Teach me about 22LR fouling? Littlepod is gonna LOL at this follow-up report on my "search for a scope"...

unrepentant

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If you just wanna skip directly to the question, start below the line of plus signs. for "background", just continue here: Back in November I posted a thread asking for advice for a friend--I needed a quick education on scopes for a 10/22, and what semi-auto platforms (10/22s) were the best options. He ended up buying an Athlon EP5 for his Ruger Takedown. I couldn't steer him from his "camp-gun" jones.

Several suggestions however tangential, were given to me so's I could try to convince him that a 'Takedown' and accuracy aren't compatable... HOWEVER. *I* was listening. kind of... I favored semi-auto over the bolt suggestions out of sheer funk.

I ended up buying a used KIDD Classic; I mounted a Nightforce NXS I've had in the safe for the last 20 years. After hours and hours of researching this forum and Rimfirecentral, I can't find an answer or even mention of my specific problem, so I'ma pose the question here...
+++++++++++++++++++++++++++++++++++++++++++++++++++++

I've settled on two different rounds that shoot well enough for my desires--SK Long Range Match and Wolf Match Extra. I tested 8 different OEM loads by shooting FIVE 5-shot groups of each ammo load at 50 yards. It's not worth listing them all.

I only intended to shoot FOUR 5-shot groups, but something seemed to happen very consistently and forced me to shoot a "fouler" group for each OEM load--because these first foulers shot anywhere from 3-5 times larger than the rest of the four 5-shot groups.

As an example, I brought the cleaned rifle with a stone-dry bore to the range and started a fouling group as I expected it to need, shooting 40-some rounds of Remington Golden Bullets as cheap foulers until its' groups seemed to tighten up (or I was getting used to the new rifle). I then fired the first 8 rounds of Wolf Match Extra at the first target of the 5-target row intended for "Wolf ME testing"--disbelievingly-- because its' group size was about 1.75" (lots of posts touted Wolf ME as "acceptable", so I expected better groups than Remington Gold out of the KIDD). But since the last three shots of that 8-shot group were almost touching, I proceeded to shoot the other four 5-shot groups in that row, and the largest group was .587".

For the next row (SK Long Range Match), I shot the first target expecting that the rifle was very well-fouled now, which I thought was proven by the tighter Wolf groups in the row above. But the first SK LRM target was "huge" too, shooting .854" with 11 shots. Talk about Pissed OFF and broken-hearted over the cost of ammo... However, it's last three shots had tightened up, so I proceeded to shoot the next four 5-shot groups--.267", .303", .198", .254", .303". Man, was I relieved...

This regimen--large 8 or more- shot fouling groups was consistent throughout the different 8 brands of 22LR ammo that I shot; after each OEM "ceased fouling" the rest of that OEM got much tighter--but each and every OEM needed to be fouled first.

Does that make sense? My only experience is large caliber rifle... there, generally a 3 or 5-shot group fouled the barrel for the rest of every load for that day's session. I never had to "refoul" for a different load in an already-dirty bore. If this makes sense, can someone explain it? I didn't take breaks between different OEMs and I can't figure it out.

Thank you!
 
Nothing new, its been that way for 100 years.
Your different ammos have different waxes and oils on them as a lube so the lead doesnt gum itself to the steel.
Once you get a consistent layer of lube down for a given type of ammo you will start to get consistent results out of that type.
This☝️
 
In order to save on ammo, I "prefoul" my bore by using SPG black powder cartridge lube on a patch and run it through the bore. It seems to help on some types of ammo, especially Eley, as they use similar lubricants on their bullets. I think it drastically cuts down on the amount of rounds I have to send down range to get my bore refouled to a consistent level. I lightly rub some of the lube into a patch and run it through the bore a few times after I clean the barrel/chamber.

I shoot .22 benchrest and clean my barrel after every card, so I always start a new card with a bare metal bore. Using my "prefoul" method, after shooting 3-4 rounds on a sighter, I'm ready to shoot for score.
 
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If you just wanna skip directly to the question, start below the line of plus signs. for "background", just continue here: Back in November I posted a thread asking for advice for a friend--I needed a quick education on scopes for a 10/22, and what semi-auto platforms (10/22s) were the best options. He ended up buying an Athlon EP5 for his Ruger Takedown. I couldn't steer him from his "camp-gun" jones.

