Not right after cleaning

[Mikeflys]

Need your input on an issue with my Hatsan AT44-10 QE. After the first 500 pellets (give or take 100) I decided to clean the barrel. I used the string and vacuum cleaner method. Before cleaning I had nice round groupings. Take a look at these.



Every mag follows the same pattern, 1st shot is low, 2nd is right on, the rest fall between to 2 extremes. I have not yet tried a different pellet. These were all JSB's that this rifle was shooting extremely well before cleaning. Any ideas what I did or am doing wrong?

[BenjiHunter]

"I used the string and vacuum cleaner method."
Never heard of that method.

[Mikeflys]

"I used the string and vacuum cleaner method."
Never heard of that method.

Really? It's very easy, just cut a length of string about twice the length of your barrel. Tie a patch to one end, stick the other end in the breech and hold a running vacuum hose to the bore. It not worthy the string licky split down the barrel then you just pull the patch trough.

[Bwalton]

What made you decide to clean? only clean when you start to loose accuracy. It is going to take some pellets to get it back right maybe 20 maybe more.

[Mikeflys]

"I used the string and vacuum cleaner method."
Never heard of that method.

Really? It's very easy, just cut a length of string about twice the length of your barrel. Tie a patch to one end, stick the other end in the breech and hold a running vacuum hose to the bore. It not worthy the string licky split down the barrel then you just pull the patch trough.

Oh I forgot, this forum does not let you use the word that means to pull with a vacuum, it always replaces it with "not worthy". Not sure why because the word Suc* is not what I would consider a foul word. Especially used in context with a vacuum.

[Mikeflys]

I had just read several times that you need to clean your barrel after the 1st 500. I have put at least 200 downrange before taking the pictures today.

[BenjiHunter]

"I used the string and vacuum cleaner method."
Never heard of that method.

Really? It's very easy, just cut a length of string about twice the length of your barrel. Tie a patch to one end, stick the other end in the breech and hold a running vacuum hose to the bore. It not worthy the string licky split down the barrel then you just pull the patch trough.

Ok, I'll try that the next time.

[Bwalton]

Mike not true..... I go thru over 1000 shots and I shoot a lot, and do not clean until I notice  a loss in poi....But every gun is not the same. Oh and by the way I have never use a string, I have always used a brass brush and push rod followed by a fiber tip to push thru, just me though.

[Mikeflys]

I changed pellets and of course got a different result. I was originally shooting JSB Exact Jumbo Heavy's at 18.13 grams. I found the heaviest pellet I had on hand, H&N Sport Barracuda Match at 21.14 grams. Here is the result.

Not sure why it would shoot JSB well before cleaning and not after, but long story short the H&N's work great. I will play with other pellets later.

[Sfttailrdr46]

  Well maybe now that the rifle is broken and has you trained she decided to go on a diet

[Mikeflys]

Oh and by the way I have never use a string, I have always used a brass brush and push rod followed by a fiber tip to push thru, just me though.

That's funny, I don't know how many times I have read "Never use a brass brush on an air rifle". I have never completely believed that, it doesn't seem that the barrel would be softer than brass. I just don't have a fiberglass rod, so I use the string method.

[blackdiesel]

Mike not true..... I go thru over 1000 shots and I shoot a lot, and do not clean until I notice  a loss in poi....But every gun is not the same. Oh and by the way I have never use a string, I have always used a brass brush and push rod followed by a fiber tip to push thru, just me though.

I use a rod too, but nylon brush instead of brass.  I hardly ever clean my barrels.  If my groups open up I will clean them; I don't even keep a count between cleanings.

[William]

Oh and by the way I have never use a string, I have always used a brass brush and push rod followed by a fiber tip to push thru, just me though.

That's funny, I don't know how many times I have read "Never use a brass brush on an air rifle". I have never completely believed that, it doesn't seem that the barrel would be softer than brass. I just don't have a fiberglass rod, so I use the string method.

Brass brush will not hurt anything except maybe an O'ring if it is in the breech for sealing, you can use an aluminium rod if you want, it will not hurt the barrel either.  Only thing that will hurt it is generally a Steel cleaning rod or steel brush etc.

