GTA
Airguns by Make and Model => Artemis/SPA Airguns => Topic started by: elmury on October 10, 2021, 12:15:03 PM
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Hi all,
I wish to shorten the length of my Artemis CR600W .177 CO2 air rifle barrel.
After pushing pellets manually through the bore I notice;
- a narrow part in the beginning
- a wider part in the middle
- and a narrow part at the end of the bore.
So, in contradiction to many other CR600W owners/reports here on GTA, it seems my barrel is choked.
(perhaps European models come with choked barrels?)
Anyway, as I have understood, manufacturers choke their barrels to make them less pellet fuzzy.
Does all this mean that I can go on and cut my barrel, loosing the choke, re-crown it and end up having a nicely shooting un-choked barrel?
Lex.
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Throw the dice….see if it comes up odd or even? No one can tell if it will shoot as good, worse, or better (just that its most likely to shoot slower).
With a tight spot at the breech and a tight spot at the muzzle...the muzzle end could be intentional or by accident. Pretty sure the breech end tight spot is by accident.
Couple of questions:
Sure it’s a tight spot at the breech..not the o-ring in the barrel, the start of rifling engraving the pellet, or a burr?
SUSPECT that the Gen 2 barrels (Storm-rider barrels are the same as the 600W barrels) might show a slight muzzle choke, likely due to the way they are threaded for the new style LDC.
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Usually think about “worst case” ( in case the dice toss came up “craps”) and look on-line before I reach for the hack saw. Really hesitate to cut a good shooting $200 barrel in the hopes of turning it into a great shooting barrel.
Thinking the replacement barrel cost for that rifle would be more like $35.
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@Ribbonstone
I think you are correct. I have the Gen 2 barrels on my CR600W and CP2 pistol/rifle.
The ones with the screw on LDCs.
About the narrow spot at the breech side;
Could it be that it only feels tight and narrow but actually is the rifling that is being cut into the pellet?
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'Likely' is my best answer...there is a larger/non rifled short smooth bore section (if it were a firearm, would call it the "chamber") leading up to the rifling, so it always feels like a restriction when the rifling starts to engrave the pellet.
Took me like 5 weeks of thinking about it to get me to cut off a .177 QB79 barrel to carbine....just to match a previously done .22 QB 79 carbine. Shot so good uncut, was really hesitant to cut it just to make a set of "twins".
Same kind of care getting a good crown as any other barrel.
Grouped just as well as before....just shot a different pellet best and was a bit slower.
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'Likely' is my best answer...there is a larger/non rifled short smooth bore section (if it were a firearm, would call it the "chamber") leading up to the rifling,
I think that section is called "leade" with airguns?
so it always feels like a restriction when the rifling starts to engrave the pellet.
Ok. Must be it then. So no tight area at the breech side. Just at the muzzle. Makes sense.
Took me like 5 weeks of thinking about it to get me to cut off a .177 QB79 barrel to carbine....just to match a previously done .22 QB 79 carbine. Shot so good uncut, was really hesitant to cut it just to make a set of "twins".
I can imagine that took some real hard thinking!
But the QB79 barrel just looks so awfully long. Especially with a LDC attached.
Grouped just as well as before....just shot a different pellet best and was a bit slower.
Good to hear that It all worked out fine.
I'm getting all confident now:)
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@Ribbonstone
Btw, did you re-crown those QB79 barrels yourself?
If so, how did you do it?
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Make a square cut, then use a brass screw with an abrasive compound to establish a burr-free bevel.
My CR600W had rifling damage at the muzzle so I chopped and recrowned it with this method. The result:
(https://i.imgur.com/vyfevrC.jpg)
A more detailed writeup on the CR600W:
https://www.gatewaytoairguns.org/GTA/index.php?topic=143793 (https://www.gatewaytoairguns.org/GTA/index.php?topic=143793)
And a barrel troubleshooting and accurizing how-to:
https://www.gatewaytoairguns.org/GTA/index.php?topic=130555 (https://www.gatewaytoairguns.org/GTA/index.php?topic=130555)
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@nervoustrigger
Yes, I had read your posts about the CR600W.