Several suggestions however tangential, were given to me so's I could try to convince him that a 'Takedown' and accuracy aren't compatable... HOWEVER. *I* was listening. kind of... I favored semi-auto over the bolt suggestions out of sheer funk.

I ended up buying a used KIDD Classic; I mounted a Nightforce NXS I've had in the safe for the last 20 years. After hours and hours of researching this forum and Rimfirecentral, I can't find an answer or even mention of my specific problem, so I'ma pose the question here...
+++++++++++++++++++++++++++++++++++++++++++++++++++++

I've settled on two different rounds that shoot well enough for my desires--SK Long Range Match and Wolf Match Extra. I tested 8 different OEM loads by shooting FIVE 5-shot groups of each ammo load at 50 yards. It's not worth listing them all.

I only intended to shoot FOUR 5-shot groups, but something seemed to happen very consistently and forced me to shoot a "fouler" group for each OEM load--because these first foulers shot anywhere from 3-5 times larger than the rest of the four 5-shot groups.

As an example, I brought the cleaned rifle with a stone-dry bore to the range and started a fouling group as I expected it to need, shooting 40-some rounds of Remington Golden Bullets as cheap foulers until its' groups seemed to tighten up (or I was getting used to the new rifle). I then fired the first 8 rounds of Wolf Match Extra at the first target of the 5-target row intended for "Wolf ME testing"--disbelievingly-- because its' group size was about 1.75" (lots of posts touted Wolf ME as "acceptable", so I expected better groups than Remington Gold out of the KIDD). But since the last three shots of that 8-shot group were almost touching, I proceeded to shoot the other four 5-shot groups in that row, and the largest group was .587".

For the next row (SK Long Range Match), I shot the first target expecting that the rifle was very well-fouled now, which I thought was proven by the tighter Wolf groups in the row above. But the first SK LRM target was "huge" too, shooting .854" with 11 shots. Talk about Pissed OFF and broken-hearted over the cost of ammo... However, it's last three shots had tightened up, so I proceeded to shoot the next four 5-shot groups--.267", .303", .198", .254", .303". Man, was I relieved...

This regimen--large 8 or more- shot fouling groups was consistent throughout the different 8 brands of 22LR ammo that I shot; after each OEM "ceased fouling" the rest of that OEM got much tighter--but each and every OEM needed to be fouled first.

Does that make sense? My only experience is large caliber rifle... there, generally a 3 or 5-shot group fouled the barrel for the rest of every load for that day's session. I never had to "refoul" for a different load in an already-dirty bore. If this makes sense, can someone explain it? I didn't take breaks between different OEMs and I can't figure it out.

Thank you!
I completely agree with the reply's so far. You need to foul your gun with the same ammo you are shooting, But there is another way of looking at your problem. You said your gun already had several rounds run through it so it was already fouled so that first shot is not really a fouling shot ,just your first shot is always a flyer. Try the same lube thing and see if that corrects your problem. If it doesn't let us know. I've built close to 10 custom 10/22s and run into just about every problem you could imagine. It's a love hate relationship!
 
I'll echo for another data point. I would foul in with 20-25 rounds on my vudoo after switching between center x Or midas and after cleaning the barrel. I only mention those two because those are the ones I would exclusively shoot. I would also clean the rifle between lots of ammo as well and subsequently foul back in after that.
 
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I completely agree with the reply's so far. You need to foul your gun with the same ammo you are shooting, But there is another way of looking at your problem. You said your gun already had several rounds run through it so it was already fouled so that first shot is not really a fouling shot ,just your first shot is always a flyer. Try the same lube thing and see if that corrects your problem. If it doesn't let us know. I've built close to 10 custom 10/22s and run into just about every problem you could imagine. It's a love hate relationship!
Mine doesn't seem to be a single 'first shot flier' problem. When I changed from SK Long Range Match to Wolf Match Extra, it took 10 rounds of W-ME to "reset" the bore (10-shots = 1.8", with the last 3 shots in the group less than about .5"); 20 more W-ME shots later (four 5-shot groups < .642"), I switched to CCIs and that load took another 8 to tighten up from a 1.24" 8-shot group to < .748s. That regimen seemed pretty constant throughout my testing. Each initial large "fouling group" (no matter the number of shots) would gradually tighten up and the remaining four 5-shot groups were at least 1/4 smaller than the fouling spread. Thank you.
 
