The Daystate Guide To Airgun Barrels – Part Three

This is the final part of a series of three posts about airgun barrels by Daystate’s Tony Belas.

Here Tony discussed barrel care and the better barrel. Take it away, Tony…

Fair Wear And Tear

Everything wears out, and the extreme dry-running environment of the barrel is no exception. Barrel life can vary from a few thousand rounds for a high caliber pistol to hundreds of thousands for an air rifle.

But once rust has got a hold on a barrel that’s it, and the only real option is to replace it.
All barrel life can be extended using a good cleaning regime (or shortened with a bad one) and the use of bullet/pellet lubes where appropriate.

Below, much of Tony’s information applies to firearms ammo as well as airgun pellets.

A quick note for air gunners. While the liberal use of a fine oil as a pellet lube is a good idea on a PCP, on a spring gun the lubricant needs to be inert and waxed based. Due to the high pressures involved in piston airguns, oil may ignite. If it does, it can wreck the accuracy, and/or the mainspring.

Tradition has barrels being pulled through with a piece of “cleaning flannelette” and a wire brush. But with the vast array of super-efficient chemical solvents made these days, I feel it’s a good idea to avoid anything abrasive unless things have been left too long.

While we are on the subject, the size of patch used to pull through the barrel is quite important. It is a good idea to start with a patch too small and work your way up to a firm, but not tight, fit.

I say this but I might also add that I have never met anyone who has been around airguns or firearms for any length of time that hasn’t got something stuck up a barrel!

A Better Barrel

Pushing a soft lead plug or pellet through the bore and examining the rifling marks can help identify any rough spots or damage to the rifling perhaps caused by careless cleaning.

It can also indicate any bulges or loose points. Surprisingly enough, this doesn’t always affect the accuracy, unless quite bad or uneven.

Polishing the inside of the rifle bore can, on occasions improve a barrel, but proceed with care. The aim is not to add wear, lands are better clean and sharp, and a wrong polishing regime can easily do more harm than good.

The traditional method used by gunsmiths in the know is ‘lapping”. Here, a two-Inch length is cut off the barrel blank to form a mould in which a piece of welding rod is inserted.

Molten lead is then poured in and when removed from the mould the lead has the exact profile of the rifling on it. The resulting “jag” is used with jeweler’s rouge to polish the inside of the barrel until the jag wears out. A new jag is then made, and the process continues.

Fire Lapping

A less complicated method which can be used by owners of PCP air rifles is to coat a hundred or so pellets with a mixture of jeweler’s rouge and oil, and shoot the barrel smooth.

The mixture is expelled as a sticky mess, so first remove any silencer or muzzle break!

Barrel Twist Rates At Daystate

At Daystate and BRK, we use multiple different twist rates and land profiles, even variations to the choke taper. All is decided-on based on what produces the best accuracy in each combination of energy/pellet/slug/caliber.

What’s more is that changes over time! For example, the barrel fitted today to a 2024 Delta Wolf has a different profile to one from 2020.

Below. Lothar Walther barrels ready for installation into air rifles at the Daystate factory.

Daystate Guide To Airgun Barrels

So here’s my standard answer to the question: “What’s the twist rate of a Daystate barrel?”

Firstly, it’s unlikely that any twist rate you can put in will affect the prediction on the program for fall of shot on an air rifle that only shoots out to 100 Yards.

With firearms shooting up to 1,000 Yards spindrift, even the “Coriolis effect” has to be factored-in.

As far as I know, all ballistics programs are written primarily for firearms and bullets rather than airguns firing pellets. So they usually insist on a twist rate value being entered.

The figure that we advise is 1:18 right hand twist. But with Strelock, if you try 1:18 and then change to 1:30 twist rate, you will notice no difference to the program’s prediction within normal airgun ranges: that is out to 100 Yards.

So – in my opinion – the twist rate for airgun barrels is much less significant an issue than many other aspects of the gun and – even more so – the ability of the shooter.

Daystate Guide To Airgun Barrels

Thanks, Tony, for a very interesting and thought-provoking series! You can find Part One here. Part Two is here.