Very nice result. Also nice grouping at 25/43 yards!
However, I didn't quite get the squaring up part using the drill press + emery wheel?
So the barrel spins in the drill press and the emery wheel spins as well in a dremel??
Anyway, I'm thinking of using a sander to square up the muzzle face.
(see attachment)
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Same basic plan...although as the crown was always going to be covered by an LDC, didn't bother to mirror polish it or bee as deeply recessed.
Just eyeball work to get it to flat....machinist square, files, time...once it is really squared, then the brass lap and polishing.
Good luck with the cut-job. it's a bit of a random thing, the spot you pick for the cut can be less nice than the parts you cut off.
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I didn't quite get the squaring up part using the drill press + emery wheel?
So the barrel spins in the drill press and the emery wheel spins as well in a dremel??
Right, you got it. Barrel spinning in the drill press, emery wheel spinning in the Dremel. Slowly bring in the edge of the emery wheel until it just kisses the muzzle. Don't push the wheel into the muzzle, do your best to hold it so the abrasive only wears down the high spots as the barrel goes round and round. Eventually the skipping you feel and hear will become continuous and you'll know the end is square.
Your sander idea can work well also. I would advise rotating the barrel on a near continuous basis as it approaches being finished, that way any potential lack of squareness will simply become a slightly convex face concentric to the OD, provided the bore isn't badly out of center. If it looks centered, you should be well poised to achieve a better result than the factory.
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@nervoustrigger and @Ribbonstone:
Thanks guys for all the tips.
So both you guys own the CR600W (= mrodair SPA plinkster) as well.
I have seen both your target scores at https://www.gatewaytoairguns.org/GTA/index.php?topic=143793.20 (https://www.gatewaytoairguns.org/GTA/index.php?topic=143793.20)
at 25+ yards. Very nice!
I am shooting at 12 meters (~40 feet on my AO scope) indoor bench rested and have a really hard time getting it to group well.
At that distance and conditions it should be literally hole in hole.
Instead the groups are 12 to 15 mm center to center at best!
Been through the usual;
- barrel cleaning
- pellet choice
- manual single shot loading
- LDC on/off, clipping check
- chrony testing (no weird fps changes detected)
- scope swap
- leade and TP hole burr smoothing
- barrel band tight/loose, on/off, change position
So 2 suspects remain:
- bad crowning
- barrel harmonics (very thin long barrel)
(sorry for the metrics)
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It’s an old one (Gen I) as sold by MrodAir as the “Plinkster”. Tried it with two bands (one borrowed from the PCP version), one band, loose band, and no band.
Two bands didn’t make any difference, one tight band worked just as well, loose band or no band shot worse. Did exchange the horrible Gen I LDC for a better LDC, adjusted the trigger, got the safety working with the adjusted trigger, but still running the factory crown.
Might be realistic expectations. Would NOT be happy with the 25 yard groups with a rifle I had hopes for being a 1” at 100 yard rifle. Am pleased with it as a co2 rifle that won’t get used past 30-35 yards.
Bought it about 2016...so 5 years of being used. Changed the o-rings, changed the 12gr. seal, and broke the bolt handle (which seems to happen to both the PCP and Co2 versions on occasion).
Look at it this way. IF you cut the barrel, you’re going to have to recrown. If you recrown it full length, you may now want to cut it. Worst case, you get practice at re crowning.
As a practical matter, if you've not recrowned barrels before, once you cut off the barrel...use the cut off length as practice.
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Might be realistic expectations. Would NOT be happy with the 25 yard groups with a rifle I had hopes for being a 1” at 100 yard rifle. Am pleased with it as a co2 rifle that won’t get used past 30-35 yards.
Of course, I too would be happy with your results at 25 yards, but I am talking/shooting 13 yards (12 meters)!
At such short distance, indoor, bench rested, with scope, .177 at ~590fps it should be literally hole in hole or at least under 10mm (~0.4") groupings.
Am I not Right?
My Artemis CP2 (which is practically the same gun as the CR600W) in pistol mode does exactly that; hole in hole.
As does my unregulated BSA Buccaneer .22 PCP (ok maybe different league gun).
