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crabo
01-04-2009, 12:02 AM
When shooting rifle groups, between shots? I know different barrels heat up and cool down faster while being shot. How do you decide when enough time has passed before the next shot?

I have seen some articles where people use fans and water, but if it is a warm 83 degree Texas day, what is a good guideline?

Thanks,

docone31
01-04-2009, 12:18 AM
If you can kiss the barrel, you can shoot it.
Long life that way.

armoredman
01-04-2009, 02:37 AM
For my bolt actions, I shoot three round groups usually, and that's fire, work the bolt, sight, fire, etc. Afterwards the barrel cools while I check the group.

bushka
01-04-2009, 03:06 AM
well,in a sauer 202 in 300 winmag,3 shots in a minute and half produced 1.5"
@100yds scoped/ benched.
so,you are safe within those limits unless you burn more than say 60 grains of powder a pop.

eka
01-04-2009, 10:36 AM
For my light cast boolit loads using pistol powders I usually shoot five and then give it a cool down time. I haven't noticed these load generating enough heat to make much of a difference. With the exception of those 100+ degree summer days. You know, the ones where you take your boolits to the range in a cooler to keep the lube from running off.

With higher pressure loads, I wait five minutes between shots and at least fifteen minutes between groups. Seems to work OK, but nothing scientific as to why I came up with that amount of time. Reducing throat wear is the main objective as well as hopefully allowing for smaller groups.

Keith

dromia
01-04-2009, 11:54 AM
For cast I'll shoot five shot groups and let it cool, unless it's one of those rare occassions when its blistering hot.

I just touch the barrel in front of the knox form and if its more than slightly warm I wait a bit.

montana_charlie
01-04-2009, 12:48 PM
I'd say it depends on what you are looking for...or trying to stay away from.

If you experience accuracy variations between hot and cold barrel states, you find yourself wondering if the ammunition performance changes at differing temperatures...or if a 'hot' barrel is 'walking' shots on around the paper.

I had a 30-06 bolt gun that had a walking barrel. As it warmed, the impact moved higher and to the left. It was so predictable, you could almost use it to correct for wind and range variations. Since it was a hunting piece, the walking barrel was not an issue. It only came into play when developing loads at the bench.

I haven't heated up my 45/90 (much) because I spend a minute or two dinking around with scoping, data recording, and blow tubing between shots.
I am confident the barrel won't start 'walking' because of the type of steel it's made from. If I ever DO get it hot...and groups change...I expect it will be due to the black powder burning differently in a 'hotter environment'.

One thing I have ALWAYS believed about barrel temperature is...
It needs to be the same on all sides of the barrel. If the rifle (even with a 'cold' barrel) is in the sunshine when not being fired, I will turn it occasionally in an effort to keep everything 'even'.

CM

Kraschenbirn
01-04-2009, 12:49 PM
During load development/testing for a bolt-action or single-shot, around 20-30 seconds with the action open between shots. Fire, eject/retrieve empty, check POI through spotting scope, check chrono reading (if I'm using one), remount rifle, close action, establish sight picture, repeat process.

Bill

Down South
01-04-2009, 10:12 PM
I shoot three to four shot groups depending on the rifle. I let the barrel cool back down to ambient temperature before the next group.

HangFireW8
01-04-2009, 10:21 PM
When shooting rifle groups, between shots? I know different barrels heat up and cool down faster while being shot. How do you decide when enough time has passed before the next shot?

I shoot as fast as I can reasonably aim. However, I switch rifles (and targets) between shots, unless it is the .22. I always take my .22 and at least two big rifles. If it is a hot day, I try to take 3 or 4 big rifles.

My rhythm depends on the outside temperature, my recoil tolerance, how fast stuff heats up. Usually it's something like this:

Big1
.22 5 times
Big2
.22 10 times
Big3
.22 5 times
(repeat)

As for recoil tolerance, the .22 is a great nerve settler, and I am currently in the process of replacing 5 factory recoil pads with Pachmayr Decelerators. (One down, four to go). I have already put risers on my iron bench rest, to raise the rifle so I am not leaning forward and bearing it on my collarbone. That means I will be able to shoot faster.

How fast a barrel heats up depends primarily on velocity and how overbore it is. The slowest heater would probably be a .45Colt carbine. The fastest would be something like a .220Swift light barrel shooting full-house loads.

I shoot old military rifles the fastest, because they were meant to take it. I shoot lightweight mountain rifles the slowest, not just for barrel heating, but because they are so light the recoil adds up on me.

Shooting the .22 at 50 yards standing is a great way to practice shooting, plus it allows me to leave a big rifle on the rest. It amuses me when my .22 groups better at 50 than the next guy's deer rifle... and I'm shooting iron sights.

-HF

montana_charlie
01-05-2009, 04:01 PM
Do you get a discount on range fees based on how much extra ammunition you can burn up?

Dan Cash
01-05-2009, 04:31 PM
One thing I have ALWAYS believed about barrel temperature is...
It needs to be the same on all sides of the barrel. If the rifle (even with a 'cold' barrel) is in the sunshine when not being fired, I will turn it occasionally in an effort to keep everything 'even'.

CM

You are so correct on this, Charlie. The barrel will bend away from the hot side and really move the POI. The first shot will usually even out the heat and normalize the barrel until the heat on one side increases again.

Heavy lead
01-05-2009, 04:36 PM
I try to work with at least 4 rifles at a time, I know when to go, so I usually have two benches to work with too. In between groups (usually groups of 3 or 5 are taken quite quickley, just as if hunting) bolts are pulled and rifles are racked verically in the shade, I think this creates a "chimney effect" and allows them to cool.