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.308 Match Ammo Comparison
Table of Contents
Introduction and Test Procedures
A while back I wrote about various match grade factory ammunition
loads that were available and described my feelings about each of them. But, that article was not
very complete and it did not provide much testing data to go off of. For a while now I have been
wanting to revisit the subject and try to provide some empirical data as well as try out several
other manufacturers 308 match ammo. I also wanted to establish a set of test procedures that were
standardized as well as a format to the article that was expandable so that I could review and add
other manufacturers ammunition to the test later without having to redo the entire review article.
Once I had set it in my mind what I wanted to do, I set out to gather all of the ammo I wanted to
test for the first go around. I wanted to stick to the 168gr class of ammo for this initial test and
figured I would open it up to other match loadings (175gr & 155gr) down the road and possibly even
other cartridges beyond the 308. I then needed to set a standard
for the tests. I wanted to take out as many of the variables as I could, but I needed to keep it
simple (not a ton of rounds or complex mechanisms like a rifle vise). Without a serious vise I know
that shooter error will come into play and I wanted to incorporate multiple shooters but ruled it out
due to the constraint it would place when we went to add new loads down the road as the chances of
getting the same shooter may be difficult. But I did settle on the fact that two rifles will be used for
the test. Both rifles are permanent fixtures with Sniper Central and the same two rifles will always be
used for future tests. More info on the rifles is provided later in this article. So, after a lot of
thought, here is the accepted test procedure for each make of ammunition.
- 1 Box of 20 rounds of ammunition will be purchased over the counter/web/mail order to insure
randomness. No factory provided ammo for testing
- 3 groups of 3 rounds will be fired from each rifle at 100 yards
- Called flyers will be noted in the results but no individual groups will be re-fired
- Each rifle will have a bore snake pulled through the bore ONCE before the start of the test.
- Each rifle will fire 2 fouler shots after the bore snake cleaning and before firing the groups
for record
- Groups are fired with a Caldwell sand bag up front and a sand sock under the rear of the rifle
- Groups are fired slow fire at what ever pace the shooter desires.
- Groups are fired with a scope set on 16x (read about the rifles to see what makes & models are
currently being used)
- All rounds are fired through a chronograph to measure average velocity, standard deviation, and
extreme spread.
- Outside temperature is recorded for each series of tests as well as wind conditions
- Retesting is allowed but the entire test must be fired as a whole for that ammo
As you can see, there are not a lot of rounds fired for each make of ammo, but I needed to keep it
reasonable and I do reserve the right to do a retest. Shooter error certainly comes into play and the
results have both the raw averages as well as averages with the "called flyer" groups excluded. A
called flyer has to be called before looking at the target again.
There is no doubt that the test has flaws, but I have done my best to limit them as best as I could
and still provide some useful data. This is why I included the chronograph results as this provides
some true empirical data to examine, and not just some accuracy comparisons shot by a single shooter.
I have provided all the procedrues so you can take the test results for what they are worth!
The Test Rifles
For the tests, I wanted to have two rifles represented, a standard factory produced tactical rifle and
a high end custom tactical rifle. I also needed to know that I would have these rifles for a long time
to come so I could add more ammo as time goes by and still be able to do the same tests with the same
rifles. The two rifles I settled on was our Remington 700 mule rifle which is a
700 SPS-V in 308 with
a 26" barrel set into a remington 700P HS Precision stock. The SPS-V barreled action is the same as the
700P, 700 VS, and other remington heavy barrel rifles. It still does retain the X-Mark pro trigger which
is set to 3 lbs. This rifle is essentially a 700P and represents a very popular and common tactical
rifle in use by many agencies and has typically fired about .75 MOA with Federal GMM.
The scope used currently is a Mueller 4-16x50mm Tac I. All groups were fired with the scope set on 16x.
Remington 700 Test rifle at the cleaning/fouler station
The second rifle used for the high end tests is a Tactical Operations Bravo-51
with a 22" barrel. This rifle will shoot sub .25 MOA with federal gold medal match ammo if the shooter
does his part. It is a very high end rifle with very high accuracy requirements before leaving the factory.
The rifle is also threaded for a suppressor and all groups were indeed fired with a Tactical Operations
suppressor attached to the rifle. The rifle is pretty much setup as it came from the factory except for
the tests I have replaced my normal scope (Leupold Mark 4 10x M3) with a Leupold Mark 4 16x M1 in order
to meet the criteria of 16x for group firing.
