I am having an issue with accuracy at 10 yds with my modified 1377 in .22 cal. I was able to hold down same hole groups with my stock .177 barrel self recrowned and lead in polished. Yesterday I received my order for a .22 flow thru bolt, sold pivot pin, and 23.5", recess target crowned 2260 barrel. I inspected the barrel with a Q-tip and there were burrs on the inside edge of the crown and the second inner diameter isn't centeredto the O.D.. The inside edge isn't 11 degree as it should be, but flat. And the finishing looks like it was only machined. There is no sign of anything higher than a 200 grit on this crown. I have included a picture of the crown. I locked the barrel in good with three set screws on my free floated highly modded 1377 carbine and shot some Crosman HP couldn't get them to group in any kind of pattern. Picture also included. Next I tried some destroyers, again erratic. Then I tried some Crosman pointed, again horrible. I am frustrated because I have been waiting so long and now this is just disappointing. I have a TKO 6.5 and when it is on it shoots even worse. Anyone have their TKO mess up acccuracy? I mean this is only 10 yds...
I am not going to say who did this job, but i will say I am convinced this is not his/her best work. My question to everyone is,
1. Have you ever had a bad crown job by a custom supplier?
2. Who does good crown jobs?
3. What type of crown is best for 2260 barrel?
4. Have any of you had a problem with a 2260 barrel?
5. What pellets have y'all had luck with in a 2260 barrel for long range accuracy?
I am having an issue with accuracy at 10 yds with my modified 1377 in .22 cal. I was able to hold down same hole groups with my stock .177 barrel self recrowned and lead in polished. Yesterday I received my order for a .22 flow thru bolt, sold pivot pin, and 23.5", recess target crowned 2260 barrel. I inspected the barrel with a Q-tip and there were burrs on the inside edge of the crown and the second inner diameter isn't centeredto the O.D.. The inside edge isn't 11 degree as it should be, but flat. And the finishing looks like it was only machined. There is no sign of anything higher than a 200 grit on this crown. I have included a picture of the crown. I locked the barrel in good with three set screws on my free floated highly modded 1377 carbine and shot some Crosman HP couldn't get them to group in any kind of pattern. Picture also included. Next I tried some destroyers, again erratic. Then I tried some Crosman pointed, again horrible. I am frustrated because I have been waiting so long and now this is just disappointing. I have a TKO 6.5 and when it is on it shoots even worse. Anyone have their TKO mess up acccuracy? I mean this is only 10 yds...
I am not going to say who did this job, but i will say I am convinced this is not his/her best work. My question to everyone is,
1. Have you ever had a bad crown job by a custom supplier?
2. Who does good crown jobs?
3. What type of crown is best for 2260 barrel?
4. Have any of you had a problem with a 2260 barrel?
5. What pellets have y'all had luck with in a 2260 barrel for long range accuracy?
Maybe they forgot to lap the inside edge of the crown? ???
well i dont see any target pics!???
1. yes
2.if you are looking for a target crown you can try to convince muzzlemack aka yourdaddyjoe aka hpa sports to do one for you he had the best target crowns i have seen.mac-1 is another that comes to mind.i get my barrels cut and crowned locally but he is so busy he isnt taking any work like that.air gun repairs only now and sales
3. the crown that has no flaws! im serious.a concentrically square cut barrel needs no crown to be accurate all a crown does is protects the muzzle
4. there has been many reports of bad barrels 2260 and others crosman barrels are a crap shoot.lucky for me i get to inspect all my barrels before i buy.just got a 2260 barrel on saturday picked through 8 found the one i liked best
5.try a jsb pellet they seem to be the most consistent when it comes to a good pellet out of a crosman or the boxed cp's.there is a certain lot you want if you get cp's hopefully someone will chime in with the lot number
why are you using a breech band? ???
1377x your right but you forgot to mention a concentrically,square cut crown "without internal burrs" Although I do not believe the crown to be concentrically cut. :( I should have just asked for a normal rounded crown and I would be much happier. So what did you/ supplier do about your bad crown job, 1377x?
