Chrono Question

[RugerFan]

When shooting at targets I shoot at a VERY leisurely pace so the barrel doesn’t heat up (so as not to degrade accuracy). But when shooting a rifle through my new Chrony, I shoot fairly quickly thinking it wouldn’t matter. However, it seems that velocity will commonly decrease through the shot string. Will a rising barrel temp cause velocities to drop???

[Bass Ackward]

When shooting at targets I shoot at a VERY leisurely pace so the barrel doesn’t heat up (so as not to degrade accuracy). But when shooting a rifle through my new Chrony, I shoot fairly quickly thinking it wouldn’t matter. However, it seems that velocity will commonly decrease through the shot string. Will a rising barrel temp cause velocities to drop???

RF,

Surprised?

I've seen it go both ways from the same barrel depending on what conditions you were creating.

But that shouldn't be a shock considering that we have heard that strange things happen when barrels heat up whether using copper or lead. Whole philosophies about everything from bedding to fouling have sprung up over the years to deal with it. Light barrels heavy barrels, fluting, ventilated stocks, barrel bands, and the list goes on and on.

So now if you reproduce the same firing rate on a target, you will get to see what that velocity change translates too.

[RugerFan]

Not suprised, just curious what others have experienced. I guess I'll let my barrel cool somewhat between shots and see what happens.

[piwo]

I saw some footage shot in Viet Nam where the a-gunner in an M60 team was pouring water over the barrel to cool it down (they where shooting in a rice paddy and shallow water everywhere. You could see the bullets impacting out in front of the barrel not all that far from the muzzle prior to the A-gunner pouring the water over the barrel. These guys were up to their @#&^% in a fight, caught out in the open and the gunner never stopped blazing away.

I've heard of this before but didn't/don't know if it's really true, but if that film footage was showing and describing accurately, then I'd say it's certainly possible if not probable.

Things are not always as they seem however, and lacking the knowledge of metals under heat, don't really know. Just wanted to share this example I saw on film, at the extreme.

[DeanoBeanCounter]

I'm not surprised. One day I was shooting my very old Marlin 30-30, the bullets kept climbing on the target. A guy at work said it was probably because the barrel was cooked. Well I figured I'll adjust the sights for a cool barrel because there isn't any chance of getting a hot barrel hunting. The next time I went shooting I couldn't get it to climb on the target however hot I got the barrel. All I can say is conditions change. By the way that 100 year old Marlin is the most accurate gun I've got. It shoots better than the brand new Henry .22 rim fire I have. In a fire fight, I wouldn't quit shooting ether. I have been told that the general rule of thumb is don't get your barrel to hot to touch. True or not it sounds like a good idea.
Deano