Load test wait times.

[FEENIX]

I usually shoot when it's 30 degrees or colder. Barrel cools in less than one minute. Then reload the most accurate loads and shoot them again when temperature warms up in the spring. It takes a little longer, but I am old and not in a hurry.

LOL! I agree load development is not a race.

 

[shinbone]

For me, shooting the bigger magnums, I wait about 1 minute between shots. And that's more for barrel life preservation than anything else. I am just an accuracy minded hunter, so squeezing the final .01% of accuracy out of my gun is something I don't worry about.

I have my Labradar setup so the screen goes blank 1 minute after the last shot. It then stays armed for another 30 seconds. It is during that 30 second time period that I take the next shot. During that 1 minute, I extract the spent case, check it for pressure signs, write down the velocity readout, and put the next cartridge on the follower. That makes it easy to maintain a slow and steady shot rate to minimize heating the barrel. Once I find a load, I will do a few quick 3-shot strings to gauge how the load will perform in the field. I know it is not perfect, but for me that seems to be the best balance of the various competing factors.

 

[eoperator]

Enter your load data on 'Barrel life calculator' it will give a recommended shot rate time. If that info is correct .223 ~30sec, 6cm ~60sec, 300wm ~80sec.

 

[just_jon]

I tend to get carried away and don’t take a lot of time between shots. i was looking at some chrono data from my last range session and noticed most five shot strings were fired in less than 3 minutes. I shot two test groups with my 300WM that day that were sub .3” @100 yards and am now wondering if they could have been even better if shots were spaced out. Heading back to the range on Monday and see if 5 minutes between shots changes results.

 

[jrock]

Before I started using barrel coolers, on cool days, 3 minutes was enough between shots. 4 to 5 minutes in the heat of the summer, and in the shade. That is for sporter barrels with big game hunting cartridges. I highly recommend cooling your barrel with the bolt open in the vertical position. Hot air rises and it pulls air through the barrel faster.

When I do a ladder test, I shoot about 20 rounds. 20x3 = 1 hour. With a good barrel cooler, I can cut that time down to twenty minutes. I also tend to shoot several guns at the same time so that helps with the wait times.

I had a coworker tell me, "life is too short to eat burnt popcorn." I have found since using barrel coolers, life is too short not to use a barrel cooler. The barrel coolers we make cut that 3 to 4 minute time down to a minute. I like to use a usb battery pack with multiple outlets and run multiple coolers at the same time.

 

[Varmint Hunter]

On a cool morning I'll wait a minute or two between shots while using a barrel cooler. I'll wait a bit longer between 3-shot groups. I frequently wrap my hand around the barrel just forward of the chamber to monitor barrel temperature. Once you notice it's getting a bit too warm (not hot), I'll stand the rifle in the rack and grab another rifle while the cooling gun returns to ambient temperature. Magnums will always require MORE cooling time between shots and between groups.

 

[Gingerman]

Kimber 84 Hunter with pencil barrel gets two shots in relatively quick succession, then cool off completely while I OCD shooting my other guns.

Bro got him a heavy palma tho. Something like that I just make sure I can still grab the barrel without pain.

 

[Doom2]

it's hard to fathom shooting a 6 grain range with 5x0.2 gr increments in a 45 grain cartridge. The likelihood of finding an acceptable load on the lower half of that range is highly unlikely unless you are looking for a low recoiling round. If that's the case then the higher end is where you don't need to go. If you're concerned about pressure then load and shoot one round in 1/2 gr increments until you get to about 93-94% of book maximum then do your testing.

 

[Mike Matteson]

I set up with a CO2 20lbs can to cool my barrels. It's pricesee, but it get the job done. I would work up and see by one load for each powder increase. Looking of pressure signs. At the same time you can do a ladder test. I set a very long time ago and did what you are setting up to do. A waste of components. The 0.2 increase is ok on smaller powder chargers, like you are loading for, but only one round and step up. The only other thing, is the powder temp sensitivity? If so you need to see in another test for pressurs signs in the summer to see how it reacts to temp. On larger cartridges you can move up .5gr at a time. I will load from the low loading powder loads in a manual and move up. I go until I hit the pressure signs. Heavy lift or ejector marks on a case base. I generally I watch for flatten primers and stop there. I am generally over the high powder loads in the manual at that time anyway. I am somewhat different because of looking for velocity. I note the ladder test and then work on accurate loads. I try and keep my rifles in the 3200 to 3300 fps ranges. Bullet drops are about the same, and I am looking at 500yds max shots.

 

[Noidly1]

I suppose it depends on the ambient temperature while you're shooting.

In general I like to fire the 3 to 5 round group at nearly the same time. That is to say something like 30 seconds between shots. Then let the barrel cool for 5 to 15 minutes before starting the next group.

It sounds like you have a lot of cartridges to shoot. How many shots can you fire accurately before fatigue sets in? I would have to break up shooting 155 rounds accurately over four range sessions. I would also want to clean the barrel half way through that.

Good advice. I am not looking for accuracy just yet. I am just trying to find all of the nodes and will pick one in the middle I think and then tune the load for that node for accuracy.

