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My first Crown

Started by bauercrew, June 02, 2011, 04:56:38 AM

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bauercrew

Well guys i cut my barrel down to 14 inches and here is what my crown turned out to be,it is more than the stock i hope i didnt ruin the barrel it actually looks better than the stock crown,i guess i will find out,it doesnt look polished but trust me it is. would apriciate any feed back on doing it better if needed. thanks






Cross Pistol Packer

Looks good,if it shoots straight its perfect.
Ray.
Crosmans, start as a hobby,then an obsession...

Nate

looks like you did great  :-*
as far as i can see there is nothing worng with it at all. did you use a lathe for that or a drill? when i did mine for my 1377 bullpup i used a lathe and it worked great

1377x

the best way to se if its a good crown is to shoot it.
let us know how it shoots :-*
closed mouths dont get fed

bauercrew

#4
Ok guys reassembled the gun measured out 23FT in base shot at the Gamo target that has the 9 spot for center, pumped 4 times shot 10 wad cutter pellets from crosman, gun was in a homemade rest (Not a very good one i might add)but ended up put 8 out of 10 in the 9 ring(center) :o so i guess the gun is doing what its supposed to do  ;D my method for crown is as follows

1.IF you know someone with a chopsaw BORROW it,hack saw and miterbox was tough for ME to get it square

2.I used this bit in drill to get the profile

3.Then i used the brass screw to polish

4.Then i used the brass screw wrapped with 1000 grit wet and sand

5.Then i used some fine grit auto compound to finnish

im sureThere are differant ways but this is how i did it and seems to have payed off and best part was it didnt take long THE hardest part for me was cutting the barrel

om6acw

the second pic is after or before crowning? did you have chance to get rid of the saw marks?
Ondrej

bauercrew

om6: both pics are after crown yes the saw marks were pretty much polished out i put some blueing stuff on tip cant even see crown now plus i putting a muzzle brake on anyway

packrat

WOW !!! could have fooled me....bottom  picture looks like BEFORE crowning...none the less...crown in top picture looks just fine to me...like has been said...what "WE" think matters not----it's how the gun shoots that matters...just from looking at pix, I'd be willing to bet your crown job will be just fine  :-* :-*...After I had done a few, it occurred to me that re-crowning a barrel is NOWHERE near the " mountain" it was thought to be...nice job !!

AA S410,FAC,.22,Carbine- 1740,10", "hot" valve-BIG FUN !-.177 TalonSS in BLUE
"HEY !! This gettin' old thing is NOT for sissies !"  -Packrat, Georgia, USA.

Requoil

I know most people don't have access to a lathe, but when it comes to crowning a barrel all the polishing in the world won't make the gun shoot accurately if the barrel is not absolutely precisely cut (faced off) at 90° to the rifled bore. Notice I say "90° to the rifled bore" and not to the barrel itself, some rifling doesn't travel along the axis of the barrel body, and sometimes when a barrel is cut down, the rifling is well off centre, especially frequent in some of the Chinese kit.
The function of the crowning procedure is remove any burrs or inaccuracies in the squareness at the barrels muzzle, this is to stop air exiting from one edge of the pellet before any other part of the pellet as it leaves the barrel proper, which would make the pellet slightly unstable in flight.

ShadowLurker

I have a 24" barrel on the way and I plan to cut and crown it too. Can you tell me what that bit is called and where you got it? Do most big box hardware stores carry it? Also, since Crosman barrels are not fluted, could I just use a pipe cutter? I know it would probably be time consuming but it seems a pipe cutter would ensure a straight cut. I have access to lathe if I try it and screw up. Plus, the barrels are cheap enough.

Yours looks great. I hope mine comes out as nice.

Requoil

#10
Quote from: ShadowLurker on June 20, 2011, 08:32:48 PM
I have a 24" barrel on the way and I plan to cut and crown it too. Can you tell me what that bit is called and where you got it? Do most big box hardware stores carry it? Also, since Crosman barrels are not fluted, could I just use a pipe cutter? I know it would probably be time consuming but it seems a pipe cutter would ensure a straight cut. I have access to lathe if I try it and screw up. Plus, the barrels are cheap enough.