To continue the discussion in regards to laying down a coating of the fouling from the ammunition you'll actually use:


The target below was shot @50yds with a pencil-barreled Remington 580.
It has a compact Pentax mini 4-12X and a beyond horrible trigger that must be 9lbs or more.
The groups were shot over Cordura bags, so maintaining a good hold was difficult to say the least.
It needs either better bags or a bipod, but I'm reluctant to drill it for a stud.

I used 7 or 8 shots of the SK to get a decent zero and then shot the three groups on the bottom as they are numbered. Yes, I did correct impact point before the second group. No changes were made after that.

By all appearances, as I was shooting the third group, velocity went up.

Notice that the group sizes were relatively the same with the exception of the lowest shot on group three. Remember the previous 7-8 "foulers."

Next up was RWS Target Rifle.
Groups shot were left to right. Bigger to smaller.

Last was Norma Tac. By the third group, it started to settle down. Just as I started the fourth group, the winds picked up to 5-7 mph from the 6:00. Group size immediately went to shit.

Like you, (and most others) I noticed after a group or two, the gathering would begin and get better as groups were fired.

I've heard that RWS and SK use the same coating, but in this case I'm pretty sure it's not true.

I have shot SK and Lapua with no seasoning issues though.

20230220_065556.jpg




20230220_070748.jpg
 
Jesus Christ .22lr is so much more involved than I thought it was lol.
It can become a very deep rabbit hole if you allow it. Its definitely a two sided rounds, I’ve spent like two hours compiling data point to put into a spread sheet to track speed/group size for PRS stuff and then the next time out just blasted stuff at 50 yards till my heart was content.
 
Rimfire fouling?

Did you know that immediately after pulling the trigger and the bullet exits the muzzle,
the surface of the bore is coated with wet burn residue and partially combusted primer/powder?
It's mud...gooey, sticky, grey, ash mud. Clumps and smears of mud all over the rifling from leade to muzzle.
You can verify this y'erself by pushing a nylon brush though the bore immediately after firing a shot.
The brush will come out coated with wet clumps of the fouling. That wet surface changes how bullets
interact with the rifling with each shot sent. Wait too long between shots, the mud drys out.
That dry crust can shift the trajectory as compared to the wet bore.
 
I can’t figure how to share it, but Brian Litz posted a slo-mo video (on Facebook) of a .22LR leaving the muzzle and tracking beside a tape measure.
Some things that stood out to me, the “blast” appeared to stay the diameter of the barrel, flowing behind the slug till dissipating. Even more interesting was the crud pushed out by the slug. It stayed attached to the ogive till about 10” out and then sprung off almost like a shattered halo.
I would love to see tests with different ammo and rifling styles, not to mention bore lengths, to see what effects they have on this phenomena, and if it correlates to accuracy.
 
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I can’t figure how to share it, but Brian Litz posted a slo-mo video (on Facebook) of a .22LR leaving the muzzle and tracking beside a tape measure.
Some things that stood out to me, the “blast” appeared to stay the diameter of the barrel, flowing behind the slug till dissipating. Even more interesting was the crud pushed out by the slug. It stayed attached to the ogive till about 10” out and then sprung off almost like a shattered halo.
I would love to see tests with different ammo and rifling styles, not to mention bore lengths, to see what effects they have on this phenomena, and if it correlates to accuracy.
 
I would foul in with 20-25 rounds on my vudoo after switching between center x Or midas and after cleaning the barrel. I only mention those two because those are the ones I would exclusively shoot.
Have you observed a POI shift or shot-to-shot spread when switching from Center-X to Midas+ and then back to Center-X, or M+ --> C-X--> M+?

I ask because these rounds literally come off the same machines and use the same lube - Devan at the AZ Lapua test center told me all the SK and Lapua flavors except biathlon use the same lube.