I really need to order some JSBs, I wish I knew someone here that sold them so I didn't have to pay shipping. I mean I could buy a whole new tin for what pyramid air wants to ship one tin. I think they do that to get you to buy 3 tins at once! So what weight seems to work for people in JSB exact? I was thinking of the 16grs since this isn't a PCP.
How much do muzzle mack and Mack 1 charge for a barrel and crown and maybe a lead in polish? might need to just PM them... :P
Also, 1377 I am using a breech band because I am free floating the 23.5 incher. I am trying to attain maximum accuracy and FPE for fall and spring squirrel hunting. the breech screw is just wimpy and with the rear screw locked down tight the barrel raises up because of the wimpy breech screw. The breech band is ugly but it helps seal my valve perfectly and it keeps my barrel parallel with the main tube. Finally, I am a poor college kid and I can't afford a metal barrel band which may or may not be as accurate as a full floated barrel. I saw the Uber pumper had it and I copied except I mounted it straight to the main tube for a more flush look.
I'll post groups tomorrow if I get a chance to shoot. sorry
hey dont get down on yourself for wanting something you like.its not your fault the supplier/vendor didnt come through.pm me the name i have a clue as to who it is :-X
well all the barrels i have had cut and crowned were done professionally and never a bad job done.the 2260 barrel i just got i chose because it was the best one out of eight cosmetically had the cleanest bore and a decent looking concentric muzzle/crown
when i was using a .22 14.5" barrel on my 1377 my go to pellets are jsb stratton and now predator poly mag both 16gr.look up www.straightshooters.com (http://www.straightshooters.com) they sell a sampler pack not cheap but worth it when looking for the right pellet.thats another shop close to me 45 minutes away i have a friend who drives by there every weekend when i get a chance im going to go up there just to see what its about.maybe get some supplies but i get just about everything i need 10 minutes from me.
you can try going to crosmans site and look for a service station in your area.maybe you have one near by that you dont know about
as far as getting a nice target crown done muzzlemack aka yourdaddyjoe aka hpa sports had the best looking target crowns i have seen.he used to do it as a service but that was when he was muzzlemack.i would contact him and ask politely if he would be willing to make you up a target crowned barrel. the worst he do is say no and closed mouths dont get fed ;).it wont be cheap expect to pay $40 i think thats what his old price was.you can also try Lloyd Sikes www.airgunlab.com (http://www.airgunlab.com) he is a master modder expect a long turnaround as he is one of the most sought after vendors now.probably wont be as long as mellons wait, he has a lot of work going his way and actually my first choice for custom work.i lucked out and caught him at the right time with my Oogie Boogie build.the turnaround time was short.i think mac-1 is about $40 also he does an accuracy prep on the barrels.most of the time he does good work,heard a complaint or two from unsatisfied customers but no personal experience, again a long turnaround time.workinmanva is also equiped to do the job,he's going to be doing some barrel work for me soon.i havent used any of his barrels yet but he does supply what i need.http://www.workinmanshootingaccessories.com/ (http://www.workinmanshootingaccessories.com/)
ask him i dont know what style of crown he does but its worth a shot ;) pun intended :P ;D
your in college thats important and a start, you wont be broke for to long after you graduate :-* get that education.your not the only one to use the high tech sightly breech band about 2 years ago i used the same one
not because my barrel pointed up, that doesnt hurt anything,imo. i made a 88yd shot with my one set screw breech. the breech band was for sealing and to secure the breech to the tube, my front breech screw hole was stripped :-[
see my high $$ red dot ;) ;D it helped me make that 88yd shot. call it luck if you want but that barrel was the most accurate barrel i had and it was stock. just sold it a couple months ago after 4 years,1000's upon 1000's of pellets and many transfers to different guns
(http://i613.photobucket.com/albums/tt211/edf73/PA180344-1.jpg)
i feel bad for people everytime i see shotty work and the money used for it was hard earned and/or long saved.i dont have money trees and im not droid(no offense good buddy) so i research all my purchases and ask a lot of questions before someone gets my funds.it litterally pays to thoroughly research and ask the right questions so think about what you are going to ask and prioritize the needed details
there are many forums and peope talk. its easy to find out who to avoid and who to deal with.i saved $60 by researching 13ci hpa tanks and modding the regulator myself.out of the $60 saved, i put $30 back into hpa by building a regulator reader.now i can keep modding it and recording what every mod does instead of spending another $75 on another reg. i just spend $20 for parts and get the same thing cheaper. the next $70 tank i mod, the $60 saved is all mine to do with as i please :)
hope everything works out for you!! (http://www.freesmileys.org/smileys/smiley-signs003.gif) and keep your head up(http://serve.mysmiley.net/happy/happy0025.gif)
That crown does look kind of rough. It doesn't look like a Mellon crown and I've had good experience with his work. Never had a muzzlemack barrel but judging by the workmanship on his brakes, I'd say its probably outstanding.