Yours looks great. I hope mine comes out as nice.

When you say fluted, do you mean choked?

Crowning tools.............. http://www.google.co.uk/imgres?imgurl=http://home.comcast.net/~yzhu/accumount/class1/cutter/index_files/image004.jpg&imgrefurl=http://home.comcast.net/~yzhu/accumount/class1/cutter/index.html&usg=__3IoqnbSxm6HS150gyLM-IMCVg-8=&h=298&w=398&sz=30&hl=en&start=19&zoom=1&um=1&itbs=1&tbnid=3sDYiIxyyv9BxM:&tbnh=93&tbnw=124&prev=/search%3Fq%3Dcrowning%2Btool%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1T4GGHP_en-GBGB433GB433%26tbm%3Disch&ei=MJT_TZM9wYP7Bub6yasN

And I wouldn't use a pipe cutter if I were shortening one, do you know anyone with a lathe, its a simple job to face off a barrel square, and as I said previously, if it ain't square it won't crown correctly.

ShadowLurker

#11
I meant to say tapered, not fluted. I've hesitated to cut some of the barrels on my firearms because they're tapered and it's hard to get a straight cut. I figure Crosman barrels should be easy since they are straight all the way.

And yeah, I guess I'll just rough cut it with a saw and face it with a lathe. I need to learn to do that anyway so I can re-crown a few old firearms I have laying around. Just curious, why wouldn't you use a pipe cutter? I've had other experienced people (like my dad) tell me it's a bad idea but no one ever explained why. I guess if it worked, more people would do it. I really don't know.

EDIT: Wow! Those crowing tools are expensive! I was just looking for a cheap bit.

Requoil

Hi again, sorry I was wrong, when you said fluted I thought you meant choked, this is when the bore narrows very slightly at the muzzle end, but you mean tapered, which makes sense.

I might again be mistaken but if the pipe cutter is one that revolves around the outside of the tube while slowly cutting into the metal as pressure is applied then the exit hole will be reduced by this pressure, but I bet I'm mistaken again friend. :-[

As barrels are quite expensive in the UK, and the pound is losing value daily, anyone with a decent .25 barrel should do their best to make sure it is crowed to a reasonable standard, i always think that barrels are much easier to get hold of Stateside.

Best wishes bud.

arkmaker †

Pipe cutters are meant for thin walled material and the barrels are thick walled. They also work more by displacing material (pushing it to the side) under pressure rather than cutting. Also, the rollers would be under considerable strain and might no be able to make it through that thick of a wall without breaking (you're gonna need a lot of pressure). And lastly, it is gonna mark the outside of your barrel really bad.

A hack saw and a file if you don;t have a lathe handy, then just use a button head with superfine emory clothe and or polishing compound. Polishing is not needed except for appearance. A little goes a long way. Best thing about a crown job is that you will know right away if you did it right! Shoot it........... If not, try again.
Here is the easy way;
[youtube]https://www.youtube.com/watch?v=OorpZlG28fI#normal]Gunsmith - Crowning the muzzle of a rifle barrel[/url]
I Am A Natural Mad Air Gunner  -  Full Of Hot Air & Ready To Expel It Quickly!

114 Rifle, 2240XL Pistol, 1861 Shiloh Pistol, 357 Pistols, Titan GP Rifle, PM66 Rifle, 2400KT .177 LW Carbine, CZ T200 Rifle, Benjamin Discovery .177 Rifle, Hammerli 850 Air Magnum in .22

quickster47 †

A nicely polished barrel end is nice to see but it does not make the crown one bit better.  If your crown job is shooting as good as you indicated then you have nothing to worry about.  As you did add a little bluing and then a muzzle brake you are good to go, or shoot.  Just keep shooting it for a few days and make sure all is really okay with your crown.

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †