barrel heat, and cleaning question

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onlybrowning

New member
I have always tested loads by shooting 4 or 5 shot groups, and thoroughly cleaning between each group. I am finding with my new rifle, my gun shoots about 2 inches left and about 1 inch low with the first round. How many shots can I safely assume during testing are going to be true before fouling decreases accuracy? Remember, I am trying to keep variables constant when testing powder charges.


Also, how hot does a barrel have to be to affect accuracy? My Browning A bolt .325 WSM gets warm with one shot, warmer with 2, and the third is quite warm. By the fourth shot, you cannot touch the barrel. Am I letting the barrel get too hot to test for accuracy of a particular load? Does it have to be completely cool or just not really hot? I have not heard any consistent answers from anyone I know. :confused:
 
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rwilson452

New member
With your .325 I would suspect that you would need 15-20 shots before accuracy is affected. you want to shoot each shot with the barrel at the same temperature you will be expecting it to be in the field. For a hunting rifle that would be stone cold. As you test loads you going to have some left over that you don't fire. EG. your seeking a sub moa group you make up five of each. if the first two group at 3" your group will not gt better with more shots. put the other 3 away for future barrel fouling. next time at the range fire 4 or 5 of these to foul the bore. then begin testing, letting the barrel totally cool between shots. Remember if you have a blued barrel and it's out in the sun it will get hot just from the sunlight so put it in the shade. When it feels to be close to the air temp its in shoot another round. Yes it's very slow work. It time you will be able to tell a bit closer how many shots you can get off beore you need to clean the barrel. With some rifles minor amounts of copper fouling won't bother it so you can just run a bore snake down the bore to knock out most of the powder fouling. As your rifle is a unique thing unto itself YMMV



I have always tested loads by shooting 4 or 5 shot groups, and thoroughly cleaning between each group. I am finding with my new rifle, my gun shoots about 2 inches left and about 1 inch low with the first round. How many shots can I safely assume during testing are going to be true before fouling decreases accuracy? Remember, I am trying to keep variables constant when testing powder charges.


Also, how hot does a barrel have to be to affect accuracy? My Browning A bolt .325 WSM gets warm with one shot, warmer with 2, and the third is quite warm. By the fourth shot, you cannot touch the barrel. Am I letting the barrel get too hot to test for accuracy of a particular load? Does it have to be completely cool or just not really hot? I have not heard any consistent answers from anyone I know.
 
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onlybrowning

New member
Oh man. I have been doing it wrong for a long time now! I must have gotten lucky with my .270 because it shoots really well perfectly clean, and I can shoot a 4 or 5 shot group in .6" or so before the barrel heat is too much. Then I can clean it and do it again. After 5 shots or so in about 6 or 7 minutes, the barrel gets hot enough to affect accuracy. Your method certainly does sound like a better test, and I will try it starting tomorrow or Wednesday. Thanks a lot.
 
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snuffy

New member
There's a lot to be said for testing in the same conditions that you will be using that ammo in. But realistically you just can't do it. Like the old adage, shoot from a clean bore if that's what you hunt with. Load work-up in the summer, then hunt in fall conditions,(usually colder), is NOT the same conditions.

With todays smokeless powder and non-corrosive primers, we do not have to clean right away to prevent rust. So we can leave her dirty and not suffer any consequences.

If I'm working up a load, I shoot slow enough as not to cause barrel damage. By that I mean if I can't grab the barrel hard and be able to hold on for five seconds without being forced to let go--it's too hot. If I can, then I shoot another round.

I don't clean between 5 shot groups. I seldom even take the cleaning kit with me to the range. I start with a clean bore, then fire a couple fouling shots to get it dirty. Then commence the load tests. When I find the load I want, I leave it dirty if I'm going hunting soon,(like in the next couple weeks). If it will be longer, then I clean at home, then go to the range just before leaving for the hunt to foul the barrel and check sight-in.
 
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Scorch

New member
Why would you clean between groups? When I first read the post, I thought someone was talking about black powder cartridges. With smokeless powder, you should be able to shoot 50-60 rounds before you notice a difference from fouling. Your first shot or 2 after cleaning a barrel will go to a different point of impact than the following shots or preceding shots. You will never know if your rifle is sighted doing it like that. If you are trying to sight in the rifle, clean it when you get home.

If your barrel is hot to the touch, it's too hot. Always let your rifle cool between shots when firing for group, especially with a round like the .325 WSM that burns 75-80 gr of powder at a whack. Even if this means letting the rifle sit for a minute or two, let it cool down between shots. With my 8mm Rem Mag, I used to let the rifle sit for 4-5 minutes between shots when sighting it in.
 
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onlybrowning

New member
I tried the loads at the range today letting the barrel completely cool and I let it get dirty. Well turns out you guys were right again! I got all four test loads under one inch and one group measured exactly 3/8". I am very excited to hunt with this gun now.

ps: I am full length sizing and using specified COAL from the manual. The bullet is a Nosler BT 180gr, Winchester brass, H-4350, and Fed 215M primers.
 
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Linear Thinker

New member
"Fouling shot" concept has been around for a while. It's important to know where your 1st round from a clean barrel will go.
I keep a log. My 1st shot is usually 1-2" away from the group that will follow it.
LT
 
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MADISON

New member
Barrel heat?

Are you having the same rouble I am having with my Ruger .223 Ultra-Lite?

With 27.5 grains of Win. 748 [55 gr. bullet] I get a 3 1/2 inch group. To get a dime size group out of my "pencil thing barrel", I had to drop the load from 3200 fps down to 2600 fps. That is 21.5 grains of Win. 748 and it shoots well.
 
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