Fouling shot before group testing?
- Thread starter ReloadKy
- Start date
I shoot several, not only to foul the barrel but also to warm it up to a temperature that I somewhat attempt to keep constant throughout the shooting session. I normally do 40-50 test rounds, after shooting 5-6 fouler-warmers. My method of maintaining barrel temp is highly sophisticated: if grabbing the barrel doesn't hurt, then it's not too hot.
1 fouling shot is a tradition from back before what today goes as benchrest accuracy was even a consideration. I mostly use 2 fouling shots if I don't know the gun, but if experience tells you the second shot is going where all the rest go afterward, then with that gun and powder you can probably get away with 1.
Two other considerations: I have not owned but have heard of barrels that build up copper so fast that their accuracy falls off after just 20 rounds. I've owned one that lost accuracy noticeably after 35-40 rounds.
I've also heard of barrels that didn't settle down until after 10 fouling shots. This also applies to a powder change. Experienced top match shooters have said that if you switch powders and don't clean in between, it can take up to ten rounds for the fouling pattern to settle and best accuracy to return. So, you need the fouling shots to be the same powder you are using for the group.
Your best bet to find these issues is to fire one shot each into a large number, say, 30-50, of identical small bullseye stickers and measure the location of each hole horizontally and vertically and get the average for each. Then use a magic marker to put a dot on the average location on each bull and see how far each hole is from it. Then eliminate last fifteen holes get the SD and record it. Then drop hole #1 and add hole #16. figure it again. Repeat for holes 2 through 17, then 3 through 18, etcetera, until you get to the set that includes the last hole. Make a graph of SD vs. Eliminated Hole Number. If you see the SD's tend to settle, note where they tend to settle. That's where the gun has really settled. If you see them starting to get worse and some included point at the other end, then you have a fouling build-up problem.
Two other considerations: I have not owned but have heard of barrels that build up copper so fast that their accuracy falls off after just 20 rounds. I've owned one that lost accuracy noticeably after 35-40 rounds.
I've also heard of barrels that didn't settle down until after 10 fouling shots. This also applies to a powder change. Experienced top match shooters have said that if you switch powders and don't clean in between, it can take up to ten rounds for the fouling pattern to settle and best accuracy to return. So, you need the fouling shots to be the same powder you are using for the group.
Your best bet to find these issues is to fire one shot each into a large number, say, 30-50, of identical small bullseye stickers and measure the location of each hole horizontally and vertically and get the average for each. Then use a magic marker to put a dot on the average location on each bull and see how far each hole is from it. Then eliminate last fifteen holes get the SD and record it. Then drop hole #1 and add hole #16. figure it again. Repeat for holes 2 through 17, then 3 through 18, etcetera, until you get to the set that includes the last hole. Make a graph of SD vs. Eliminated Hole Number. If you see the SD's tend to settle, note where they tend to settle. That's where the gun has really settled. If you see them starting to get worse and some included point at the other end, then you have a fouling build-up problem.
Probably everyone. Since I am meticulous, I always test strings. With in-depth fine tuning of a load I will load 22 rounds of the load. 1 Fouling shot, 2 five round groups. I then clean the barrel, 1 fouling shot, then 2 more groups. Will copper fouling begin to affect accuracy by 20 rounds in most rifles? No. But I do this anyway. See below for an extreme example of why.
I can attest to this. I purchased a Savage Axis for my son and it wouldn't shoot worth a darn. Finally discovered that it would hold a halfway decent group when clean, but after even 10 rounds it starts to open up some and by 20 1.5moa turns into 3. Most disappointing Savage I've ever had. Never had one that couldn't hold 1moa out of the box until this one. I'm going to firelap the bore on this one to see if that helps any. Otherwise, it gets an ER Shaw barrel.
And I just learned something. Never heard of that.
The 1st shot or 2 from any clean rifle that I've ever owned would impact at a slightly different POI than shots fired afterward. Usually not enough to be a major problem though. With most of my rifles I'm good for several hundred rounds before accuracy deteriorates enough for it to be a problem for me.
Don Fischer
New member
I don't shoot fouling shots but I don't get the barrel squeaky clean either tho I used to. Read somewhere years ago that you can get the barrel to clean and then you need to fire fouling shot's. Seem's to work well. all the powder residue get's out and a lot of the copper fouling, but not all. I an only a hunter and I don't fire anything to heat the barrel up before shooting for group's. Your first shot at game is likely gonna be your best shot! If you need more than two, you probably messed up the first one and more than three, you'll probably never see the animal again to begin with!