So there's something really funky going on with my CR600W rifle/barrel.
I'll try to post a picture of the muzzle crown.
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Both of my SPA-made long guns had damaged rifling at the muzzle. They were purchased 2 years apart from different vendors so it seems to be a systemic quality problem rather than an isolated issue.
Meanwhile, none of the 3 pistol-length barrels had the problem.
https://www.gatewaytoairguns.org/GTA/index.php?topic=166821 (https://www.gatewaytoairguns.org/GTA/index.php?topic=166821)
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1. Could be worrying about the wrong end.
The barrel is held to the action by little set screws. On my old one, both the set screws were kind of rounded looking and stripped.
Didn’t shoot well because the breech end of the barrel wasn’t tight. Wouldn’t tighten because the screws were stripped (or just made crappy).
Actually think the screws were bad rather than the threaded holes...swapped screws with the ones on the old LDC, which seemed to cure it..started shooting well because the butt-end wasn’t “wiggling”.
The PCP version was ordered at the same time...didn’t have that problem...so it’s not a universal problem
2. Go ahead and play with the barrel band. If tight band vs. loose band shows a BIG difference in point of impact, pretty good indication that the band is stressing the barrel in some way.
3. Every barrel maker screws-ups now and again….generally, the expensive barrels are QC better and the turds are likely to get rejected. it’s much more common with “cheap” barrels.
Does seem that for about $35 you could replace it (I’d go with a GEN 2 barrel...which would fit, and give you a threaded end to attach a different LDC.
Same inexpensive replacement cost would make experimenting with crowns/lengths much more attractive...worse case, are out $35 to start over and you’ll learn a whole lot along the way.
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Both of my SPA-made long guns had damaged rifling at the muzzle. They were purchased 2 years apart from different vendors so it seems to be a systemic quality problem rather than an isolated issue.
Meanwhile, none of the 3 pistol-length barrels had the problem.
https://www.gatewaytoairguns.org/GTA/index.php?topic=166821 (https://www.gatewaytoairguns.org/GTA/index.php?topic=166821)
Aha, now we're getting somewhere.
Same here; the CP2 pistol barrel shoots great, the longer rifle barrels not!
Have tried them both. Same inconsistent groupings.
Note that these are all GEN 2 barrels. The ones with the threaded muzzles.
After visual inspection it seems the pistol crown looks smoother then the rifle crowns.
I did not see any rifling damage like in your photos.
I think I'll try a re-crown first whilst keeping the threaded muzzle section.
Don't know if enough thread length remains since the sunken crown part is quite deep:)
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1. Could be worrying about the wrong end.
The barrel is held to the action by little set screws. On my old one, both the set screws were kind of rounded looking and stripped.
Didn’t shoot well because the breech end of the barrel wasn’t tight. Wouldn’t tighten because the screws were stripped (or just made crappy).
Actually think the screws were bad rather than the threaded holes...swapped screws with the ones on the old LDC, which seemed to cure it..started shooting well because the butt-end wasn’t “wiggling”.
The PCP version was ordered at the same time...didn’t have that problem...so it’s not a universal problem
2. Go ahead and play with the barrel band. If tight band vs. loose band shows a BIG difference in point of impact, pretty good indication that the band is stressing the barrel in some way.
3. Every barrel maker screws-ups now and again….generally, the expensive barrels are QC better and the turds are likely to get rejected. it’s much more common with “cheap” barrels.
Does seem that for about $35 you could replace it (I’d go with a GEN 2 barrel...which would fit, and give you a threaded end to attach a different LDC.
Same inexpensive replacement cost would make experimenting with crowns/lengths much more attractive...worse case, are out $35 to start over and you’ll learn a whole lot along the way.
1. I wish that was the problem. Alas, the 3 barrel screws are ok on the gun.
2. I played with the barrel band a lot and it's impact on POI is huge.
As with most of these cheap "receiver/barrel over tube" constructions the barrel points a bit upward and is bend down by the band towards the tube.
3. I don't think these barrels are sold separately (as a replacement part) here in Europe.
That's why I'm a bit reluctant to mess it up.
btw, these are gen 2 barrels that I have.
