TESTING AMMUNITION

TESTING AMMUNITION.

In June 2011, Robyn Ridley, Warren Potent and Dane Sampson visited the Eley factory in the UK, with the aim of testing their (and other) barrels to determine the best batch of ammunition to use over the coming year.

Obviously, the data on these pages will not specifically help other shooters, as each barrel has a particular batch that works best in that barrel. It does show quite a range in a particular barrel—which batches work well, and those that really don’t.

So– what is involved in testing at Eley? For starters, a lot of time! Each person must do the hard yards, and just put bullet after bullet into their barrel, letting the computer record group size and placement.

How it the rifle barrel secured. As you can see, it is a reliable clamping system to hold the barrel.

After an initial round of testing, the “best batches” are noted, and another round of testing is under way. From this next round of testing, more attention is paid to those batches that appear to work.

However, that is not the end of the story.

More testing, and higher scrutiny of group size and shape. It is not purely about the group size, as seen here at right. The group sizes at 17.1 and 17.2—very close, however the shape of the group differs greatly.

Remembering that each barrel has its own special requirements, and noting that all the groups in this article were from the same barrel, so as to not confuse the issue, one needs to also look at the range of the group sizes, From 15.8–20.3

Which batch would you discard first? Also note the shape of the 19.5 group—quite fair at first glance, but three or four shots are definitely well out of the group….that one’s out as well. The ammunition was not tested in the field, and it is common for some variances to occur once outside the closed testing range (often better!)

However, common sense would suggest that an ammunition that is shooting very tight groups in the test situation, will probably shoot well on any range, given that the shooter is competent.

The shooter whose groups I have illustrated above, obviously decided to go with the batch that produced the groups…consistent and small……

If the barrel will shoot groups like this with this ammunition, then there is more chance that the group sizes will remain close to the factory, when shot out of the shoulder and on the open range.

I firmly believe that everyone can, and should take the time to test the ammunition that they have purchased.  While we do not often have the option of selecting batches, we can at the very least, know the potential capabilities of the ammunition in the barrel.

Now to hear from one of the shooters – Robyn….

Warren, Dane and I arrived bright and early in London and then had a rather cold and rainy (typical England) drive up to Birmingham where the Eley factory is located. We were there for two days to test our barrels. Each barrel takes about 2 hours (if you’re quick) and the factory can test two at a time.

For testing, there were 23 batches of Tenex available to us. It is also useful to bring along to Eley, 50 rounds of a batch currently being used, as a ‘test’ group. This works by establishing a benchmark group first, and will also tell you whether you’ve found anything better than the batch you’re currently using.

This is not absolutely necessary, especially if you have not been using one consistent batch, however it is useful. If you’ve been shooting scores you like with a batch you’ve been using, and then find a better batch, it gives you a great deal of confidence that the ammo will be giving the best possible on match day.

We all started by shooting 10 shot groups with these 23 batches, then eliminated all those batches that did not group well, eg had shots out of the group etc and choose the best groups to keep testing. In my case I has 11 batches that I wanted to test again.

With those batches you want to test again, you go on to shoot another 30 shots to form 40 shot groups to compare against each other. To compare, you get a print out of how all the batches tested in your barrel, including the initial 10 shot group and the 40 shot group size, total score and a breakdown of how may of each score (10.9, 10.8, 10.7 etc) are in the group.

After comparing, I decided that there were 4 batches that worked quite well in my barrel, The trick was then deciding which one was the best! I

In the end I decided on a group that was fairly round, a high score and one that did not have much less than a 10.3. Just choosing the smallest group may not always be the best, as groups will generally get tighter shooting out of the shoulder anyway, so you also have to consider the shape of the group (shots left and right to far out are a definite no-no, high and low shots, within reason, can usually be accounted for due to the clamp and can disappear back into the group when shooting from the shoulder) and score you would achieve using that batch of ammunition.

It is important to note how different all the barrels we tested were, and that just because one batch tested well in one barrel, certainly didn’t mean it would test well in another.

Luckily for us, all our barrels tested very differently and we didn’t have to argue over who would get the ammunition from a particular batch. Especially lucky for Warren and Dane that their barrels didn’t test the same as mine, as I decided to take all remaining stock of the batch I particularly like, and chose.

The two days of testing at Eley were a good experience and it did reinforce how much I like my Anschutz barrel, as it has always been fairly consistent with testing, and again I found a number of batches that worked quite well.

After watching 6 other barrels being tested, I know that a non fussy rifle barrel is quite a blessing!

Although all this happened many thousands of kilometers away, the process can be replicated at home here in Australia. Sydney and Adelaide ranges both have reliable clamps that can be used for testing.

There may not be quite as many batches to choose from in Australia, yet finding the ‘best of the bunch’ for your rifle is an important part of improving scores and going into a match with far greater confidence.

Enjoy the challenge
Tricia

 

 

 

Tags: AMMO, TESTING