Release notes

2026-09-21, commit 85a4ac4. Nightly.

New

• Where you have not said what you were shooting, GroupLab now reads a likely calibre from the holes and asks you to confirm it before accepting, because knowing it finds holes that would otherwise be refused.

Downloads for this build

2026-09-21, commit 3c6db96. Nightly.

Nothing in this build changes what you see or do. It carries internal work only.

Downloads for this build

2026-09-21, commit dd57b31. Nightly.

New

• GroupLab now reads the likely calibre from your holes and asks you to confirm or correct it, because knowing it lets GroupLab find holes it would otherwise refuse.

Changed

• The shot distance now has its own yards or metres choice beside it, so you can type it in the unit you think in without changing a setting.

Downloads for this build

2026-09-21, commit 37686b9. Nightly.

New

• Every figure on the analysis page now has a ? beside it explaining what it means and what the number of shots does to it.
• The analysis page can now be switched between inches with MOA and centimetres with mil, and remembers which you chose. Your saved sessions are unchanged either way.
• The analysis page can now show your group's mean radius per 100 yards on a scale, against rules of thumb quoted on a Hornady podcast, with a plain note on how much weight your shot count can carry.
• The zero correction is now shown in MOA, mil, inches and centimetres at once, with the number of clicks to turn where your rifle's scope details are recorded.
• Every edit now shows a short line at the bottom right saying what changed, with an Undo button beside it, instead of changing the sheet silently.

Fixed

• Rifles and loads now keep everything you type about them. Sight height, zero distance, muzzle velocity, ballistic coefficient and the rest were being lost when the records were saved.

Changed

• The guides now cover updates, the shot editor, the explanations beside each figure and why naming your calibre matters.
• The download is about a third smaller, and the installed application about 128 MB smaller, with no change to what it does.

Known issues

• This build's notes said GroupLab "now works out where your group actually landed before deciding which bull each shot belongs to". That was not true of this build: the working part was there and nothing on any screen could reach it. Corrected from nightly 30 onwards.

Downloads for this build

2026-09-21, commit e5887a8. Nightly.

The first build whose notes were written for a person rather than taken from commit subjects. It opens with a plain summary of everything since nightly 18, because those builds went out with notes that said nothing.

Fixed

• When GroupLab finds fewer holes than the shots you fired, it now says so and names the bulls with nothing on them, instead of showing a clean result you have no reason to question.
• Holes from small calibres such as .22 LR are no longer refused as too small when you have entered the calibre.
• A hole cut off by the edge of the scan is detected instead of being ignored.
• A shot that landed off the bulls is kept and offered, instead of being dropped.

Changed

• Where the shot to bull assignment is not certain, the group figures say so, and the zero correction is withheld rather than being given from shots that may belong elsewhere.
• A blank sheet scanned on a flatbed can use the scan's own resolution as its scale. GroupLab shows the number and you can refuse it.
• The Support button opens the support page at grouplab.org, and the report window tells you both ways to send a report.

Downloads for this build

2026-09-21, commit b089122. Nightly.

The build used to prove the updater end to end: nightly 25 updated itself to this one on a real machine, with real clicks, in under two minutes and with no installer window and no administrator prompt.

Known issues

• The notes on the release itself are commit subjects and say nothing useful. Fixed from nightly 27.

Downloads for this build

2026-09-21, commit 03c5821. Nightly.

Fixed

• GroupLab can update itself at last. Every build before this one refused its own update as unsigned, whichever version it was, so it could never install anything.

If you are on nightly 18 or earlier you have to install this one, or a later one, by hand, once. After that it updates itself.

Known issues

• The notes on the release itself are commit subjects and say nothing useful. Fixed from nightly 27.

Downloads for this build

2026-09-21, commit a5e90de. Nightly.

Known issues

• Cannot update itself. It refuses its own update as unsigned. Install a later build by hand once.
• The notes on the release itself are commit subjects and say nothing useful.

Downloads for this build

2026-09-21, commit b39b7af. Nightly.

Fixed

• The build no longer describes itself as a development build in Settings, and looks for updates.

Known issues

• Cannot update itself. It refuses its own update as unsigned. Install a later build by hand once.

Downloads for this build

2026-09-21, commit 9db6500. Nightly.

Known issues

• Calls itself a development build in Settings, and never looks for an update.
• Cannot update itself.

Downloads for this build

2026-09-21, commit 862aab2. Nightly. The first automatic nightly.

Known issues

• Calls itself a development build in Settings, and never looks for an update.
• Cannot update itself.

Downloads for this build

2026-09-21, commit 5a4cd07. The first build anyone could download.

New

• The Windows installer and zip, and the Linux tarball. Each carries its own .NET runtime, so nothing else has to be installed.

Known issues

• Published as a release by mistake. GroupLab is unreleased, and this is marked a pre-release now.
• Cannot update itself. Install a nightly by hand.

This build is deliberately not linked for download. It was published as a release when it should not have been, it cannot update itself, and sending anybody to it now would be sending them to the one build that is a dead end. It is listed here because it happened, not because it is worth installing.