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Hi all,
I wish to shorten the length of my Artemis CR600W .177 CO2 air rifle barrel.
After pushing pellets manually through the bore I notice;
- a narrow part in the beginning
- a wider part in the middle
- and a narrow part at the end of the bore.
So, in contradiction to many other CR600W owners/reports here on GTA, it seems my barrel is choked.
(perhaps European models come with choked barrels?)
Anyway, as I have understood, manufacturers choke their barrels to make them less pellet fuzzy.
Does all this mean that I can go on and cut my barrel, loosing the choke, re-crown it and end up having a nicely shooting un-choked barrel?
Lex.
Not PCP related but that is what I did when I bought a .177 R1 barrel, then did a home "chop and choke" and the results were good.
The first choke job was using a large pipe cutter where I turned rollers 01 tool steel rollers to replace the existing "cutting rollers". This worked, however it also damaged the muzzle finish..........
(https://i.imgur.com/0fzwQhg.jpg?1) (https://i.imgur.com/plO7MWF.jpg)
My next scheme was to make a "choke clamp" from the head of a 1" grade 8 hex head bolt. The head of the bolt was bored with a hole .005 larger than the muzzle OD, then hack sawed across the "corners" so the kerf of the hack saw blade would form the relief for compressing the muzzle using a heavy 5" bench vise............
(https://i.imgur.com/pyLIXaE.jpg) (https://i.imgur.com/UlVj0qA.jpg) (https://i.imgur.com/E5xGWWO.jpg)
The choking was done by pushing a new pellet through the bore after the "swage" and gaging the amount of choke "by feel". This needed to be done several times pushing a new pellet through the bore till the greatest restriction during the trip through the bore was at the choke. This took a lot of "vise pressure" requiring a long "cheater bar" on the vise handle. When the choke was finished the tightness was only about 3/4 that of a HW factory choke but the resulting accuracy was excellent. After shooting the first group at 50 yards (sitting on a bucket resting the gun on cross sticks "hunter class field target style") I was impressed so I took a few more shots to zero the poi on the 50 yard bull and shot the second 5 shot group instead of using holdover. Funny thing is that the chopped R1 barrel on my R9 was the only barrel I've had that shot Beeman FTS pellets well.........
(https://i.imgur.com/daG1cT8.jpg)
Anywhoo, I don't know how relevant but home choking can be done, however a lot of hassle.
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Yeah if the crown looks gnarly, a first attempt at dressing it sounds like a good plan. Let the abrasive do the work. Don’t apply pressure more than roughly a pound or so…meaning less than the weight of the drill itself when working with the muzzle pointed up. And keep the drill moving in a random orbit to avoid developing a lopsided bevel.
However I’m a little alarmed by your comment about the thread length and depth of the crown. Sounds pretty sketchy if it’s so deep that removing it would remove nearly all the threads. For example when I had to shorten mine to get rid of the damaged rifling, there was still adequate threading remaining. The OEM crown should be nowhere near that deep.
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Just going to mention something about depth of the crown recess.
Have a couple of very good shooting BSA .177 springers.
The muzzle looks like an 8mm air gun.
They didn’t do it by hand...they backed bored the rifle from the muzzle for about 1.2”….and formed the .177 crown way down in the back-bored hole.
Taking a look with a light.,..down in that 1.2” recess is a nice even flat crown with a good smooth radius at the rifling.
The other extreme is the dead flat crown put on Colt cap-n-ball barrels (and good reproductions). Nice even smooth tiny radius for the rifling…..but they “ding” easy (almost defy you to find an original that’s not AFU).
The dept of radius is for ding-protection...smooth and even is for accuracy. If it’s hidden under an LDC or inside a shroud, ding protection is already a given.
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Right, nothing inherently wrong with the crown being recessed. But it is suspicious to see it on a barrel that historically never has been.
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Just a bit of minor “stuff”. Deep recessed crown has save the look of several center-fire military rifles that I didn’t want to cut short.
Thinking the 2nd and 3rd line troops, when the officer saw them just goofing around, got them to polish and clean for inspection a whole lot. WORSE with muzzle loaders. Muzzles looked like blunderbusses.