1377x Thanks for the encouragement! But i would rather not spread his name around for his sake. I just hope he emails me back and makes it right. I have been waiting to squirrel hunt with my pellet gun since Sept. 15th... I wouldn't take a shot at one with such horrible accuracy at 10 yds. I need at least quarter inch groups at 10yds thats minimum. Nice PCP by the way! I looked at the unsafe gadget but I saw Rick Eutsler of airgun web was only getting abo 550 fps with 14.3s. So I have strayed away from that route. Also the pump is just as expensive as the gun if not more.
That crown does indeed look rough...and very poorly done IMSHO.
A recessed flat crown is my favorite for simplicity of setup and excellent results.
(http://i245.photobucket.com/albums/gg76/gippeto_album/20120710_122439.jpg)
Aside...Terminology is an interesting thing...I consider the "crown" to be the actual point at which the bullet/pellet leaves the barrel...the rest is just "dressing" ie...11 degree, recessed, double step recessed...and so on. Setting the crown "back" with any of these methods is intended to protect the crown from damage.
Al
Gippeto, Those crowns look nice. You're right about what you consider to be the crown. I just use the whole design to describe it. This is what I had in mind of seeing when I go my barrel.
Certainly not what you recieved. :(
Hope the fellow you dealt with makes it right for you.
Al
i was under the impression that the crown protected the muzzle
thats the way the videos by midway and others made it sound to me
Eh...it's terminology, which is a "learned" thing. In the end, it doesn't really matter if everyone calls it something different...as long as when they're talking to someone else, that someone else knows what they mean.
Muzzle to "me" is the whole end of the barrel. ;)
You'll also catch me referring to a Crosman"breech" as a "receiver"....I KNOW that with airguns (Crosman products at any rate), the common terminology is "breech"....with PB's, it's receiver, with cannon, it's again "breech". Each is correct...depending upon whom you're talking to.
Al
the crown is the last circumference of metal that the projectile passes through before dynamic projectile motion begins. If the crown isn't perfectly square with respect to the bore line, the projectile will experience drag on the area of barrel still in contact with the rear of the projectile. This drag force induces a y component moment with respect to its z axis along the projectile's center of inertia. If the projectile is also subject to tangential forces ( i.e. rifling) along its diameter, the net effect of the moments and forces creates a wobbly un-stabilized projectile .
i hear you
i did not recall correctly what i saw either
here is the video i was referring to
[youtube]https://www.youtube.com/watch?v=gsg-Yt6t-HM#ws]Gunsmithing - The Importance of the Muzzle Crown for Accuracy[/url]
Great video 1377x! That guy is so freaking happy! lol I bet he loves airguns!
Here's a very crude way to do it. I don't believe I will ever do it this way if I have to.
[youtube]https://www.youtube.com/watch?v=OorpZlG28fI#ws]Gunsmithing - How to Re-Crown the Muzzle of a Winchester Model 60 By Larry Potterfield of MidwayUSA[/url]
that wheeler fixture is no longer available or i would do it that way this might be a good alternative for the wheeler fixture though
these are hardened so filing wont damage them they need to remain squared to be effective
http://www.ebay.com/itm/MATCHED-V-BLOCK-HARDENED-W-CLAMPS-MACHINIST-TOOLMAKER-/370686015312?pt=BI_Tool_Work_Holding&hash=item564e9bb750 (http://www.ebay.com/itm/MATCHED-V-BLOCK-HARDENED-W-CLAMPS-MACHINIST-TOOLMAKER-/370686015312?pt=BI_Tool_Work_Holding&hash=item564e9bb750)
"Best" group at 10yds with .22 Crosman HPs!
