Jump to content

Running in a new air rifle


Guest
 Share

Recommended Posts

Each one is diferent usualy about 1 or 2 tins but the most inportant thing is to clean properly with brass brush and rod followed with cloth or felt oiled pelets every 100 or so to remove any lead and other bits from it.after a few 100 you will get less and less till nearly none at all.

Though the quality of machining is far better than 20 years ago so it may not take anything like as much as it usto do i am expecting a new gun in afew weeks and intend to put 1000 through it in the air before i even put the scope on

Link to comment
Share on other sites

Each one is diferent usualy about 1 or 2 tins but the most inportant thing is to clean properly with brass brush and rod followed with cloth or felt oiled pelets every 100 or so to remove any lead and other bits from it.after a few 100 you will get less and less till nearly none at all.

Though the quality of machining is far better than 20 years ago so it may not take anything like as much as it usto do i am expecting a new gun in afew weeks and intend to put 1000 through it in the air before i even put the scope on

 

 

 

Most important thing? Sorry but I can't see how that's even necessary let alone important, PCP's maybe, the vapour left in the barrel might constitute a rust hazard but spring rifles don't benefit from such meticulous cleaning regime.

Link to comment
Share on other sites

at first you are removing bits of detritus left in the rifeling and that is what the first batch of pelets are for and to ware down any rough edges and it is inportant to get all the crud out as it gets worn away and not ground into the groves

as i said prob not as bad with the modern guns as was 40 years ago but better to do it .... in my oppinion

Link to comment
Share on other sites

Most important thing? Sorry but I can't see how that's even necessary let alone important, PCP's maybe, the vapour left in the barrel might constitute a rust hazard but spring rifles don't benefit from such meticulous cleaning regime.

 

 

PCP`s fire dry air .

 

If you have vapour in yours , get it serviced :lol: :lol: :lol:

Link to comment
Share on other sites

I polished the barrels on several of my rifles as soon as I got them. I have no before-and-after data but they sure shoot well.

 

I used bore mops with a couple of wraps of kitchen roll to make them a tighter fit, and a smear of diamond honing paste that used to be for polishing the ends of fibre-optic cables. This brings the barrels up a treat.

 

Also, have a look at the crown of the barrel, some factory jobs leave a lot to be desired.

 

The standard AirArms barrel crown was pretty horrible so I re-cut it as follows.

 

Standard crown

 

aacrown.jpg

 

First I set the barrel up in the lathe using a dial gauge on the outside of the barrel, to check that the bore was concentric with the outside I used a straight piece of ground steel rod wrpped with ptfe plumbing tape at both ends so that it was a tight fit in the bore with 2" sticking out of the front, it tuned out to be concentric so I machined the front face off the barrel to get rid of the AirArms crown

 

inlathe.jpg

 

Once the original crown was completely gone I started to cut the new one using a ball bearing quickly welded to a piece of spring steel and some diamond lapping compound. I'm sure that car valve grinding paste would work as well. I did most of it in the lathe on very slow speed whilst tilting the ball to different angles and frequently lifting the ball from the crown to allow the cutting paste to get back where it was needed.

 

ballandpaste.jpg

 

When the crown had expanded past the edge of the bore I removed the barrel from the lathe and did the rest by hand using a finer grade of paste and as random a motion as I could.

 

The crown soon took on a semi shiny finish, and although it is difficult to see in the photos, because of the distortion of the lens I used, the crown came out really well. It's 0.177 by the way.

 

newcrown.jpg

Link to comment
Share on other sites

In a springer you are lapping the piston to the cylinder bore and burning off any excess lubricant left over during manufacture-this can take anything from one to lord knows how many tins depending on quality of machining e.t.c.-the better quality guns tend to need little running in these days because of the advances in engineering practice (modern cars take less time to run in than 20 years ago).As for cleaning the bore I,personally,would not touch it with anything other than an occasional pull thru-any lead left in the bore is removed by the following shot unless a defect is present and "pitting" has left tiny pieces of lead to fill "holes"in the bore-this process of "leading" the barrel is desirable as it aids accuracy-poking a stiff brush down the tube could remove the lead and thus reduce the performance of your barrel.A pcp takes little running in as there is little in the way of metal to metal contact-more than one tin would be unusual.BTW catweazle-who cut the thread on that barrel cos its terrible-should have used a CNC.

Edited by bruno22rf
Link to comment
Share on other sites

At this stage the main object is not leading but for the abrasion of the pellets to remove any burs and little bits of badly machining bits that on the passage of the pellets, mark and damage the pellets and the removing of these to increase accuracy. pellets with bits knocked from skirt dont fly well Catweasle has done the same thing with grinding paste and probably quicker and better than it can be done with pellets, but he appeares to have or have access to equipment most dont have

Link to comment
Share on other sites

I polished the barrels on several of my rifles as soon as I got them. I have no before-and-after data but they sure shoot well.

 

I used bore mops with a couple of wraps of kitchen roll to make them a tighter fit, and a smear of diamond honing paste that used to be for polishing the ends of fibre-optic cables. This brings the barrels up a treat.

 

Also, have a look at the crown of the barrel, some factory jobs leave a lot to be desired.

 

The standard AirArms barrel crown was pretty horrible so I re-cut it as follows.

 

Standard crown

 

aacrown.jpg

 

First I set the barrel up in the lathe using a dial gauge on the outside of the barrel, to check that the bore was concentric with the outside I used a straight piece of ground steel rod wrpped with ptfe plumbing tape at both ends so that it was a tight fit in the bore with 2" sticking out of the front, it tuned out to be concentric so I machined the front face off the barrel to get rid of the AirArms crown

 

inlathe.jpg

 

Once the original crown was completely gone I started to cut the new one using a ball bearing quickly welded to a piece of spring steel and some diamond lapping compound. I'm sure that car valve grinding paste would work as well. I did most of it in the lathe on very slow speed whilst tilting the ball to different angles and frequently lifting the ball from the crown to allow the cutting paste to get back where it was needed.

 

ballandpaste.jpg

 

When the crown had expanded past the edge of the bore I removed the barrel from the lathe and did the rest by hand using a finer grade of paste and as random a motion as I could.

 

The crown soon took on a semi shiny finish, and although it is difficult to see in the photos, because of the distortion of the lens I used, the crown came out really well. It's 0.177 by the way.

 

newcrown.jpg

 

 

:good: Well handy to have the skills/equipment to do this! :yes::yes:

 

:good::good:

Link to comment
Share on other sites

Lapping a barrel is a rare necessity these days and it is foolish to assume that doing so will automatically increase the guns accuracy,it is also the domain of a highly skilled individual.We are talking about guns here that shoot over 40-50 yards and not a couple of kilometers so how much benefit is likely to be gained?-more likely to do more harm than good.Most barrel makers these days are very proficient(with the exception of the cheaper chinese makers who struggle to maintain consistent land depth)so time taken on your tube,unless it is obviously damaged,would probably be more worthwhile spent in other areas. :hmm:

Link to comment
Share on other sites

I agree Bruno

But look at the state that the gun of catweazel's left the c/o . and that is a area that is visable not hidden

I wont mention the make as everyone knows my oppinion of that 2nd rate company lol.but look at the thread on the end and the finish that ~Cat has had to finish again now if that was inspected and sent to it's new owner what will the inside of the bore look like so i think good idea to lightly hone it with paste . that wont do any harm , not like using a stone and then not need so many pellers putting through it

Link to comment
Share on other sites

Lapping a barrel is a rare necessity these days and it is foolish to assume that doing so will automatically increase the guns accuracy,it is also the domain of a highly skilled individual.We are talking about guns here that shoot over 40-50 yards and not a couple of kilometers so how much benefit is likely to be gained?-more likely to do more harm than good.Most barrel makers these days are very proficient(with the exception of the cheaper chinese makers who struggle to maintain consistent land depth)so time taken on your tube,unless it is obviously damaged,would probably be more worthwhile spent in other areas. :hmm:

 

Don't confuse polishing with lapping. Lapping would have involved using a sized lead slug to give a uniform, or even better, slightly tapering bore size. I just polished my barrels, to remove machining roughness. The barrels shoot very well, but as I wrote, I have no before-and-after data.

 

I view it as a process that the factory doesn't have the time to do.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...