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Some time back several members took up an offer to obtain a copy of the excellent free internal ballistic calculator of this name. That version no longer works, having been superseded by the current version, which looks essentially the same, but with some changes and updates. It is supported by a user group which you can join.

It took an hour using fast broadband to download the archive, which then needed to be unpacked and installed. If any members would like a copy of the current version (Windows & Linux only), please contact the club. We can then distribute copies at a monthly meeting.

For those unfamiliar with this software, it very accurately predicts pressures and expected velocities. Virtually every available projectile, powder and cartridge is listed, with the exception of some less popular ADI powders. ADI does have information on equivalent powders in other brands which I have used…

At last a series of relatively short instructional videos on accurate shooting; actually F Class shooting, but applicable to everyone wanting to make accurate ammunition. This guy is scientific, knows how to test ideas and get valid results. I'll be interested in your opinion. He explodes many myths about what's important, what is worth doing and what is not. Having chased accuracy nodes in various ways over the years, his video on that subject explains a lot from my personal experience.

Regarding my article on sorting rimfire ammunition in the "How To" section of this website, rather than re-writing that article to include some actual figures, I will publish them here, and will add to them as time goes on. This blog is the closest we have to include rimfire.

Groups shot at St Marys indoor range at 50m using an Anchutz 64 GPR rifle and 24 X BR scope. These figures are averages of several 5 shot groups in each case.

These are from my early days of sorting, with ammunition which may no longer be current. However they illustrate the point that significant reductions in group sizes can be obtained just by sorting. In group or score BR events, sorting can easily make the difference between running first or last.

Eley Subsonic HP; sorted rounds by weight and rim thickness 0.560" +/- 0.157" (variation between smallest and largest groups).

The website has been growing steadily with new information now available like the Range open or closed links to either the RFS website or to Sport and Rec’s advisory site. The articles are growing more so to. So a big thanks to Cam and Dal, for being the main contributors to our advancements.

Just like to take this opportunity to wish all the members and their families. The very best of season greetings and a happy new year. I hope you all have an enjoyable and safe time if you are travelling or a relaxing time at home with family. Look forward to catching up again on the range or at our secluded meetings next year.

Since publishing on this site in my article on three methods to find most accurate loads, the opinion that less expensive chronographs probably would not be able to find speed nodes I have found that my cheap old "Chrony" is quite capable of doing so. The results of three series of 222 Rem. load tests each using different components mirrored the published results from the Labradar chronograph. The ladder tests shot simultaneously matched up with the speed nodes nicely. For this rifle at least, (a light barrelled Sako Vixen) the higher speed nodes produced very tight groups of 0.2 moa and under at 200m.

It’s good to have you here! Feel free to share anything - stories, ideas, pictures or whatever is on your mind. Here you can start discussions, connect with members, reply to comments, and more.

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