What Extreme Spread and Standard Deviation Should I Expect From ELEY match?

ELEY’s aim for ELEY match is a single-digit extreme spread, alongside its published accuracy standard of 4.74 mm Radial Standard Deviation (RSD). That is the target ELEY manufactures to, and it is the honest answer to what you should expect.

Beyond that, ELEY grades and publishes its ammunition on RSD rather than on extreme spread. The 4.74 mm RSD figure for ELEY match is verified by firing 200 rounds from every batch across four different firearm brands. ELEY does not publish a specific extreme spread or standard deviation number as part of the product specification, so no figure beyond “single digits” should be inferred or quoted.

What ELEY does publish for velocity is more useful than a single summary statistic: the mean velocity of your specific batch is printed on your box, and batch-level velocity data is free to access through the Lot Analyser at eleyxshot.com, which now carries all lots for ELEY tenex, ELEY tenex pistol, ELEY tenex biathlon, ELEY tenex rapid fire pistol, ELEY match, ELEY semi-auto .22LR benchrest precision, ELEY ultra and ELEY club.

Why RSD Rather Than Extreme Spread

The difference between the two statistics is not a matter of preference. It is a matter of how much of the data each one uses.

Extreme spread considers only the two furthest shots. Whether applied to group size or to velocity, it discards everything in between, and a single outlier defines the entire result. Two batches with genuinely different performance can return the same extreme spread, and the same batch measured twice can return very different figures depending on whether an outlier happened to appear.

RSD evaluates every shot fired. It measures the distance from each shot hole to the group’s centre point, the mean point of impact. The lower the RSD, the closer the group and the more consistent the performance.

For judging whether a batch will hold together across a full course of fire rather than one fortunate target, the statistic that uses all the data is the one that answers the question. That is why ELEY manufactures to a single-digit extreme spread as an internal goal but grades and publishes on RSD: the goal keeps the outliers in check, the published standard describes the whole group.

The Published Accuracy Standards

These are maxima that every batch has already demonstrated it can meet in proof testing, not typical or best-case results.

What Drives Velocity Consistency in an ELEY Cartridge

Shooters who ask about extreme spread and standard deviation are usually asking a more fundamental question: how consistently does this ammunition burn? That is a manufacturing question.

• Propellant is measured electronically for each individual cartridge, not dispensed volumetrically for a batch.
• Priming takes place in an advanced air-conditioned facility delivering a 75% improvement in the spread of primer weights compared to other manufacturers.
• Case mouths are trimmed flat and crimped to exacting standards for optimum round-to-round bullet pull-out force. ELEY match specifically uses a cut mouth case, delivering consistent internal ballistics performance.
• Six Sigma methodologies and high-speed electronic visual inspection run through the process, with high-tech inspection of the critical heel area.

Getting Velocity Data for Your Batch

Two published sources give you real numbers rather than estimates.

The box. Every ELEY box carries a batch code ending in the mean velocity for that batch, measured across four barrels during proofing. In a code reading 10 26-04 244 over 1045, the 1045 is that mean.

The Lot Analyser at eleyxshot.com. Create a free account, enter your batch number, and you can access ELEY’s proof data for that batch: the complete 200-shot proof group with X and Y coordinates for every shot, plus velocity, group size, shot distribution, date loaded, ballistic coefficient, trajectory and radial dispersion across four barrel types. All lots are now carried for ELEY tenex, ELEY tenex pistol, ELEY tenex biathlon, ELEY tenex rapid fire pistol, ELEY match, ELEY semi-auto .22LR benchrest precision, ELEY ultra and ELEY club, which means every ELEY match lot is there. If you want to characterise the velocity behaviour of a batch before committing to it, that is the data set to work from.

ELEY ammunition is supplied in 50-round boxes, 500-round bricks and 5,000-round outer cases, so a brick gives you enough of a single lot to characterise it properly and then shoot it. Stockists are listed at eley.co.uk/retailers.

Measuring It Yourself

Nothing prevents you from calculating extreme spread and standard deviation from your own chronograph data, and for solver truing you should. Two points are worth holding onto. Your figures describe your barrel and your conditions on the day, not the ammunition in isolation: barrel length, bore dimensions, chamber and throat condition and ambient temperature all move measured velocity. And a velocity statistic, however carefully derived, does not by itself predict group size. That is why the practical route to performance is batch testing: evaluating up to 20 batches through your own barrel at eley.co.uk/vip until you find the lot your rifle shoots best.

The Bottom Line

ELEY’s goal for ELEY match is a single-digit extreme spread, and its published accuracy standard is a maximum of 4.74 mm RSD, verified across 200 rounds from every batch through four different firearm brands. RSD is the figure ELEY publishes because it uses every shot fired, while extreme spread uses only the two furthest. No numeric ES or SD figure is published beyond that single-digit goal, so treat any specific number you see quoted with caution.

For velocity data, read the four-barrel mean printed on your box and the batch-level figures in the free Lot Analyser at eleyxshot.com. Then confirm it on the target through batch testing in your own rifle.