Quote from: CajunHoss240 on November 14, 2012, 06:56:33 AM
"Best" group at 10yds with .22 Crosman HPs!
Off-hand or rested?
prone supported
what other pellets have you tried?
that might make a difference might not
wont hurt to try
I have tried Crosman HPs, Destroyers, and pointed. the pointed are doing better. I need to order some pellets from PA. Any suggestions for 2060 barrel"
Also I read that if you cut a barrel with a pipe cutter it forms a choked barrel by way of straining the outer circumference of the barrel to cut it. Also I heard this increased accuracy and decreased picky barrels. Any thoughts? Suggestions? Experience?
first i have heard that!
i know a pipe cutter leaves a lip inside the barrel which isnt a good thing another thing is the barrel wont be square close but not quite there.
i dont think i would use one
Did you push any pellets through that barrel? Were they tight...loose....tight THEN loose....loose then tight? Any tight spots mid barrel?
Did any seem to snag at the muzzle?
Al
there is a lot more to assessing a bad barrel,barrel crown rework than i knew
It would be easier if they all shot well wouldn't it. ;)
Barrels as I see them...feel free to disagree. :)
Think of a choked barrel. The choke is essentially a tight spot at the muzzle end of the barrel. The pellet gets swaged down a little, and is forced to be centered in the bore (and straight) when it leaves the muzzle.
If we have a tight spot at the breech end (or mid barrel) the pellet gets swaged down there. As the bore loosens up, the pellet can skew in the bore (ever so slightly) and leave the muzzle not centered and not entirely straight. Because it's spinning, it's now acting like a wheel out of balance...it'll be wobbling around, possibly corkscrewing it's way to target. This isn't going to help accuracy.
Al
thats something i havent given much thought
i just bought a new barrel recently a 2260 barrel tomorrow i will clean it wont be able to try it out until i tank my bottle filled i left it half open and closed when i left in a hurry last week when i went home and the air leaked out the asa adapter.im just going to use the jds adapter as it was designed then thay problem will be eliminated
Same here, very interesting point. I did have a .177 barrel that was very picky but a really good cleaning (something I don't always do) fixed the problem. And I haven't cleaned it since. Go figure ???
1377x, I know! Everyone focuses on external ballistics when the cause is internal ballistics. Gippeto I'm gonna do that tomorrow I know some of the pellets fit snug in the breech. Maybe they are being swagged there and not later in the barrel length. I need to pick up some fine sandpaper to tomorrow and polish the lead in. Maybe that'l improve accuracy.
On a happier note, me and a friend who NEVER shot a pellet gun in his life, shot and cleaned two squirrels at 20 and 25 yds this afternoon- about 3:45pm. I had my rifle pumped 12 times. I'm guessing I'm getting at least 600fps from the super light valve spring, FT, long barrel, and sealed transfer port.
I shot mine right where I wanted to with a Crosman HP, just behind and below his ear broadside. My friend shot his squirrel from the back and the pellet traveled through the body up to its chest. Both squirrels died quickly and didn't run but for a second before dying. Got em' marinading in the fridge!
