Fouling a rimfire barrel.??

[native hunter]

G"day All,
Constantly around the ranges and internet sites theres lots of talk on Barrel fouling and cleaning that pops up regularly.
Now im no expert here and this is my assumption only that when a barrel requires a heap of fouling shots to shoot to POA that it must be a roughly finished barrel if thats what it requires to come up to scratch.
My theory is that it takes a few shots and sometimes several to fill the imperfections in the tube before it starts to show promise.
This can usually be seen with the lower end rimfires that have roughly manufactured barrels.
On the other hand a good custom barrel will usually shoot one shot of group and then straight to POA.
I have noticed this with my current rifle with a maddco barrel,it printed first cold clean barrel shot high and then to POA, as it got up around the 1500 shot mark this phenomenom disappeared and it now shoots to where you point it from cold and clean.
Any thoughts on this out there.??
Regards
native.

[petevm]

This is the easiest of all! Just do what the barrel tells you to do!! My rimfires get a light squirt of spray oil after a match and one dry patch before the next. Usually takes less than 5 shots to get it grouping again. Loaned one to a mate one time who diligently cleaned it after his match - cost me a packet of ammo to get the bugger shooting again. Most rimfires like a 'seasoned' bore to shoot their best.
Pete

[native hunter]

G"day Pete,
"Seasoned " I assume could be the barrel having a film of bullet lube/wax layed down before it comes good.
Im told that every shot leaves roughly an inch of "seasoning" in the barrel.
I have a 26 inch barrel on my rimfire and it does not require 26 shots to shoot well.
I also believe the cleaning regime has lots to do with it,as you say if its done differently the barrel will act out of character,I can tell if my gun needs tuning by just this,if its not on its game straight up,I know somethings not right.!!
These rimfires are temperamental bastards, one day you can shoot really well and then next night shoot very average.!!
Im having lots of fun chasing rimfire perfection(although its sending me broke..!!).
Regards
native

[petevm]

I repeat - do what your barrel tells you it is happy with and don't try to figure out why (unless you want to end up in the 'Looney Bin").

[native hunter]

Pete,
"Looney Bin",if im counting centres when trying to sleep i think im almost there.!!
Regards
native

[SnipeWench]

NH,

My FWB w/ Lilja barrel does the same - first shot high, then straight to POA.

I'm a bit lax with my cleaning regime, but it hasn't bitten me (yet) - sometimes I scrub and patch out, othertimes I just put it away!

I've found that some batches of ammo are better than other batches, with regard to the first and subsequent shots. My X-Act batch #173435, the first shot is high on a cold barrel, then straight to POA.

Batch #157445 shot high, then would shotgun for about 5 to 10 rounds, and then settle down to a group around the POA. This was shown in the NSW Enduro, when I ran out of the #173435 at the end of the first detail. The second detail of 60-shots came up, and I had to change to the #157445. I was nervous shooting this batch, as I'd not shot it before, and it shotgunned for around 20 shots. I sat back, thought about life being so cruel in rimfire sports for a minute or so, flicked the computer over to score, then shot a nice tight 60-shot grouping for a 599 score. The difference between the sighters and the scoring shots were chalk and cheese!

So even the good barrels can have problems with batches of ammo. I couldn't work out the reason why this batch was different to the barrel, and required lots more shots to get it to the sweet spot, but I did know right from the first shot that Lapua had changed the powder composition - this #157445 was an acrid smell, with black smoke, whereas the #173435 lot was a sweet smell, with a whitish smoke.

[Brett33]

I start every target with a clean barrel, at the end of a target while the wax is still hot I push a wet patch through, then 2 dry.
Before a major match or after about 200 rounds I also use a Bronze brush to remove the carbon, 1 or 2 passes with the brush starting at the crown and pulling it towards the chamber.

First shot is always high, after testing ammo lots with my Chrono, i found that the clean barrel was 25 to 30 fps faster, after that all was good and ready to group. In a big match I always put another 5 down on the sigters to be certain all is ready.

Brett

[native hunter]

Brett,
why use the brush from the crown to the breech.??
Drags all that rubbish back into the action.!
Regards
Native

[Brett33]

Brett,
why use the brush from the crown to the breech.??
Drags all that rubbish back into the action.!
Regards
Native

The theory is that I have cleaned most of the rubbish out with the wet and dry patches, all that is left to worry about is the carbon build up at the front of the chamber on the leade (sp), this is often called the carbon ring. On my chamber this is a 2 degree taper. I see no value in try to force the carbon up the the 2 degree slope and through the barrel, instead I pop the ring into the action.
You are correct this makes a mess in the action, A mess I can clean, a scratch down the bore I can not.

Brett

[chris.tyne]

When I first cast a stone into the rimfire BR pond I had little to no idea about the frequency of cleaning a barrel so i cleaned it after every detail cause that is what most seemed to be doing,then I started to ask and got the "Its easier to have a consistantly clean barrel rather than a dirty one"................................Hmmmmm Ok then I will ask another "Dont clean it cause the shot after the first one in a clean barrel will push all the crap out"..........................................can you spell confused.
So i tried the clean all the time and also the clean every couple of hundred rounds and noticed no difference,so considering that I wasn't constantly running the cleaning rod up and down the bore for no gain I decided to no clean at all and see what happened.
I found that different brands of ammo acted differently which I suppose came as no great surprise,Eley went into the hundreds of rounds before there was any accuracy degradation.
So like Peter said your rifle will tell you when it needs cleaning,with the carbon ring ......................well I ended up with a bent cleaning rod via the kids playing sword fights(broom handle beat the rod!!!!) so i cut it of and bent it at right angles so that when a brush is fitted to it and it is inserted in the chamber the 90degree part clears the butt of the stock,so with a little inox and a couple of spins and the carbon ring is gooooooooooooooone.
As I have said before take this with a grain of salt as it is just my observation over a number of years and I have won little bar a frozen chook at a raffle once.



Regards Chris.