Oh, and that is some nice groups with the H & N 21 grainer's...

William

[mista meener]

I changed pellets and of course got a different result. I was originally shooting JSB Exact Jumbo Heavy's at 18.13 grams. I found the heaviest pellet I had on hand, H&N Sport Barracuda Match at 21.14 grams. Here is the result.

Not sure why it would shoot JSB well before cleaning and not after, but long story short the H&N's work great. I will play with other pellets later.

how far are you shooting? your rifle should shoot like that at 70 yds. I have 2 of those rifles and they shoot tiny groups at 50 yd  and at 85 yd inch and a half. try CPUM pellets both my rifles like them and do not bother cleaning until you see a change

[Mikeflys]

I changed pellets and of course got a different result. I was originally shooting JSB Exact Jumbo Heavy's at 18.13 grams. I found the heaviest pellet I had on hand, H&N Sport Barracuda Match at 21.14 grams. Here is the result.

Not sure why it would shoot JSB well before cleaning and not after, but long story short the H&N's work great. I will play with other pellets later.

how far are you shooting? your rifle should shoot like that at 70 yds. I have 2 of those rifles and they shoot tiny groups at 50 yd  and at 85 yd inch and a half. try CPUM pellets both my rifles like them and do not bother cleaning until you see a change

That was about 25 yards. Due to the 2 W's (work and weather)I have only had 2 opportunities to get out past 25 yards. But times they are a changing, I have just completed my night shift rotation. For the next 4 months I will have much more free time. Trips to the desert and the shooting range will be much more frequent. That is if the weather doesn't go south on me.

[mista meener]

Mike when you get used to the gun and stretch it legs out further you should see the groups get tighter. give the crosman ultra mags a try

[tt123]

I'd never heard of the 'string and vacuum cleaner method' before either. Sounds like it might be worth trying at some point though, as I've had a lot of trouble getting the string from my boresnake down a .177 barrel.

[Mikeflys]

I'd never heard of the 'string and vacuum cleaner method' before either. Sounds like it might be worth trying at some point though, as I've had a lot of trouble getting the string from my boresnake down a .177 barrel.

I found it here
http://www.gatewaytoairguns.org/GTA/index.php?topic=51555.msg500442#msg500442

[Methuselah]

Mike

Perhaps what you cleaned it with was dieseling?  Also, I see you are using a PCP (which I have zero experience with), but could pressure level in your tank have been atypical when you got the spread groupings?

I'd go back to the JSB's again later just in case it settles back down - hope you let us know when you get it straightened out Mike

I changed pellets and of course got a different result. I was originally shooting JSB Exact Jumbo Heavy's at 18.13 grams. I found the heaviest pellet I had on hand, H&N Sport Barracuda Match at 21.14 grams. Here is the result.
[Sorry, you are not allowed to post external links.]
Not sure why it would shoot JSB well before cleaning and not after, but long story short the H&N's work great. I will play with other pellets later.

how far are you shooting? your rifle should shoot like that at 70 yds. I have 2 of those rifles and they shoot tiny groups at 50 yd  and at 85 yd inch and a half. try CPUM pellets both my rifles like them and do not bother cleaning until you see a change

That was about 25 yards. Due to the 2 W's (work and weather)I have only had 2 opportunities to get out past 25 yards. But times they are a changing, I have just completed my night shift rotation. For the next 4 months I will have much more free time. Trips to the desert and the shooting range will be much more frequent. That is if the weather doesn't go south on me.

[Mikeflys]

I have done lots of experimenting since this happened. It turned out to be 2 issues. A combo of tank pressure and pellet weight. At full charge, 200 bar and down to 100 bar my gun will shoot 21gr pellets through the same hole. It just loves heavy pellets. From 200 bar to 150 bar it is the only thing I can shoot reliably, but from 150 bar down it will shoot 18gr pellets well. Under no circumstances will it shoot 14gr pellets. It just flings them around like crazy. So I have just started ordering only 21gr pellets and not fooling around with it any more. Besides the 21gr pellets make a real hearty thump when they hit a target, paper of fur!