My friend's pellet was lodged in the chest. Mine was a clean pass through. Poor guy was distraught he made a sub par shot, but i told him it was better than a wounded squirrel running around.
yeah a lot of people beat themselves down over a blown shot but like you said even so it was still a quick kill from a guy who has never shot a pellet gun in his life
hope your barrel gets sorted soon
Well, I pushed the pellets have all down the barrel multiple times and of course I figured out my barrel is tighter at the 1st 3.5- 4 inches then it opens up and is generally same pressure pushing until the crown. So this maybe a problem. I did the same with my stock 1377 barrel and it was the same. I was thinking that my set screws could be choking the barrel so I took the barrel off and the same was true. I then though well maybe I can choke the end of my stock 1377 barrel by putting it into my steel breech and locking it down. I did this at 90 degree increments and still nothing. So I have come to the conclusion that crosman must chuck the barrels up in a lathe at the breech end and if they do the same at the other end its not tightened down with as much pressure. So essentially they are reverse choking their barrels. Why couldn't they just choke the ends? If I had a 4 prong chuck I would. I have heard about the pipe cutter trick but it seems that isn't a very good method. What do you guys do to choke your barrel for cheap?
Also update, I have sent my 2260 barrel to the merchant for his " normal" crown. Hopefully, it is done well and accuracy increases. I might still have to find a way to choke the barrel though seeing as a LW barrel is $100.
i've been thinking about asking the guy who makes up hydraulic hoses for me, if he could do the end of a barrel to put a choke in with his crimping machine
ped
Rotary Swaging machines are what LW and other "good" barrel makers use, barrel is cold worked about 100 deg F, no more.
Uneven clamping or makeshift swaging obtains dubious results.
That's unfortunate.
If you had the ability to chamber the barrel and drill the transfer port, I would have suggested swapping the barrel end for end...result would be a nice choked barrel. :)
Good luck with it at any rate.
@BDS....Always wondered how the manufacturers choked barrels...interesting stuff. :-*
Al
intresting way of doing it the hydraulic hose crimper has only about 10 contact points so might not be a good idea to go down this route
the only reason i was looking into doing this is because i was hoping to cut a .20 barrel in half so i could build two guns with one barrel blank (we're careful with our money in yorkshire) and due to limited choice of pellets was hoping to choke the unchoked half to avoid it being pellet picky
i dropped lucky when i did this with the .25 as the unchoked half loves h&n ftt's,i'm going to just cut and see what the results are when i get around to getting a barrel
ped
First of all, Thank you all for helping me troubleshoot and for all the helpful suggestions!
Today, I stopped off at Bass Pro Shops in Denham Springs, LA to look for a high quality domed pellet. Being that it was the Saturday after Thanksgiving, the airgun and airsoft isle was swamped with mothers trying to find their son/ daughters a suitable airgun. I ran into this poor woman who was trying to buy a Gamo whisper recon in .177 for her 8 yr old step son so that he could shoot the possum and raccoon that forage their trash. Needless to say, I talked her out of that purchase. I pointed her to pyramidair.com, amazon, and walmart to find a suitable .22 cal rifle capable of taking the vermin for around $100. Poor lady lost her husband and was pushing her mother in a wheel chair to find a suitable airgun. I was extremely happy to help her make her stepson happy this Christmas. I explained how a spring airgun worked, gave her a list of high quality domed pellet manufactures and weights, and demonstrated to her how her stepson must hold and shoot a spring gun for accuracy and precision. She was very grateful and told me thank you about 12 times.
Getting back to the point of my post, I intended to find a pellet that would produce same hole accuracy out of my 1377-->1322 conversion rifle with 23.5" 2260 barrel and tko muzzle brake. I chose RWS Super Dome .22 14.5gr. Well I just got back and shot a group and WOW!!!! I have never seen such accuracy! Every pellet is PERFECT! The heads are almost polishes and the body and skirt are free of any seems. The rear is flat and round with no dents or shavings! I am impressed with German pellet manufacturing to say the least! I assume they are 6 sigma as far as QC goes.
The down side to my purchase is that I paid an ultra premium $14.99 for 250. It was an impulse/ convenience buy and it has been one of my best. So was my 1377 by the way... ; )
They are worth every penny in my opinion, but in the future I will be ordering them for $7.99 as they can be found online.
So, to officially end my problem with my supplier recrowned 2260 barrel here it is.:
The custom parts merchant emailed me and said that I could either get a $5 refund and keep the barrel, or I could send it back to him and he would recrown my barrel the normal way he does it. I sent the barrel back for $9.50 and he shipped it back to me in a week. This was super fast considering I waited 7 weeks to get the barrel initially. I was impressed there! Second, the new crown is gorgeous! It is a rounded type crown and it is polished!!!! GREAT JOB!!! did the Q tip test, and perfect! I decided to prep the breech the same as I did my stock 1377 barrel. I used wet/ dry 220, 330, and 400 grit sandpaper and polished the throat, transfer port and 1/2" lead in of the rifling. This eliminated all chance of burrs shaving pellets and I hoped it would minimize the choke at the breech end. Pushed a crosman pointed through the barrel and the choked breech still existed. I worried about this for a few days and contemplated having a gunsmith choke my barrel end, scrapping the barrel and investing in a LW blank, or Smooth Twist blank and then couldn't justify it. lol I shot groups of crosman destroyer, HPs, and pointed, but flyers were still everywhere! Sucked.... Until today! RWS super domes are cutting the same hole at 10 yrds! AWESOME!!! I now have a perfect squirrel gun! I have it sighted .25" high about to have a nice flat trajectory out to 35yds.
My rifle is finally complete and I can stop tweaking it!!!!! Now Maintenance is the only issue. Here are some pics !
very nice!
glad to here it worked out
the bad part is having to use pellets that cost more than rimfire .22lr ammo
like you said order online and the price drops but how much is the cost of shipping are you still getting a deal ???
Nice looking shooter Hoss. Is that a TKO on it?
glad you got it sorted superdomes are a good pellet, in .22 i either use superdomes or crosman ultra mags depending on the rifle some like one but not the other and vice versus
in the uk the superdomes are alot cheaper than the crosman and seem to have a better quality control as i don't find damaged skirts like i do with the crosmans
ped
The thing with cutting and re-crowning a barrel is really not just about making the crown which is relatively easy to do , but mostly cutting the barrel perfectly vertical . That is the key to a good crown. The gunsmith will use a lathe to make the cut perfectly straight .
1377x, I plan on buying from amazon using free prime shipping on my order of $25 for pellets. should be much cheaper.
Tater, that is a 6.5 carbon wrap TKO. It is super quiet with the 23.5 barrel.
ped, Crosmans are horrible... QC is not there. Non of my guns shoot them well enough for me to like them.
josey88, you're right, I think the merchant used one on mine as it is flat and shiny as it should be.
This set up is what I have been trying to achieve since 2007 when I first bought my 1377c.
This is what I have done since 2007:
$ 49 Bought Crosman 1377
$ 1.25 poly-tubed transfer port,
$ 34 installed Crosman steel breech
$ 0 lightened the valve spring, polished the sear,
$ 0 lightened the trigger to 8oz using bic pen spring, Mcdonald's straw, and one .177 Crosman destroyer pellet,
$ 2 polished the lead in with wet/ dry sand paper,
$ 8 added two more set screws to the breech ( 3 total on top) set screws and drill and tap set,
$ 39 Mellon recrowned 23.5" 2260 barrel
$ 0 free floated the Mellon 23.5" 2260 barrel (cut 1377 barrel band into a plug),
$ 30 Mellon flat topped piston and valve,
$ 0 Mellon angled the valve port,
$ 18 installed a Mellon flow thru bolt,
$ 0 modified the breech screw ( flat head),
$ 0 installed a pipe clamp to the breech,
$ 30 installed a Winchester 4x32AO scope,
$ 44 installed a 6.5 TKO break,
$ 30 installed a Crosman 1399 stock,
$ 0 put a set screw on the bottom of the 1399 stock to eliminate wobble,
$ 0 taped a chairgun 1-50yd ballistics table on the inside bottom of the stock,
$ 5 installed sticky felt tabs on the tube and in the pump are to reduce pumping noise,
$ 8 installed mellon solid pin,
Total = $298.25
That looks awesome Hoss. :-*
We need more pics!!
Here is a video with the stock barrel and tko.
http://youtu.be/InYGfHTxa4s (http://youtu.be/InYGfHTxa4s)
Seems that dog WILL hunt after all. Happy to hear it! :-*
Nice looking shooter too. 8)
Al
UPDATE(5/23/2013:
Yesterday I was at my girlfriend's parent's house and I used her father's pipe cutter to nip off the old crown and hopefully create a choke. Thus kinda worked but only at the end and created a high spot at the end where the metal deformed from the cut. So I chucked my 22" barrel into her father's drill press turned horizontal and proceeded to re-crown the barrel. I held onto the barrel with a shop towel and used a flat file to make the face perfectly flat. I then used wet/ dry 220 grit sandpaper and 3 sanded round, flat head, machine screws to shape the crown inwards I also removed the high spot with the file and sanded it smooth with the drill press. Next, I used 320 and 400 grit paper to finish the crown up. I buffed the crown with the end of a shop towel and some WD-40 and it turned out 99.99% mirror finish. I was so happy with the results that I re-polished the lead in with the 400 grit and buffed.
I was so happy with the results that I decided to redo the crown and lead in on my Beeman 1073 RS2 sportman w/ .177 barrel installed. It turned out beautifully. The barrel is factory choked and shoots Gamo hunters very well. I have ordered RWS Superdomes for it just last night. Can't wait to see how much better it groups.
Anyways, since my now 22" 2260 barrel (originally 23.5") was smooth and shiny, I thought, well theirs one variable eliminated. But then I thought what if try to fire choke the barrel? I realize that these barrels are probably button rifled and from ME courses I know that that leaves residual stress in the steel. I figured I would heat it to near or at the upper critical transition limit for steel and then quench it to shrink the barrel. I knew this from school but I got the idea to do it to my barrel from some guy on the forums. He, however, advised another guy to air cool the barrel ( annealing) not quench the steel. I decided to quench for more choke and it worked out nice. What I did was use a blue propane torch - like that used for copper pipe brazing- to heat up the last 2 inches red hot and tappered the heat back about 4 inches. I did this to create a gradual choke. after I got the barrel heated evenly, I quenched it in a glass full of iced water. I pulled a patch through with my trusty double dental floss and .177 Hunter pellet weight and sure enough it was choked at the end. Only problem was that I used water instead of oil. I wanted to use oil but I didn't want to risk it catching on fire in the garage and/ or waste a lot of her father's oil just for a barrel. Plus motor oil has lots of additives that could have impregnated themselves in the steel and yielded a discoloration.
As it were, I recrowned and sanded the barrel to ensure perfection. Later, I shot Beeman FTS, H&N baracudas, and crosman HPs at 25yds to see if the groups were better than before. Sadly, the barrel still didn't like them. So when I got home I decided to polish the internals of the barrel a bit and clean the inside of the barrel that had been choked to see if that helped. I used Crest proHealth toothpaste mixed with 10W30 non detergent oil applied to a patch and worked it up and down the barrel. It was a very tight fitting patch as to conform to the rifling. It removed the quenching surface slag and probably smoothed some of the high spots in the rifling too. I cleaned the whole barrel with brake cleaner and scrubbed it real well with a brass brush and patched. I then ran an oil soaked patch and dry patches till squeaky clean.
After this I tested the pellets again. The groups shrank in all three types about 1/2 inch@ 10 yds! Crosman HP's were shooting 1". FTS's printed same hole with 3/4 flyers after barrel got dirty. And Baracudas were at 1.25" consistently with some making .25" groupings withing the large group. I pushed a pellet through and measured 5.52mm from the 5.53mm previously. Not great but better than no choke at all. I have yet to get to try RWS superdomes ( its favorite pellet) as I had shot them all up prior to the work. But I am sure the .25" ragged hole groups I was getting before will shrink considerably @ 10 yds. I believe this because my crown wasn't as perfect as it is now and there was only a choke at the breech and now there's one tapered to the muzzle. I am excited to get my superdomes in and test them out! I will post pictures of the groups or make a video for you all when I do. here are some pictures of the two crowns an the lead in on the Beeman and the 1322.
The previous picture was the Beeman's crown. Now the crosman 2260 barrel crown.
here are the rifles side by side. I love how light my 1322 carbine is compared to the Beeman!
Nice job ... :-*
X2 :-*