Back boring for 1” and re crowning in that recess preserved the (critical) visual for movie prop/ historic re-enactors that wanted them to look “right” but still shoot well when not play-acting.(in Hollywood, many of them are back bored/tapped, blank firing restriction added down in the bore where you can't see it).
So far, airguns haven’t had that issue of visual authenticity Cut it slightly longer than desired and crown it, Work in “stages” if need be. If the first crown doesn’t look right...cut it ¼” and try again. Takes me about 3 trys before I give up and buy a new barrel.
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Ok, it looks deeper then it actually is but I'll loose at least ~3 mm to cut it straight.
Hmmm, I took a picture but the forum won't let me upload it as an attachment (to big??) and I'm not allowed to put a external link??
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Ok, I ordered the aforementioned sander.
I have 2 remaining questions.
1. what diameter should the head of the famous slotted brass screw be for a .177 crown?
2. how to safely remove the plastic front sight on the GEN 2 barrels?
The 12mm hole in piece of wood trick?
Anybody knows if it's glued on or pressed on?
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If the first crown doesn’t look right...cut it ¼” and try again. Takes me about 3 trys before I give up and buy a new barrel.
I don't like that last sentence ;)
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A #6 round head screw is my preference for .177.
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A #6 round head screw is my preference for .177.
Thanks. Pardon my ignorance but what does #6 mean in metrics?
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An example:
https://www.mcmaster.com/92453A151/ (https://www.mcmaster.com/92453A151/)
I don’t know of a metric equivalent but if you are shopping around, look for a true round head, not a pan head or truss head or some other semi-round head. Here in the US they are almost always found with a slotted drive, sold in small quantities as a decorative screw for an antique sort of appearance when mounting brass hinges and such on vintage woodworking.
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I don’t know of a metric equivalent but if you are shopping around, look for a true round head, not a pan head or truss head or some other semi-round head. Here in the US they are almost always found with a slotted drive, sold in small quantities as a decorative screw for an antique sort of appearance when mounting brass hinges and such on vintage woodworking.
Thanks a lot. Now I know what to look for.
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Hi all,
I wish to shorten the length of my Artemis CR600W .177 CO2 air rifle barrel.
After pushing pellets manually through the bore I notice;
- a narrow part in the beginning
- a wider part in the middle
- and a narrow part at the end of the bore.
So, in contradiction to many other CR600W owners/reports here on GTA, it seems my barrel is choked.
(perhaps European models come with choked barrels?)
Anyway, as I have understood, manufacturers choke their barrels to make them less pellet fuzzy.
Does all this mean that I can go on and cut my barrel, loosing the choke, re-crown it and end up having a nicely shooting un-choked barrel?
Lex.
Sorry about being late to this game. Here's my experience with a barrel just like yours.
If it's tight some of the way down and then gets loose then hits the choke, if you remove that choke then you may as well junk the barrel. That choke is the only thing giving that barrel it's accuracy.
I have (had) a hatsan barrel like that and I wanted to remove the choke to shoot slugs. At first I bored out the end, like an old BSA springer, with no luck. I though it was because I hadn't crowned it correctly. So I hacked off the end and turned an 11° target crown and polished it all up and it was still &^^&.
The pellet would lighty rattle in the last 1/3 of the barrel length when you pushed one down the bore to the loose area and shook it.
If you slug the barrel and it feels the same all the way down or has some little tight spots but could be polished up to feel smooth THEN gets tight at the choke, then you have a good chance of shortening it without any problems.
My now scrap barrel ended up becoming a breach donor to a slug liner conversion.
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Sorry about being late to this game. Here's my experience with a barrel just like yours.
If it's tight some of the way down and then gets loose then hits the choke, if you remove that choke then you may as well junk the barrel. That choke is the only thing giving that barrel it's accuracy.
I have (had) a hatsan barrel like that and I wanted to remove the choke to shoot slugs. At first I bored out the end, like an old BSA springer, with no luck. I though it was because I hadn't crowned it correctly. So I hacked off the end and turned an 11° target crown and polished it all up and it was still &^^&.
