i just got done doing a polish on the crown of one of my barrels.i turn it over to look at the leade-in ,its full of chatter marks across the bottom.im going to see if i can get a clear pic of it
what would you do with this barrel?
I use Craytex abrasives from http://www.cratex.com/ (http://www.cratex.com/) that mount on 1/8" shaft that fit my Dremel. You can do a gret job of polishing with them.
Carl
do you have a pic of the ones you use
i have to register to get any info
This is one of the kits I use.
http://www.amazon.com/CRATEX-RUBBERIZED-ASSORTMENT-123-PIECES/dp/B000HQG9B6/ref=sr_1_6?ie=UTF8&qid=1362021188&sr=8-6&keywords=cratex (http://www.amazon.com/CRATEX-RUBBERIZED-ASSORTMENT-123-PIECES/dp/B000HQG9B6/ref=sr_1_6?ie=UTF8&qid=1362021188&sr=8-6&keywords=cratex)
But you can look on Amazon and see lots of options for Craytex.
Carl
Here is another link:
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=Craytex (http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=Craytex)
Carl
And one more, http://www.amazon.com/Cratex-Point-Test-Part-No-778/dp/B0006NC4UA/ref=sr_1_13?ie=UTF8&qid=1362021188&sr=8-13&keywords=cratex (http://www.amazon.com/Cratex-Point-Test-Part-No-778/dp/B0006NC4UA/ref=sr_1_13?ie=UTF8&qid=1362021188&sr=8-13&keywords=cratex)
Carl
I use the same thing, they are fantastic and last a long time :-*
Damn... they are expensive for what I need to do. I need to do the same as Ed... my lead in on the 2300s is hanging up smaller lighter pellets... so I need to have a toothpick or something handy to straighten them up and finish pushing them in.
Don't want to spend that much for this one task. Any other options you can think of? Can I just get one Cratex maybe? If yes... which do you recommend?
You can buy a single bit. Do you have a Dremel tool?
Carl
Correct me if I'm wrong/out of date Carl...
I have a green one (course grit) and a red one (fine grit). One of each will be all you need.
Cool... Thanks guys!! Do have a dremel and was hoping to use that. Didn't realize I could buy just a couple... whew lol
Brent,
I don't have any cratex bits in my Dremel stuff. I must have used them up on something else before I got into modding airguns because I know that I did have some at one time. Here is what I did:
I took a 6" length of 3/8" hardwood dowel and sharpened it with a pencil sharpener. Then I made a small cone of 100-grit sandpaper with the grit on the inside the cone. Then I stuck the cone down inside the leade of the barrel I wanted to polish. Then used that to reshape the dowel to the correct angle because the pencil sharpener only got it close. When the dowel was correct, I used some 320 grit sandpaper to make another cone but put it on the sharpened end of the dowel and taped in place with the grit to the outside. I used that in a 3/8" electric drill to get the machine marks out of the leade and used progressively finer grits until I was using 600 grit wet-or-dry paper. Then I used a felt polishing cone in my Dremel with some jewelers rouge to finish the polishing. I was careful to not sand or polish any more than necessary because I didn't want the o-ring to stop sealing.
Good luck,
Good stuff... that is a good idea!! Thanks Jerry!!
Quote from: JEBert on February 28, 2013, 08:19:17 AM
Brent,
I don't have any cratex bits in my Dremel stuff. I must have used them up on something else before I got into modding airguns because I know that I did have some at one time. Here is what I did:
I took a 6" length of 3/8" hardwood dowel and sharpened it with a pencil sharpener. Then I made a small cone of 100-grit sandpaper with the grit on the inside the cone. Then I stuck the cone down inside the leade of the barrel I wanted to polish. Then used that to reshape the dowel to the correct angle because the pencil sharpener only got it close. When the dowel was correct, I used some 320 grit sandpaper to make another cone but put it on the sharpened end of the dowel and taped in place with the grit to the outside. I used that in a 3/8" electric drill to get the machine marks out of the leade and used progressively finer grits until I was using 600 grit wet-or-dry paper. Then I used a felt polishing cone in my Dremel with some jewelers rouge to finish the polishing. I was careful to not sand or polish any more than necessary because I didn't want the o-ring to stop sealing.
Good luck,
(http://www.pbase.com/lakebiker/image/148688931/original.jpg)
Quote from: chongman on February 28, 2013, 06:11:21 AM
Correct me if I'm wrong/out of date Carl...
I have a green one (course grit) and a red one (fine grit). One of each will be all you need.
That is the two flavors that I use 90% of the time. They do make others but you really only need the two.
Carl
thanks for the links!
i like that 700+pc kit that has everything i'll ever need
and you included a 26pc economical kit :-*
the question is whats the shelf life? ???
i would hate to get a large kit and have 90% of them dry up,get brittle or something
i polish more than just my air guns i just did a lot polishing on my ruger 10/22 and plan on getting a cz452 before the supply dries up i know that will need some polishing
thanks jebert for detailed tutorial :-*
Quote from: 1377x on February 28, 2013, 02:37:56 PM
thanks for the links!
i like that 700+pc kit that has everything i'll ever need
and you included a 26pc economical kit :-*
the question is whats the shelf life? ???
i would hate to get a large kit and have 90% of them dry up,get brittle or something
i polish more than just my air guns i just did a lot polishing on my ruger 10/22 and plan on getting a cz452 before the supply dries up i know that will need some polishing
thanks jebert for detailed tutorial :-*
Ed I've had one of the kits for years and not had any problem with them drying out.
And that big kit has got lots and lots and lots of pieces that I find myself using for all kinds of polishing jobs. The Craytex stuff works fabulous for buffing the trigger frame or barrel band or other pistol parts.
Carl
got a pic of the crown and leade in
looks like i need to work on the crown some more
now you can what this awful looking leade-in looks like
That leade looks like it was cut by someone with a nervous twitch using a hand drill with an out-of-round reamer. It's horrible!
Carl
Quote from: quickster47 on February 28, 2013, 03:46:44 PM
That leade looks like it was cut by someone with a nervous twitch using a hand drill with an out-of-round reamer. It's horrible!
Carl
YEAH!!!
the worst i have seen
could this aid in the shotgun pattern groups i am getting with this barrel?
I would not think the leade could do that because it is mostly used in seating the pellet. And then once seated the path down the barrel is pretty well defined with the rifling. I tend to think that the crown is more responsible for any exit pattern anomalies.
Are the pellets you are using a good snug fit?
Are you getting an occasional flyer or a consistent number of flyers?
Carl
Shelf Life?
The few polishing points I have are about 20 years old and still good to go ;)
that is a nasty leade ed ,agree with carl that bad crowns are more responsible for bad grouping but such a shoddy leade could easily damage the pellet as its pushed into the bore
ped
i was thinking the pellets might be getting damaged by the funky leade
i'll report back on the condition of the barrel after i clean up the chatter marks
Quote from: quickster47 on February 28, 2013, 03:57:17 PM
I would not think the leade could do that because it is mostly used in seating the pellet. And then once seated the path down the barrel is pretty well defined with the rifling. I tend to think that the crown is more responsible for any exit pattern anomalies.
Are the pellets you are using a good snug fit?
Are you getting an occasional flyer or a consistent number of flyers?
Carl
you know i havent noticed how the pellets fit.thats something i will check
i know the pellet thats in the muzzle now wasnt easy to get in there its pretty tight.
forgot what was making the pellets fly everywhere,i remember now, that is getting fixed too ;)
the question is
what is the benefit of cleaning up the leade-in ?
Mainly it makes certain that the pellet is not damaged during loading and that the pellet is correctly seated in the barrel after the air port and into the rifling.
Carl
ok
those marks are sharp enough to damage a pellet
hopefully i can remove them without removing to much material from the barrel
any suggestions?
Dremel makes rubber polishing points - #462 & #463 - for those of us that do not need a lifetime supply of Craytex bits. I have a few on order to try.
Terminology catching up with me again :)....I call it a forcing cone. ??? Does look pretty rough.
Anyhooo....if the head of the pellet catches on the transfer port (burrs or sharp edges), it can be damaged resulting in an out of balance condition (spinning projectile). Can lead to cork screw patterns of flight and more.
Will suggest you re-mount the barrel to the receiver, seat a pellet using the bolt. Then remove the barrel, check the position of the pellet relative to the transfer port. Using a wood dowel, push the pellet back out the breech end of the barrel.
Inspect pellet for damage...if you find any, smooth over the transfer port edges in the chamber.
Otherwise...Is this mag fed or single shot? Do other mags make a difference?
Crown looks nice Ed...well done! :-*
Al
+1 to Gippeto... forcing cone in a powder burner.
Use a small brass welding rod .125" or wood dowel to push the pellet thru the barrel Ed, look at the pellet under 2x or better mag with good light after it comes out, you will be surprised at what you see! :-*
Quote from: Gippeto on March 01, 2013, 04:38:36 PM
Terminology catching up with me again :)....I call it a forcing cone. ??? Does look pretty rough.
Anyhooo....if the head of the pellet catches on the transfer port (burrs or sharp edges), it can be damaged resulting in an out of balance condition (spinning projectile). Can lead to cork screw patterns of flight and more.
Will suggest you re-mount the barrel to the receiver, seat a pellet using the bolt. Then remove the barrel, check the position of the pellet relative to the transfer port. Using a wood dowel, push the pellet back out the breech end of the barrel.
Inspect pellet for damage...if you find any, smooth over the transfer port edges in the chamber.
Otherwise...Is this mag fed or single shot? Do other mags make a difference?
Crown looks nice Ed...well done! :-*
Al
the gun is single shot no plans on a magazine
i am afraid of over doing something and next the bolt o-ring wont seal
Don't remember if this was mentioned anywhere in your previous posts but are the pellets difficult to load? Are wadcutters the worst behaved if you have trouble loading any pellets?
I know this was discussed in some thread that all pellets appear to load really well with the Crosman OEM plastic breech but soon as a steel breech is installed loading pellets can be a real PITA.
What breech do you have on this gun?
Carl
Ed, there's a small dim light coming on here...maybe...or maybe not. ;)
What is that barrel off of? What caliber?
And what are you using for a breech and bolt?
Could be lack of caffeine...or morning inspiration...only the shadow knows. ;D
Al
Quote from: Gippeto on March 03, 2013, 04:29:24 PM
Ed, there's a small dim light coming on here...maybe...or maybe not. ;)
What is that barrel off of? What caliber?
And what are you using for a breech and bolt?
Could be lack of caffeine...or morning inspiration...only the shadow knows. ;D
Al
the barrel is off my 2300hpa gun it is .22
i am using a crosman steel breech with a mellonair extended probe bolt. since i found out the mellon bolt in .177 performed better than my brass bolt ,i am going to put a brass extended probe bolt in this gin and move the mellon bolt to my stainless 2260pcp
i guess i could have shoprtened this to say it has a mellonair bolt in it now but will be using a brass extended bolt when i put it back together
the brass bolts came from the same maker from the looks of them
Maybe it's looking at the pics on my phone instead of a computer screen, but it looks like the breech end of the barrel has no significant taper (forcing cone) and has an o-ring installed....like the .25 Marauder barrels I've had.
Just my phone?
Al
Quote from: Gippeto on March 03, 2013, 04:54:59 PM
Maybe it's looking at the pics on my phone instead of a computer screen, but it looks like the breech end of the barrel has no significant taper (forcing cone) and has an o-ring installed....like the .25 Marauder barrels I've had.
Just my phone?
Al
you know it has a very small forcing cone
hopefully these pis can show it better
Would a soft Pencil eraser and some Valve Grinding paste,toothpaste ot Simichrome Polish do any good here for either Operation?
hth
Mario
i for one have no idea
when gippeto brought up the point of the forcing cone i had to listen.i see a very distinct groove in the barrel and if i am hearing gippeto right it sounds to me like this might be a marauder barrel reworked to remove the end of the chamber so a bolt o-ring would seal the chamber instead of a barrel o-ring and a bolt with no o-ring. there is a slight cone though enough for the bolt o-ring to seal just barely enough the face of the bolt is right at the edge of the transfer port.this is with a mellon bolt a stock bolt the face of it goes into the transfer port
Here are three pictures of a Crosman .177 barrel I just removed from one of my Crosmaniac guns and replace with a Lothar Walther barrel. Nothing has been done to the leade on this barrel it is just as it came from the factory.
It is hard to get a really good photo of how the inside looks but I think it might be different from yours Ed. Might have to get out my Nikon and put the macro lens on it and try it that way.
Carl
quickster do you have ant .22 barrels laying around?
the barrel in question is a .22 dont know how much of a difference thats going to make ???
I have several .22 barrels. I'll go get one and take some pictures of it.Carl
thanks!
this has peaked my interest
the barrel is off a parts gun so its origins are not known to me or the seller
Okay here is the first set of two sets of three pictures taken of two different Crosman .22 cal barrels. Neither one has had anything done to the leade end.
When you zoom in on these things they are horrible looking and really hurt your eyes. :-[
I'm also not sure what is the best way to photograph them. Open to suggestions.
Carl
Here is the second set of two sets of three pictures taken of two different Crosman .22 cal barrels. Neither one has had anything done to the leade end.
I'm also not sure what is the best way to photograph them. Open to suggestions.
Carl
Both barrels came from guns with Crosman long steel breechs and neither one of them had any problems loading pellets if I remember correctly.
Carl
Any of you guys familiar with a Conical cutter, some call them a tapered end mill? They come in any degree taper. I suspect a nice leade can be achieved with one of these once the correct angle is established with a little math. Why doesn't someone do some measuring of the length and max diameter, figure the angle and machine it with a conical cutter in the lathe. Or, turn the compound on the lathe to the proper angle and use a small boring bar?
Quote from: mr007s on March 05, 2013, 02:54:08 AM
Any of you guys familiar with a Conical cutter, some call them a tapered end mill? They come in any degree taper. I suspect a nice leade can be achieved with one of these once the correct angle is established with a little math. Why doesn't someone do some measuring of the length and max diameter, figure the angle and machine it with a conical cutter in the lathe. Or, turn the compound on the lathe to the proper angle and use a small boring bar?
I am familiar with the conical cutter but have never used one. I also just happened to visit a web site yesterday that was discussing conical cutters.
Going to need to do some digging and research on the best way to do the leade for Cormans and then see about cutting a new one. At least I have a couple of barrels to play around with and can screw up if need be.
Thanks 007...
Carl
The pics looked fine/ good Carl. I could make out the machining marks.
What struck me, is that neither looked that great. It seems that close enough works for most pellets OK. Can't imagine what mine is going to look like when I finally get it out of the 2300s. Hell or high water... mine does not like small wad cutters (like Daisy) when loading them. They always catch bottom front... and I have to use a plastic pick to bring the skirt back down straight and help them in. Even adding a drop of pelletgunoil there... helps very little.
Thanks again... that was educational to see/ know!
I gathered up a few Conical cutters today and snapped a pic for posting here. This will clarify what I am referring to. In the photo from the left are a 5, 10, 15, 20, 30, and 45 degree cutter. We have them in 1, 3, 7, 12, 25 degree but they must be stashed in one of the guys tool box so they are not pictured.
(http://i46.tinypic.com/33jr2pl.jpg)
I had a spare .22 cal barrel in my stash and did some measuring to determine a starting point as to what Crosman had cut it. My limited math skill came up with 19.58 degrees for this barrel. I have not determined if a .177 will be the same for the lead but I suspect it will be near that.
After chucking the barrel up close in the lathe and placing the 20 degree cutter in the tail stock I gently touched off on the barrel end. I had painted the end with Dykem to help me see when things made contact. Since I only wanted to smooth the factory finish I turned the chuck by hand only, after freeing up the brake. It cleaned up nice and I only did a final finish with a piece of Scotchbrite.
Took it all home and fitted the barrel in a spare breech with a stock probe. Using a CPHP I used the probe to set the pellet. I then pulled the barrel out and could see half the pellet blocking the TP opening.I then mounted an extended probe and repeated the previous steps. The pellet and complete skirt were well past the TP. I took the probe from the breech and eased it into the pellet by hand to get a feel for how much contact was being applied to the probe O-Ring. It felt very snug and I imagine no air would blow back by it.
So, I conclude a 20 degree taper works for a .22 cal barrel with the large end of the leade to measure in the .275-.280" range. This allows the lead to be app. .08" long. If you were to use the 15 degree with a .275 opening at the rear the length of the leade would increase to .118 or 3 mm. I believe that would be acceptable also but I will need to round up another barrel an repeat this test to say for sure.
Hope this helps clear some of the mystery as to the barrel machining. I really wish CM would revel his operation on this subject.
Below is a photo of today's finished experiment.
(http://i46.tinypic.com/orqhx5.jpg)
Wow!!
Very Cool!!!
Thanks so much for doing all that! Really good information to know! Nice
Mr007 where would be the best place to get a 15 and 20 degree conical cutter?
I have several barrels that I would like to play around with and see if I can improve them.
Thanks,
arl
Would a Bullet shaped Rotary File,work here?
Mario
Quote from: Pumpmeister on March 06, 2013, 12:37:59 AM
Would a Bullet shaped Rotary File,work here?
Mario
Don't think it would because you would end up taking off way more than you intended because of the shape of the tool.
Carl
I see.......Hmmmm. :-[ Okay Do Most Harware stores or Machinists supply shops have tha 20 deg. Tool?
Mario
With some careful grinding and sharpening, a 3/8 split point drill bit could be reshaped to 20 degrees and used in place of a 20 degree Con.. We have to make our own tools in this fashion occasionally for odd cuts and such. This approach would not leave as nice a finish as the Con simple because the Con is multi fluted.
Carl I will look tomorrow for our supplier, it is either McMaster Carr or MSC
edit to change MSG to MSC
Quote from: Pumpmeister on March 06, 2013, 12:48:42 AM
I see.......Hmmmm. :-[ Okay Do Most Hardware stores or Machinists supply shops have the 20 deg. Tool?
Mario
Doubtful they can be found at any hardware. The two businesses posted above carry them. Even though they are called Conical cutters do your search using "tapered end mill"
very nice
there is a thread on airgunhome that covers chamber making but your method is much easier unless you have to make the tool
maybe gippeto will chime in since he makes his own leade-in/chamber
Thank you Ray,
I want to try resharpening a drill to the correct angle but didn't know what angle. I cut a leade in a .22 caliber barrel with a tapered reamer and am using it on a gun but the angle is too shallow. I stopped when the o-ring is still sealing and then drilled for the transfer port using the steel breech to figure that location. The extended probe pushes the pellet past the transfer port but the pellet is a little loose in the barrel. I'll cut the barrel off just ahead of the transfer port, loosing 1/2" of length, and try again now that I know the angle. I'm pretty good at sharpening drill bits but it will be fun trying to sharpen one at that angle as I've never done that before.
I'm not a trained machinist, so just to be clear, it's 20 degrees from the centerline of the bit, not 20 degrees included angle, correct?
Cheers,
Quotemaybe gippeto will chime in since he makes his own leade-in/chamber
I use a small HSS boring bar @ 11 degrees for forcing cones and the bolts. Polish to 1000 grit with cutting oil. Have had excellent results in .22...I don't play with Crosmans in .177 much at all.
My .25" barrels do not have any forcing cone as IMO they don't need one...the pellet rides in the trough of the receiver and gets pushed through the o-ring. The edge between the chamber and the o-ring is relieved and polished to eliminate any hang ups there.
Have used 11 degrees for the forcing cones on a couple 1077's and a Night Stalker as well...big improvement in feeding.
11 degrees is the "standard" (IIRC) for the forcing cone on pb revolvers.
Al
Quote from: JEBert on March 06, 2013, 06:50:45 AM
Thank you Ray,
I want to try resharpening a drill to the correct angle but didn't know what angle. I cut a leade in a .22 caliber barrel with a tapered reamer and am using it on a gun but the angle is too shallow. I stopped when the o-ring is still sealing and then drilled for the transfer port using the steel breech to figure that location. The extended probe pushes the pellet past the transfer port but the pellet is a little loose in the barrel. I'll cut the barrel off just ahead of the transfer port, loosing 1/2" of length, and try again now that I know the angle. I'm pretty good at sharpening drill bits but it will be fun trying to sharpen one at that angle as I've never done that before.
I'm not a trained machinist, so just to be clear, it's 20 degrees from the centerline of the bit, not 20 degrees included angle, correct?
Cheers,
Bert, if you look at the photo on reply 47 the 20 degree cutter is 4th from the left. That will give you an idea as to how sharp the angle should be.
After I had measured and did the math yesterday I took a stick of dental wax, heated it and stuck it in the barrel. After it cooled I removed it and took it to the comparator to double check my figures. The total angle was right at 40 degrees so the 20 degree is per side.
Looked today at prices and mcMaster Carr has one that should do a good job for app. 25 and change.
MSC was considerable more. I have not checked on Amazon or E-Bay which may be an option.
Thanks Ray,
I am considering recycling all of the front of the barrels I have cut off. I have about four pieces long enough to make more barrels out of.
Cheers,
Quote from: mr007s on March 06, 2013, 11:37:02 PM
Bert, if you look at the photo on reply 47 the 20 degree cutter is 4th from the left. That will give you an idea as to how sharp the angle should be.
Is that the tool you used to do your test cutting?
Carl
Quote from: quickster47 on March 07, 2013, 03:33:32 AM
Is that the tool you used to do your test cutting?
Carl
Yes Sir, it is the same one.
Quote from: mr007s on March 07, 2013, 11:36:28 PM
Yes Sir, it is the same one.
Thanks, and I'm going to order one of those tonight. Will be needing it to work on the .25 caliber barrel I got to go on my 2240 which will then become a 2540.
Carl