OK. I ask because I let my hunting rigs cool pretty good between every two shots. Mimic the cold bore shots for hunting. Range/competition gun I keep the gun cool enough, but pay attention how its doing with warmth on the barrel.

A suggestion. You can limit component expense by first finding pressure with your selected powders, and getting an idea in that phase which powder is working the best. Then back off a grain and start the tuning by seating depth in 2 spots. Just off the touch of the lands, and .020 off. Trying to limp a non cooperating powder by eeking on it .2/10ths a grain is a waste of time, money, and money. You are turning cash into noise! LOL

This is not a bolt rifle so I am restricted on COAL. With my combo I have a .050 jump.

it's hard to fathom shooting a 6 grain range with 5x0.2 gr increments in a 45 grain cartridge. The likelihood of finding an acceptable load on the lower half of that range is highly unlikely unless you are looking for a low recoiling round. If that's the case then the higher end is where you don't need to go. If you're concerned about pressure then load and shoot one round in 1/2 gr increments until you get to about 93-94% of book maximum then do your testing.

As above, I am just trying to find all of the nodes and will pick one in the middle I think and then tune the load for that node for accuracy. Most likely I will probably not go past 44grns anyway.

I set up with a CO2 20lbs can to cool my barrels. It's precise, but it get the job done. I would work up and see by one load for each powder increase. Looking of pressure signs. At the same time you can do a ladder test. I set a very long time ago and did what you are setting up to do. A waste of components. The 0.2 increase is ok on smaller powder chargers, like you are loading for, but only one round and step up. The only other thing, is the powder temp sensitivity? If so you need to see in another test for pressures signs in the summer to see how it reacts to temp. On larger cartridges you can move up .5gr at a time. I will load from the low loading powder loads in a manual and move up. I go until I hit the pressure signs. Heavy lift or ejector marks on a case base. I generally I watch for flatten primers and stop there. I am generally over the high powder loads in the manual at that time anyway. I am somewhat different because of looking for velocity. I note the ladder test and then work on accurate loads. I try and keep my rifles in the 3200 to 3300 fps ranges. Bullet drops are about the same, and I am looking at 500yds max shots.

I here ya, I have, what I could get at the time, is Accurate 4064 and I do not know how tempurature sensitive it is but it is what I have to work with. I like the CO2 idea but wonder if it would get the barrel too cold. As far as fps goes I'm probably looking in the 25-2600 or so range.

 

[Noidly1]

Just a heads up, I probably could have lead with my build. My bad...
LR-.308
20" fluted heavy Palma barrel.

Below are the goodies I could get at the time during the "scare"...
Accurate 4064
Regular Fed cases
Standard Fed 210 primers
175 SMK's

I'm not looking for barrel burning performance but a load that will give me the best accuracy for what I have.

Thanks.

P.S. The guy that mentioned about putting a cool rag on his barrel. If that can be done, could I have a bucket of water and pour some over the barrel after each shot so it doesn't get a chance to get warm or will I be taking a chance of warping the barrel? I know if the barrel is hot and you do that the barrel will warp but if I don't let it get warm, will this be ok???
Just looking at ways of shortening the time it is going to take to go though all of those rounds. If I have to wait 5 minutes between each round, that could take a half hour for each load and I'm looking at 15 hours. Then if I split it up in a few days, that means a week or two between each session which means the weather will be different for each session. Bummer....

 

[Gingerman]

Just a heads up, I probably could have lead with my build. My bad...
LR-.308
20" fluted heavy Palma barrel.

Below are the goodies I could get at the time during the "scare"...
Accurate 4064
Regular Fed cases
Standard Fed 210 primers
175 SMK's

I'm not looking for barrel burning performance but a load that will give me the best accuracy for what I have.

Thanks.

Do you have an adjustable gas block? I think you will get forward ejection of brass and ejector smears on the heads past 41.5gr. Unless you can gas it off with an adjustable gas block.

You want the cases ejecting 90 to the port or just slightly behind. If muzzle 12 o'clock, 3:00-3:30 brass ejection is optimal.

 

[Noidly1]

Do you have an adjustable gas block? I think you will get forward ejection of brass and ejector smears on the heads past 41.5gr. Unless you can gas it off with an adjustable gas block.

You want the cases ejecting 90 to the port or just slightly behind. If muzzle 12 o'clock, 3:00-3:30 brass ejection is optimal.

Yes I do. Thanks for the heads up! I have it adjusted for that with factory Fed 175 SMK's. Thanks.

 

[jrock]

P.S. The guy that mentioned about putting a cool rag on his barrel. If that can be done, could I have a bucket of water and pour some over the barrel after each shot so it doesn't get a chance to get warm or will I be taking a chance of warping the barrel? I know if the barrel is hot and you do that the barrel will warp but if I don't let it get warm, will this be ok???

I have dunked a barrel in a tall bucket of water when fire forming brass. I did it when the barrel got hot enough that I didn't want to touch it. That barrel shoots in the 0.2s. Just make sure you clean all the water out of the bore before shooting or bad things can happen.