There are cold bore/clean bore shots and cold bore/dirty bore shots. 3 different POIs for the same POA for most rifles
When you get a new load finalized the next time you go to the range with a clean bore you log where the first shot lands on target. Then when the bore is cold again but still dirty take another shot and log it. No two barrels will be the same and some will have more spread than others on that first and second shot but if all the other stars are aligned the same barrel should shoot in the same spot when the barrel is in the same condition.
I use stick on dots on graph paper for targets so it easy to hold off on that CB/CB shot even when using a scope with a plain jane reticle. Each of my rifles scope dope log contains the hold off for that loads initial shot. For a long range hunting that info is mandatory to know.
I do a final sight in check the week before a shoot with ten shots then leave the barrel dirty until after the shoot
When you get a new load finalized the next time you go to the range with a clean bore you log where the first shot lands on target. Then when the bore is cold again but still dirty take another shot and log it. No two barrels will be the same and some will have more spread than others on that first and second shot but if all the other stars are aligned the same barrel should shoot in the same spot when the barrel is in the same condition.
I use stick on dots on graph paper for targets so it easy to hold off on that CB/CB shot even when using a scope with a plain jane reticle. Each of my rifles scope dope log contains the hold off for that loads initial shot. For a long range hunting that info is mandatory to know.
I do a final sight in check the week before a shoot with ten shots then leave the barrel dirty until after the shoot
I shoot foulers. I have, and do, clearly see a point of impact change with my 22 lr match rifles. I will arrive on the line with a clean barrel and have tested this by not changing my sights. The first, second shots seldom land on each other.
I regularly blow a couple of foulers into the berm at a Bullseye Pistol Match. It does make a difference, the first shots out of a clean oiled barrel, hit a different point of impact.
For a centerfire rifle, this is tricky. You have to test and see if foulers are necessary. Before CMP Talladega, I shot in NRA matches, I shot the course of fire, and it always started at the 200 yard line in the standing position. With high mileage barrels, that I deep cleaned, removing all copper fouling, I could "see" a zero change as rounds went down range. But, considering I shot standing, and standing is a horrible position to use if you are trying to determine anything about accuracy, what I saw, could be bogus. But I saw it enough times, I think it was real. Therefore I do believe that the point of impact out of a new barrel is not as sensitive to barrel fouling as an old barrel.
However, since CMP Talladega, I have experimented with greased bullets, to see if my heavily greased bullets and cartridges have a stable point of impact, and I think they do, in the right rifle. This was a first shot down range, 300 yards, using established zero's with a known load. I made my best guess about the wind, and first shot was in the X. Yippie!
Point of impact did not change, I am going to claim, as the barrel fouled for a ten shot string.
This rifle is exceptionally accurate, and it may be non representative of the larger population of rifles.
I regularly blow a couple of foulers into the berm at a Bullseye Pistol Match. It does make a difference, the first shots out of a clean oiled barrel, hit a different point of impact.
For a centerfire rifle, this is tricky. You have to test and see if foulers are necessary. Before CMP Talladega, I shot in NRA matches, I shot the course of fire, and it always started at the 200 yard line in the standing position. With high mileage barrels, that I deep cleaned, removing all copper fouling, I could "see" a zero change as rounds went down range. But, considering I shot standing, and standing is a horrible position to use if you are trying to determine anything about accuracy, what I saw, could be bogus. But I saw it enough times, I think it was real. Therefore I do believe that the point of impact out of a new barrel is not as sensitive to barrel fouling as an old barrel.
However, since CMP Talladega, I have experimented with greased bullets, to see if my heavily greased bullets and cartridges have a stable point of impact, and I think they do, in the right rifle. This was a first shot down range, 300 yards, using established zero's with a known load. I made my best guess about the wind, and first shot was in the X. Yippie!
Point of impact did not change, I am going to claim, as the barrel fouled for a ten shot string.
This rifle is exceptionally accurate, and it may be non representative of the larger population of rifles.
3 foulers were what we were given in JROTC, one time I shot 2, then all my 3 position targets, then with the extra round I had, the top wire holding all the targets for the entire line.
One less fouler and shooting a bit faster seemed to help my scores vs everyone else that finished when their targets were rehung, after the repair...not actually cheating but definitely unsportsmanlike and if you win like that your not really “a winner”.
In any case it depends what you are doing. It’s pretty pointless to develop a hunting load using foulers as unless you have deaf animals you intend to shoot, that’s not how your going to do it.
