What Headspace Does ELEY Ammunition Need?
ELEY publishes a recommended headspace of 0.040-0.041 in for its .22LR ammunition. That figure applies across the range: ELEY tenex, ELEY match, ELEY team, ELEY club, ELEY sport and the rest are all built to a common 25.4 mm / 1 inch cartridge length and the same published dimensional standard.
It is one of only two rifle-side numbers ELEY publishes, the other being a strike depth of 0.012-0.015 in. Together they define the mechanical conditions in which an ELEY cartridge is designed to ignite, chamber and extract reliably.
What Headspace Means in a Rimfire Rifle
In a centrefire rifle, headspace is usually measured to a shoulder or a case datum. In a rimfire, the cartridge locates on its rim. The rim sits in a recess cut into the rear face of the barrel, and headspace is the clearance that governs how that rim is held between the barrel and the bolt face.
Get it right and the cartridge is held square and firmly, in the same position, every time the bolt closes. That repeatability is the whole point: ignition energy, bullet alignment with the bore and extraction all depend on the cartridge starting from a consistent position.
Why Headspace Matters for Ignition
A rimfire round fires because the firing pin crushes the rim against the edge of the chamber, detonating the priming compound folded inside it. That only works if the rim is supported.
If the rim is not held firmly enough, part of the firing pin’s energy pushes the cartridge forward instead of crushing the rim, producing a shallower indent and less energy delivered into the priming compound. If the rim is held too tightly, the bolt becomes hard to close. The published 0.040-0.041 in window is the clearance in which the rim is supported firmly enough to be crushed properly, while still leaving the action free to close cleanly on every round.
Why Headspace Matters for Extraction
Headspace also governs how the fired case is presented to the extractor. Correct clearance means the case sits square in the chamber, expands predictably against the chamber wall on firing, and is picked up cleanly as the bolt is drawn back.
This is where lubrication earns its keep too. The purpose of the wax on a .22LR cartridge is to ease repeated chambering. The idea that lubricant sends the bullet down the barrel is a common misconception. ELEY applies lubricant through a temperature-controlled system to ensure consistent chambering and consistent barrel protection, and the beeswax-tallow used on ELEY tenex, ELEY match and ELEY team is deliberately softer, thicker and stickier in order to minimise the effects of chambering.
How Headspace Relates to Strike Depth
Headspace and strike depth are two measurements of the same mechanism, taken from opposite ends.
| Specification | Published ELEY figure | What it describes | How it is measured |
|---|---|---|---|
| Headspace | 0.040-0.041 in | Clearance holding the cartridge rim between barrel and bolt face | Headspace gauge |
| Strike depth | 0.012-0.015 in | The indent left by the firing pin, at which the primer is activated | Strike depth gauge |
Strike depth is the outcome; headspace is one of the conditions that produces it. A rifle with headspace outside the published window will usually show it in the strike depth reading, because the rim is not being supported where the firing pin was designed to strike it. This is why the practical check is to measure strike depth first: one inexpensive gauge tells you whether the whole system is delivering.
Both figures are worth re-checking over the life of a rifle rather than once at purchase: components bed in, firing pin springs weaken over thousands of rounds, and old lubricant thickens inside the bolt. Correcting headspace is gunsmith work, involving the barrel’s rim recess and the bolt rather than the ammunition.
The Bottom Line
ELEY’s recommended headspace is 0.040-0.041 in, and its ideal strike depth is 0.012-0.015 in. Headspace holds the cartridge rim in a repeatable position so the firing pin can crush it properly and the extractor can pick the case up cleanly; strike depth confirms that the energy actually arrived. Check both against ELEY’s published figures, and the firearm side of the Triangle of Success is verified.
With the rifle set to specification, the remaining variable is which production lot suits your barrel. Book a batch test at eley.co.uk/vip, or explore the proof data behind any batch free of charge at eleyxshot.com.