Against the grain
Sporting Gun|May 2023
Bruce Potts highlights problems he has identified when converting from lead to non-lead bullets in a rimfire and outlines his concerns about this
Bruce Potts
Against the grain

Lead-free ammunition for centrefire rounds is becoming far more prevalent. But what of the .22 rimfire? To convert a conventional lead .22 calibre bullet to lead-free involves a substitution to the tin or zinc mixture.

This is counter-intuitive, as it means that for a bullet to be the same dimensions – which is the length needed to stabilise in a traditional one-in-16in rifling twist rate – it means that the weight is nearly half that of the original lead .22 rimfire projectile if it’s non-lead. That’s why the only available .22LR lead-free ammunition have bullet weights from 24 to 26 grains (gr).

This brings up another issue. The velocities for such light projectiles increase past 1,500 feet per second (fps), making them hyper-velocity bullets well above the speed of sound. This negates its use as a quiet pest control round with a sound moderator, and has a detrimental effect on ballistics for both consistent velocities, accuracy and downrange energy retention.

Another problem that affects accuracy is lubrication down the bore. This affects fouling and fouling build-up in the rifling grooves of the chamber area, and is worsened by non-lead alternatives. You have to condition the bore when you switch ammunition types. It’s like when you clean a rimfire’s bore – you have to shoot it back in to condition the bore to that type of ammo to achieve best accuracy.

That said, it is pretty much inevitable that lead-free rimfire ammunition is on the cards, and I have three brands to look at to see how they shoot – RWS, Norma and Winchester.

RWS and Norma 

Denne historien er fra May 2023-utgaven av Sporting Gun.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

Denne historien er fra May 2023-utgaven av Sporting Gun.

Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.

FLERE HISTORIER FRA SPORTING GUNSe alt
Thermal spectrum
Sporting Gun

Thermal spectrum

Paul Austin explores both ends of the thermal market with latest high-end release from Zeiss alongside a surprising entry-level offering from Xinfrared

time-read
6 mins  |
August 2023
Roe, rucks and new ground
Sporting Gun

Roe, rucks and new ground

Jon Snowdon and his team have much to keep them busy and a new tool to help them

time-read
4 mins  |
August 2023
Tales from a lifetime of foxing
Sporting Gun

Tales from a lifetime of foxing

Join Mike Powell as he explores the evolving world of fox shooting, drawing from a career that spans seven decades

time-read
3 mins  |
August 2023
Fox rot about Charlie
Sporting Gun

Fox rot about Charlie

Patrick Hook responds to claims that fox numbers are dangerously on the wane

time-read
3 mins  |
August 2023
The sniff of success
Sporting Gun

The sniff of success

Join Ryan Kay as he navigates the fascinating dynamic between a handler and their canine companion

time-read
3 mins  |
August 2023
Adventures of Nick & Ted
Sporting Gun

Adventures of Nick & Ted

A new chapter in the histories of Sporting Gun and Sporting Shooter has Nick Ridley reflecting on the dogs he has trained over the years he has been associated with the magazines

time-read
3 mins  |
August 2023
The problem: Inflammation in the nervous system
Sporting Gun

The problem: Inflammation in the nervous system

Vet's advice

time-read
3 mins  |
August 2023
Gundogs Q&A
Sporting Gun

Gundogs Q&A

No problem goes unsolved as Sporting Gun puts your questions to the gundog experts

time-read
4 mins  |
August 2023
Stop-start!
Sporting Gun

Stop-start!

Fran Ardley continues her training tips on disciplining your dog to the stop whistle and the exercises you need to do

time-read
3 mins  |
August 2023
Gundogs at the Game Fair
Sporting Gun

Gundogs at the Game Fair

Organising the Game Fair's prestigious gundog competitions: behind-the-scenes with Francesca Prentice

time-read
2 mins  |
August 2023