So, I would be very surprised to see a shift/spread related to lube. I have verified that I can switch back and forth between my old lot of Lapua-sourced Wolf Match Target (rebranded SK Standard+) and lot-tested Center-X without affecting each one's specific POI/spread.

(Note: the preceding applies to my 4-year-old Vudoo with 20" Ace/Kukri barrel. I am in process of breaking in a RimX with 22" Shilen/Heavy Varmint barrel; so far, it appears that I don't see any POI/spread differences with this one either as I switch among several lots/flavors of SK and Lapua ammo. Again, let me emphasize that, of course, each has its own specific POI and group-size "profile;" what I'm saying is that I can go from Center-X to Standard+ to Long Range to Midas+ to... and back... and each label will reliably shoot to its known POI and "group size" without "fouling.")

Fwiw.
 
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Have you observed a POI shift or shot-to-shot spread when switching from Center-X to Midas+ and then back to Center-X, or M+ --> C-X--> M+?

I ask because these rounds literally come off the same machines and use the same lube - Devan at the AZ Lapua test center told me all the SK and Lapua flavors except biathlon use the same lube.

So, I would be very surprised to see a shift/spread related to lube. I have verified that I can switch back and forth between my old lot of Lapua-sourced Wolf Match Target (rebranded SK Standard+) and lot-tested Center-X without affecting each one's specific POI/spread.

(Note: the preceding applies to my 4-year-old Vudoo with 20" Ace/Kukri barrel. I am in process of breaking in a RimX with 22" Shilen/Heavy Varmint barrel; so far, it appears that I don't see any POI/spread differences with this one either as I switch among several lots/flavors of SK and Lapua ammo. Again, let me emphasize that, of course, each has its own specific POI and group-size "profile;" what I'm saying is that I can go from Center-X to Standard+ to Long Range to Midas+ to... and back... and each label will reliably shoot to its known POI and "group size" without "fouling.")

Fwiw.
That good ol NAMMO made Wolf MT was THE most consistent ammo I’ve ever shot in all my rimfires, really incredible stuff. I should have sold toys and purchased pallets of the stuff when it was available.
 
Jesus Christ .22lr is so much more involved than I thought it was lol.
22LR is a beautiful mess, and due to a number of things my mess might be different than your mess..but to complicate it even more, even though our messes might be different there are somethings about all of our messes that are the same..like I said, it’s a beautiful, fun mess, that last a lifetime.
 
Truth, below a certain size it begins to cost you cubic dollars for very little improvements that you barely notice.
At what size and distance would you consider it to start costing cubic dollars?
I think many Cz, Tikka, Bergaras seem to be reliable 1 MOA at 50 yds and 1.75 MOA at 100 yds guns. So for me, anything shooting below .380" at 50yds or 1.00" at 100 yds gets to that money pit pivot point.
YMMV, happy shooting.
 
At what size and distance would you consider it to start costing cubic dollars?
I think many Cz, Tikka, Bergaras seem to be reliable 1 MOA at 50 yds and 1.75 MOA at 100 yds guns. So for me, anything shooting below .380" at 50yds or 1.00" at 100 yds gets to that money pit pivot point.
YMMV, happy shooting.
That would be F-class where you’re chasing the tightest group possible, and bench rest isn’t to far behind. Then on the other side of the coin are the guys pushing distance while chasing tiny groups.
 
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The most irritating part of rimfire, is that the results are dependent on mass produced ammunition.
The quality and uniformity of the cartridges
determines the predictability and consistency of the trajectories.
No two cartridges are identical.
Which means a box that produced sub moa at 100 yards today
doesn't mean the next box from the same brick will do so also. :(
The variations in components and assembly is the reason why.
The best method of ensuring consistent results with rimfire?
Minimize the distance from muzzle to target.
Cheapest, easiest, most effective technique I've found. ;)
 
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I have found that when I switch ammo it takes almost a whole box to settle in and group well. Also the more you shoot the tighter it will get. After 300 round of the new Eley I tried I am now ready to buy a small pile of it. It takes a while but you really don't know how things will shake out until it happens. My experience is similar to everybody elses, but i also say to shoot a few hundred rounds to make sure. Don't shoot 50 of one and then 50 of another. Shoot 150+. I think it makes a difference.
 
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