has a good chrono or buy one themselves.  I prefer the MagnetoSpeed, personally.  It's a good tool at a good price and it gives excellent data.  I also like that the company is so involved in the shooting sports and how they support the sports.  The main point though, is to be sure you are using a chrono that's providing good and helpful data.  

The chrono data is going to help you choose the better ammo for your rifle and it’s also going to help you collect velocity data so you can better engage targets at distance.  It’s also going to help you collect data on temperature sensitivity so you can properly correct for it, when needed.   Earlier I mentioned that your velocity is likely to change those first 75-150 rounds, but you can have a velocity change later on and you will likely have a velocity change as your barrel begins to near the end of its effective use.   So… a good chrono is a good tool to have for many reasons.  It’s good to check velocity, ES, and SD at times throughout the life of your barrel, for many reasons.    

Once you find a good ammo for your rifle, buy as much as you can from one lot.  Continue to verify everything even within that lot, but especially verify when you buy more ammo or change lots.  When you buy your ammo, look at each cartridge individually before you head to the range or whenever you can before shooting, but verify because eventually (if you shoot much) you’ll find something wrong and you’ll be glad you culled it. 

What happens when you have tried every good ammo choice and you can’t get a good answer…. well… it’s time to figure out what’s wrong with either you or the rifle system.  If it’s you… then you know you need to learn more and practice more.  If it isn’t you, or you have eliminated you as the problem, then you begin to look at what may be wrong, or needs altered, with the rifle to get the accuracy you want.  Maybe it’s not the barrel or ammo, but it’s the stock, base, rings, or scope (etc).  Maybe you had bad mirage that day, but didn’t understand how that can cause issues.  Some things are simple and others get complicated.  This is another big topic, so I won’t go into it more with this blog entry. 

A few other things… don’t be married to these things without verifying the data yourself.  The internet lies.  Test it for yourself.  Take a good class and learn how to use all of this information properly.  A good class isn’t cheap, but neither is wasting good ammo when you don’t even know what you don’t know.  Meet good shooters in your area and learn together with them.  Put yourself to the test and learn where you are weak.  Learn to make good use of tools available and have methods that back up your tools.  Have a backup for your backup plan.   I hope this helps someone and keep in mind that this is just one thought on choosing factory ammo and there are certainly many ways to skin that cat. 





Tuesday, March 7, 2017

6mm or 6.5mm



When we discuss practical precision shooting we often get down to 6mm or 6.5mm.  There are some folks shooting in different divisions or folks that just want to shoot 7mm, 30cal, or even some 223.  This is just meant to break down and show the differences in the two that are used the most by those top 100 competitors in the sport.  This doesn’t mean you have to choose what they do or choose for the same reasons they do.  It just means they are good at what they do and it might be worth looking into why they use what they do.
 

Velocity and Projectiles Used for Comparison

I broke these down by using a 6mm pushing a 105 Berger Hybrid and 3050 fps and a 6.5mm pushing a 140 Berger Hybrid at 2750 fps.  If you are safely able to and want to run a load that's faster in your rifle or if you want to check a different projectile, you can of course run different data for your own comparison purposes.



Basic Breakdown

Generally, we think of the 6mm as having a little less recoil and the 6.5mm as having a little better barrel life.  There is also the difference in energy on the longer shots.  So, the 6mm will be a little easier to use on barricades, but the 6.5mm will show impacts a little easier at those longer distances that we shoot.  Keep in mind that the majority of our shots are 800-900 yards and in and there aren’t as many of those longer shots out at 1200 yards or more.  Also, we are seeing more target flashers on those long distance targets and that will make it easier for ROs to spot impacts and that may push even more shooters to the 6mm side.  There are some cases that do a little better or worse for each caliber as far as velocity and barrel life.  The case and the pressure you load to will have something to do with how fast you shoot your barrel out; along with a few other things like how hard you push your rifle during a match or practice.  This is meant to be a generalized statement to explain why some folks choose 6mm and others want 6.5mm.  Also, keep in mind that when we discuss practical precision and recoil, we aren't referring to a recoil that hurts you or makes it unbearable to shoot.  Recoil, in this discussion, is meant as being easy to spot your own shots (or not), even when you are in a less than ideal shooting position.  Most shooters find it critical to be able to spot their own shots to make fast corrections.


Data Comparison

The data comparison was made using Applied Ballistics Analytics.  The custom curve was used for each of the projectiles.  The second page of data shows a hit percentage with variables introduced.  This is at 1000 yards (actually 999.563 yards).  The left hand side will show the variables that were used to get the data output.  


6mm Data





6.5mm Data




What does it mean?

First, you can look through the data for yourself and decide what it means to you.  Some of the things I notice are that the windage is very similar between the two.  Most of us consider the wind to be one of the harder factors to overcome.  Keep in mind the generalized differences that were listed above under 'Basic Breakdown'.  Often we say that the elevation isn't as important since we are able to so accurately predict that part of the equation.  There are times where the lesser drop of the 6mm is helpful.  Basically, it is more forgiving to any mistake we make or if any part of our data is off, such as distance to target.   


Another Comparison

For this blog entry I ran one more chart to compare.  Currently, I am shooting a 6.5mm that pushes a 140 Berger Hybrid at 2787 fps.  This barrel is at about 2200 rounds and hasn't shown any loss in velocity so far.  I have considered going to a 6.5 SAUM for my next barrel, but loading it 'slow' to attempt to get as good of barrel life as possible.  For this, I ran the 6.5 mm 140gr Berger Hybrid at 2950 fps.  There are folks running the 6.5 SAUM for practical precision, but I don't see it used nearly as often as the popular 6mm and 6.5mm cartridges.  I believe it would be a little more difficult to spot my own shots using this, as compared to my current choice.  

6.5mm 140gr Hybrid @ 2950 fps




When you compare the 6.5mm 140 Berger Hybrid at 2950 fps to the 6mm 105 Berger Hybrid at 3050 you see that they are very similar in both elevation and windage, with the 6.5mm carrying more energy.  This idea is appealing to me.  I'm not sure yet that I will give it a try, but the appeal is there especially if the barrel would have decent life.  

Conclusion

When you compare these things you can see why it's difficult for some folks to choose one over the other. Many shooters have a few match rifles. One person may set up a trainer in 223 that's set up similar to their match rifle. Another person may have a 6.5 SAUM for windy days or matches that concentrate more on the longer range side of things. Hopefully this data will help some folks that are looking for the basic differences between the 6mm and 6.5mm choice for practical precision.


There will be more blog entries in the future covering more long range topics. Thanks for reading and feel free to share this or my other blog entries if you think it will help someone.