FWIW I never take a fresh clean gun to a match or hunting, so I guess I am a “fouler” guy.
One less fouler and shooting a bit faster seemed to help my scores vs everyone else that finished when their targets were rehung, after the repair...not actually cheating but definitely unsportsmanlike and if you win like that your not really “a winner”.
In any case it depends what you are doing. It’s pretty pointless to develop a hunting load using foulers as unless you have deaf animals you intend to shoot, that’s not how your going to do it.
FWIW I never take a fresh clean gun to a match or hunting, so I guess I am a “fouler” guy.
After reading so many reports of barrels that wouldn't shoot to group w/o a fouling round, I've concluded, based on my experience, that those barrels are crap. I keep mine squeaky clean, as evidenced by a borescope, and do not own a rifle that does not print the first 'clean' round to POI.
For those who chose to shoot until it 'quits grouping', that's fine; you won't know, until you miss something! OK, I'll admit, I am not using any factory barrels, only custom barrels. Why brag or cry about mediocre products? Life is too short to cry about things that looked like a bargain, and delivered what they cost.
For those who chose to shoot until it 'quits grouping', that's fine; you won't know, until you miss something! OK, I'll admit, I am not using any factory barrels, only custom barrels. Why brag or cry about mediocre products? Life is too short to cry about things that looked like a bargain, and delivered what they cost.
There is this older dude that has a 22 LR single shot, open sights, that shoots the DNR range that I use. He has a target that had 6 rows of 6 bulls eyes. He sets it up at the 35 yard marker. He will take a shot and then run a bore snake through the barrel and then take another shot and repeat.
He only shoots 36 bullets for the three 15 minute sessions he is there. Every shot is dead center bulls eye. I asked him once why 35 yards? His reply was that was as far as he could see the bullseye now.
He only shoots 36 bullets for the three 15 minute sessions he is there. Every shot is dead center bulls eye. I asked him once why 35 yards? His reply was that was as far as he could see the bullseye now.
Thanks, that rifle is an exceptional shooter, and I only show the exceptional targets. I have pictures, some from last week, that are just awful. I may show them in a topic about long range shooting. Basically, you have to shoot the load at distance because how it performs close up, is no indication of how it will do, further out.
TheDevilThatYouKnow
New member
I think it depends on the ultimate goal.
If you're shooting competition (or for group size) then shoot a fouling shot.
BUT
If you're sighting in for hunting when your first and likely only shot is going to be from a clean, cold barrel, sight in from a clean, cold barrel. Why would you want to sight in for a bullet strike from a warm barrel when that's not where it's going to hit when you shoot a cold gun?
If you're shooting competition (or for group size) then shoot a fouling shot.
BUT
If you're sighting in for hunting when your first and likely only shot is going to be from a clean, cold barrel, sight in from a clean, cold barrel. Why would you want to sight in for a bullet strike from a warm barrel when that's not where it's going to hit when you shoot a cold gun?
a few months back I would have agreed with that however since I began experimenting with Cortina's 100 yard method I have became a fan. I used it in one match so far and the 583 agg was a good score for my shooting ability and the rifle I used. The load used has not been refined yet with COL and primer choice so it still has room for improvent.
here is a link if you are interested
Long range load development at 100 yards
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I agree with this and is exactly what I do with all my rifles excluding 22lr . Unless you have a specialty rifle that is designed to shoot one way and that's how you will shoot it every time . IMO it's best to know what your POI will be in all barrel conditions . For those that have many rifles it may be a bit much to know all that for every rifle owned . If that's the case , at minimum I recommend your favorite few should be doped to know where the POI is with clean cold bore , fouled cold bore and warm fouled bore .
Some goe as far as stance and or hold/position in each of those bore conditions . That's where I draw the line but see how it could help . I have a noticeable POI shift when using a bi-pod prone . That is likely because I have a back injury that makes that position very uncomfortable for me and I struggle with that shot . Which brings up another point . Some have those one or two positions that don't work well for them . It's not a bad idea to at least know if your POI changes when shooting in those positions even though you like don't shoot in those positions very often . You never know you might be forced to some day .
I have small 2 x 4 inch notebooks one dedicated for each of my main rifles. In each is round count for the barrel, scope dope for different loads, scope changes from session to session. Lets see last time I shot was I shooting at 200 or 300 ? For each load I also note the offset data for cold and clean and cold and dirty POI's. Keeps things straight for 2 dollars a rifle. I still put 2 off target before shooting my sighters however just to be on the safe side since I only shoot 3 sighters
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