The pellet would lighty rattle in the last 1/3 of the barrel length when you pushed one down the bore to the loose area and shook it.
If you slug the barrel and it feels the same all the way down or has some little tight spots but could be polished up to feel smooth THEN gets tight at the choke, then you have a good chance of shortening it without any problems.
My now scrap barrel ended up becoming a breach donor to a slug liner conversion.
Hi, thanks for your reaction.
Yes, that's exactly the horror scenario I was/am afraid of.
So I decided to try a re-crown first.
On the other hand, sometimes I think my barrel isn't intentionally choked at all but got "choked" by pressing on the front sight in the factory.
These are very soft and thin barrels.
Also, with these very cheap airguns, why go to the extra costs of adding a choke?
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[/quote]Hi, thanks for your reaction.
Yes, that's exactly the horror scenario I was/am afraid of.
So I decided to try a re-crown first.
On the other hand, sometimes I think my barrel isn't intentionally choked at all but got "choked" by pressing on the front sight in the factory.
These are very soft and thin barrels.
Also, with these very cheap airguns, why go to the extra costs of adding a choke?
[/quote]
I think sometimes they put the choke on to make up for a poorly made barrel. It brings the pellets back into good contact with the rifling for the last inch or so to get it true again. It saves having to make a perfect barrel. But there's also some great barrels out there with chokes on them too so 🤷♂️
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Hi, thanks for your reaction.
Yes, that's exactly the horror scenario I was/am afraid of.
So I decided to try a re-crown first.
On the other hand, sometimes I think my barrel isn't intentionally choked at all but got "choked" by pressing on the front sight in the factory.
These are very soft and thin barrels.
Also, with these very cheap airguns, why go to the extra costs of adding a choke?
[/quote]
I think sometimes they put the choke on to make up for a poorly made barrel. It brings the pellets back into good contact with the rifling for the last inch or so to get it true again. It saves having to make a perfect barrel. But there's also some great barrels out there with chokes on them too so 🤷♂️
[/quote]
"they put the choke on to make up for a poorly made barrel"
The HW barrels are pretty good factory barrels however the "barrel assembly" does have something to do with the consistency of the bore diameter. For example, the HW95 barrels were pressed into a barrel pivot block and pinned for decades. The action of pressing the barrel into the barrel pivot block gives a tight bore at the pivot block area, then the bore opens up to the nominal dimension. It's my opinion that the choke at the muzzle is to simply guarantee that the tightest part of the bore is the last 3/4" or so at the muzzle. Just for grinns I pushed a few new CPLs through the bore of my HW break barrel and made this "map"......................
(https://i.imgur.com/zOOXjH2.jpg) (https://i.imgur.com/qYyHXeC.jpg)
I used to also think the choke was created by the pressing in of the front sight dovetails but changed my mind after buying a newer Beeman R9 years ago which came with no factory sights yet the barrel was still choked. Factory R9 barrel pivot block and muzzle break..........
(https://i.imgur.com/OhZkBfv.jpg) (https://i.imgur.com/MQZN7i5.jpg)
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I used to also think the choke was created by the pressing in of the front sight dovetails but changed my mind after buying a newer Beeman R9 years ago which came with no factory sights yet the barrel was still choked.
Yes, but that would merely indicate that in general Beeman R9 barrels are choked, with or without front sight.
It doesn't rule out unintentional choking by front sights on other brand barrels does it?
In my case with the SPA barrels, forum users here have reported unchoked barrels on them.
So I'm not convinced yet that I have a intentionally choked barrel.
(partially wishful thinking I admit)
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Comment about cutting back ¼” and trying 3 times….figure if I got 3 good crowns and the barrel still won’t shoot, something besides the crown is wrong and I need to reevaluate.
Only problem with the slug by feel type of choke checking is that you can't feel the difference between a slight choke and a rough spot.
Can see that you want to save the threaded section; limits how much you’d want to trim off. Doubt I could make a good deep recess crown without a lathe.