Bravo-51 at the group firing station
These rifles should serve as a good sample of what might be expected with this ammo performing in various
rifles. Tac-Ops guarantees their rifles using the Federal GMM ammo, but I am not aware of anything
special they do specifically for that ammo. Beyond that, these rifles will be in our inventory for a long
time to come and we might as well get going with the test results!
Test Results
l-r: Lapua, Hornady, ABT, HSM, Blackhills, Winchester, Remington, Federal
The initial test included 8 manufacturers of match grade ammunition including Lapua, Hornady,
American Ballistics Technology (ABT), Hunting Shack Munitions (HSM), Blackhills, Winchester,
Remington and Federal. There will be more added over time as we continue to test more match grade
ammunition. The summary of the results is included in the table below, but be sure to visit each
manufacturers result page to find out more specific details on how the ammo performed as well
as photos of the ammo, best groups fired, price, etc.
Conclusion and Thoughts
So, after all of this shooting and note taking, what conclusions can be drawn? As most all shooters know,
rifles will favor a particular load for what ever reason, and I do not think I have proven otherwise
with these tests. I would also venture to say that the single biggest limiting factor of modern factory
match ammunition is the person behind the rifle. While I tried to take out as much human factor as I
could, the rifle was still not in a clamped down vise with a mechanical device pulling the trigger,
and therefore the groups were subject to the shooter and his errors. Which as we well know can be
effected by many many things. I do plan to re-fire some of the above manufacturers to see if better
results can be achieved, and we'll see how those go.
There are a few things of note that I would like to mention. It does appear that a nice tight chamber
and a high quality barrel on a custom built rifle does effect things, as you will notice that the
standard deviation and extreme spreads were reduced with the Bravo-51 on all but two of the loads
and on the average of all the loads together. On some of them, it was very significant. The 700P
actually has fewer rounds
through it than the Bravo-51, so we cannot put blame on throat wear or anything like that. Though this
discovery really isn't that surprising, BUT, perhaps the average velocities are. The 700P has a 26"
barrel and the Bravo has a 22" barrel (23" if you measure it the same as Remington does) but the
velocities were HIGHER in the Bravo-51 with the shorter barrel, which is contrary to accepted
theories. I believe there are a few reasons as to why this is the case.
The Bravo-51 has a custom barrel made for me with only three lands and grooves which puts a bit less drag on the
bullet as it travels down the barrel vs. a five or six land and groove barrel. I have no real
empirical evidence that I can offer to support a claim that this will actually increase velocities,
but, in theory it should. The second potential reason why we have extra velocity is because of
the tighter match grade type chamber which should seal tighter with less energy being used to
expand the brass vs. sending the bullet down the barrel. And my final idea as to why the velocities
may be higher with the shorter barrel is because these .308 match loadings are fairly low power and
we may actually be getting close to the maximum barrel length at which the .308 reaches it max
velocity. I have read that this usually happens around 30" for the .308, but I think that is for
higher velocity full power loads like the 155gr palma loads (palma rifles have long barrels). If you
look at the results of the Lapua loading, it is a very hot load, the fastest of this group by far, and
you will notice that in the longer 26" barrel it outpaced the shorter Bravo-51 barrel by 30 fps. The
hotter loads utilize the longer barrels to generate the higher velocities, but the lower power loads
seem to possibly be reaching their max velocity around the 24" barrel length. Of course, all of the
above are non scientific theories of my own as to why the average velocities in the shorter barreled
Bravo-51 were higher than the longer barreled 700P.
So which ammo is the best? Well, that will have to be left up to you to decide. I think they are all
acceptable to use and it is pretty remarkable that the overall average accuracy for the off the shelf
700P was under .9". Factory mass produced rifle with factory mass produced ammo from eight major
manufacturers. There is enough verity with the ammo to allow you to evaluate and see which might
fit best for you and your situation. With this initial test, the HSM is the most accurate out of
these two rifles, but also has the lowest
muzzle velocity. If you are looking for extra long range punch, the Lapua load is probably the way
to go, as the velocities are higher than the rest by enough of a margin to really make a difference
in long range shooting applications.
And of course, every rifle likes a certain load; these loads give you the opportunity to try out
many different good loads to find the best for your rifle. If you are a department deciding a primary
load, then rifle preference is probably not as much of an issue. Hopefully this test provide some
useful information as to where to possibly start with your own testing. We'll do our part to continue
to offer updates and to further test new loads.
If you would like to request a particular match grade ammo be tested and posted, or if you are a
manufacturer and would like to request your ammo be tested, please feel free to
email me.
All spread out, hard at work.
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