Has anyone air gaged the chamber and muzzle of their Impact? I don't have the tools to do so, wondering if anyone has?
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Air Gauge FX Impact
- Thread starter ua5qb
- Start date
Do you mean measuring the air pressure inside the barrel? Have never heard of anyone doing that.
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I've been gauging pellets for consistency.
It started me thinking about what size is the liner's Internal Diameter, how deep is the rifling.
Copper projectiles can vary across the same designation, eg. .303 can be .312 or sometimes .311. You can buy different barrel twist rates for a caliber depending on the projectile used. Heavier projectiles faster twist rates. From this you can work out what projectile weight to buy. As an example a factory .222 calibre barrel for 55gr projectile would normally be around 1:12 twist. If you want to shoot 69gr projectile you need a 1:10 or 1:8 twist barrel.
Unfortunately this information is lacking, or I can't find it, from manufacturers. I took out the liner on my FX Impact tracing one of the grooves to determine it has 1:20 twist. Which seems insufficient to shoot .22 H&N Rabbit Magnum II, which I have lots of from previous air rifle.
Back to my original request, if the exact ID of the barrel is stated I could better match the pellets I gauge to fit the barrel on my FX Impact or decide which liner to buy.
It started me thinking about what size is the liner's Internal Diameter, how deep is the rifling.
Copper projectiles can vary across the same designation, eg. .303 can be .312 or sometimes .311. You can buy different barrel twist rates for a caliber depending on the projectile used. Heavier projectiles faster twist rates. From this you can work out what projectile weight to buy. As an example a factory .222 calibre barrel for 55gr projectile would normally be around 1:12 twist. If you want to shoot 69gr projectile you need a 1:10 or 1:8 twist barrel.
Unfortunately this information is lacking, or I can't find it, from manufacturers. I took out the liner on my FX Impact tracing one of the grooves to determine it has 1:20 twist. Which seems insufficient to shoot .22 H&N Rabbit Magnum II, which I have lots of from previous air rifle.
Back to my original request, if the exact ID of the barrel is stated I could better match the pellets I gauge to fit the barrel on my FX Impact or decide which liner to buy.
Upvote 0