Just to be sure...this is a shallow recess crown (borrowed picture):
(https://live.staticflickr.com/65535/50573011043_1e02f89b59_n.jpg) (https://flic.kr/p/2k3XUfg)rs_kimber-model-8400_d (https://flic.kr/p/2k3XUfg) by Robert Dean (https://www.flickr.com/photos/144930793@N07/), on Flickr
If the recess was removed, but the flat crown protected by being inside a shroud or covered by an LDC, would still work. The recess is a “bumper guard”.
Chokes work...likely for the reasons mentioned….what you find once you remove the chocked section might work great, might be pellet picky, or might not shoot well at all.
Mostly worked on cheap barrels (Crosmans/QB’s) and saved more of them that I lost….a few ended up as tomato stakes in the garden.
Common on Crosman were chatter marks in the bore, likely from the pilot on the cutter…the lands are kind of chewed up for the last 2/3”. Hi-speed mass production probably is at fault (clamped in it’s high speed jig misaligned during it’s few seconds of cutting).
Old QB barrels seemed to have random tight and loose spots. Have to say, the newer ones don’t suffer nearly so much from that. Have saved one (that is an excellent shooter) by cutting 4 ½” off ; the tight spot became a choke.
Not dealing with heat expansion, air gun barrels can shoot great with slightly off center muzzles.
Long explanation….its how they USE to make nearly all barrels. Bore a hole in a barrel blank and pass a rifling broach/button though. May not end up with the muzzle dead center in the blank. Blank lathed on hole center so the holes come out looking even at the two ends.
In between the breech and the muzzle, that hole can wander a bit. Often find a cut off barrel with the hole off center.
(https://live.staticflickr.com/65535/51581807205_69d70271d9_t.jpg) (https://flic.kr/p/2mA7fcx)f5a62be2-7e44-48ca-a8cd-b50770dc6721 (https://flic.kr/p/2mA7fcx) by Robert Dean (https://www.flickr.com/photos/144930793@N07/), on Flickr
This cut off one is visually off center….but it shoots so well, I’m still using it years later.
A mystery solved by re crowning:
Thought it real odd how this muzzle:
(https://live.staticflickr.com/65535/51205033551_c1dedf97ce_n.jpg) (https://flic.kr/p/2m1Pbw4)Image13_zps5879b8b9 (https://flic.kr/p/2m1Pbw4) by Robert Dean (https://www.flickr.com/photos/144930793@N07/), on Flickr
Tossing out pellets shaped like this:
(https://live.staticflickr.com/65535/51205803044_d7a768464b_n.jpg) (https://flic.kr/p/2m1T8gb)Image57 (https://flic.kr/p/2m1T8gb) by Robert Dean (https://www.flickr.com/photos/144930793@N07/), on Flickr
Recrowning...and it make sense (and shot better with out the round-disguise).
(https://live.staticflickr.com/65535/51205803364_d1e1ae791a_n.jpg) (https://flic.kr/p/2m1T8mG)Image100-1_zpsa7607d53 (https://flic.kr/p/2m1T8mG) by Robert Dean (https://www.flickr.com/photos/144930793@N07/), on Flickr
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Well I'll be darn.
1. Moved the barrel band to front (again) and tightened it normally.
10 shots first left target, .....mehhhhhh
2. Clamped the barrel down with the rear sight screw. (see pic)
5 shot second left target, .... almost hole in hole!
Hand drawn target dia ~8mm (~0.3")
Distance 12 meter (13 yards)
I dare not take the next 5 shots :o
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Next 5 shots would also be hole in hole if I were a better shooter ;D
I definitely rushed myself in the excitement.
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At this point....are you going to wonder "why"...or are going to just accept "what is"?
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At this point....are you going to wonder "why"...or are going to just accept "what is"?
Intelligent question! (don't get those too often these days)
The answer is both. I'm curious by nature so I will always want to know the why of most things.
To be clear. I enjoy trying to make this gun more accurate.
To me that's a big part of the hobby.
I enjoy the learning, reading posts from experienced people, like yourself, here on these forums.
The stories, the techniques, the tinkering and the science behind it etc. etc.
So yeah, I keep on wondering, tinkering, shooting and having fun!
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That was the right answer.
You'll fit in just fine here!