Barrel Breech Leade Taper Rate

[Ronno6]

What is the Barrel  taper rate for a .22 barrel?
Is there a standard taper reamer to achieve this?

[Motorhead]

What application ?
 
Break barrel / PCP / Flush seat or deep seating all have a "Best" so no generic anwser here

[Ronno6]

What application ?
 
Break barrel / PCP / Flush seat or deep seating all have a "Best" so no generic anwser here

I am looking into machining a Crosman 362 barrel to fit a Daisy 822 MSP.
Requires shortening, turning the ends to fit valve body and front sight
and machining the breech ID for loading.

[Motorhead]

Not familiar ... how does the pellet load, is there a transfer port and a probe seating pellet deeper than flush ?

[Ronno6]

Not familiar ... how does the pellet load, is there a transfer port and a probe seating pellet deeper than flush ?

The pellet loads into the breech of the valve body.
The transfer port is in the valve body, not the barrel.
The barrel buts up into the valve body maybe .060" beyond the TP
The bolt probe should about push the pellet skirt at or just past the edge of the TP....
Does this mean that the barrel does not need  any taper??
That would be great!

The 362 barrel does have a TP, hence the lead taper??
That will be removed for use in the 822........

Update:
I have half of an 22X barrel that must have come from a police auction...it was cut in 2.....
A pellet dropped into the breech end drops freely so that the end of the skirt is maybe 1/8" past flush.
The pellet drops into the loading end of the bore of the 362 barrel about the same,
but when dropped into the muzzle end, the skirt comes flush with the muzzle....

So...........back to the original question, I suppose..........

Maybe just a gentle grind with a Dremel while in the lathe??

[Motorhead]

AKA:  Throat loaded where a probe pushes pellet to the far side of transfer hole, Typically a leade or free bore is made.  This free bore is basically at the pellets head diameter or a tad larger.
When pellets head passes transfer hole it is in the rifling and as skirt passes transfer hole and seated no further it is resting on transition of free bore to rifling. 
A blended in or sight ramp of rifling is best as it presses into pellet not cutting it.

Took most of the day ... Lol, hope this helps 

[Ronno6]

Mr. Scott,
I last edited my post after your reply, which I had not seen at the time.

I think I will lightly touch the bore at the breech using a Dremel and a stone while the barrel is turning in the lathe....
The OEM barrel breach sees the pellet skirt drop in about .125" past the opening when inserted into the breach.......

OK. I think I have learned the nomenclature.
First, the pellet passes thru the freebore/throat, which is straight and un-rifled.
It eventually enters the bore. which is fully rifled.
The leade is the tapered transition between the other 2 sections........now I MIGHT not sound like a complete idiot......

I have seen the leade taper listed at 1.5deg, but not specified as per side or total......

[Psipumper]

Not familiar ... how does the pellet load, is there a transfer port and a probe seating pellet deeper than flush ?

The pellet loads into the breech of the valve body.
The transfer port is in the valve body, not the barrel.
The barrel buts up into the valve body maybe .060" beyond the TP
The bolt probe should about push the pellet skirt at or just past the edge of the TP....
Does this mean that the barrel does not need  any taper??
That would be great!

The 362 barrel does have a TP, hence the lead taper??
That will be removed for use in the 822........

Update:
I have half of an 22X barrel that must have come from a police auction...it was cut in 2.....
A pellet dropped into the breech end drops freely so that the end of the skirt is maybe 1/8" past flush.
The pellet drops into the loading end of the bore of the 362 barrel about the same,
but when dropped into the muzzle end, the skirt comes flush with the muzzle....

So...........back to the original question, I suppose..........

Maybe just a gentle grind with a Dremel while in the lathe??

If the barrel is.060 past the transfer port , it should only need to be faced off square and add the smallest of deburr and polish so not to shave the pellet.
The caliber is 5.5 mm (.216”) if one needed to drill the chamber.
I haven’t gotten technical enough on the lead angle and have just polished whatever angle is on the end of reamer or drill.

[Motorhead]

1.5* would be a per side.

Tho jus at smoothed up Non abrupt entering onto rifling is all your looking for.

[Ronno6]

I was only looking for the angle to see if there was a taper pin reamer that would do the job.
But, they are way too expensive.........
So, I am going to prescribe to the old "If it looks right, it must be right" philosophy.

Thanks. y'all !!

[eeler1]

What they all said.  Most airgun barrels are already pretty close to size.  A reamer might be overkill.  Maybe think polish rather than material removal.  Myself , I wouldn’t use a dremel or stone on the leade, at least not without some practice on a scrap piece first.  You can cut a very slight chamfer at the breech, just soften the edge as the pellet enters the barrel, get rid of any sharp edge there, then polish the chamfer.  Then you could use a rod of some kind, maybe with a bit of taper as mentioned earlier here, and wrap successively coarser to finer grit wet/dry paper.  Measure how far you want to polish, mark it somehow so you go far enough but not too far, just past the transfer port.  Chuck the barrel in your lathe and jam the rod/paper in there.  Run it forward some, then reverse, do it a few times, then move on to a finer grit.  Repeat.  Polishing will open the bore just a little, but unlikely to take too much.  Shove a pellet in there every so often.  Should go in easy but get a bit tighter as it seats in place.

If you are drilling a new port into the barrel, sometimes you get burrs from the drilling, a different problem. But polishing the leade is pretty straightforward if you have a lathe.

[Ronno6]

For the Daisy 822 application, the TP is in the valve body in the throat...........not in the barrel .

The donor 362 barrel has a TP, but it will be removed when the barrel is shortened to the needed length.

[Struckat]

What is a good way to make a nice transition?
All my Crosman barrels tend to maul the pellets at the leade.

[JPSAXNC]

The leade shouldn't be loose, you don't want the pellet tipping as it's going in. Where the leade meets the rifling you want just a slight( a few thousands ) tapper or rounding on the edge of the rifling, no burrs.

[nervoustrigger]

What is a good way to make a nice transition?

Either with a rubberized abrasive bit (Cratex or equivalent), or wet sanding using a dowel, or a combination of the two.  It’s one of the topics described in the barrel troubleshooting guide linked in my signature.  I’ll keep an eye on this thread if you have questions.

[Rick67]

What is a good way to make a nice transition?

Either with a rubberized abrasive bit (Cratex or equivalent), or wet sanding using a dowel, or a combination of the two.  It’s one of the topics described in the barrel troubleshooting guide linked in my signature.  I’ll keep an eye on this thread if you have questions.

I use a dowel, aka a bamboo skewer 😂

Got the idea from Wyoman.

I use very fine grit sandpaper and just go slow (them AG barrels are soft), stopping where the TP hole ends, then I polish it with Autosol.

I wash the barrel afterwards with warm water and liquid detergent to rid of detritus before I lube it.

[eeler1]

For the Daisy 822 application, the TP is in the valve body in the throat...........not in the barrel .

The donor 362 barrel has a TP, but it will be removed when the barrel is shortened to the needed length.

Doh!  Guess that part didn't register with me, sorry.  But still, polish would be the way to go.  Lots of good tips here.

[Tack Driver 10]

Some Crosman info

[Struckat]

What is a good way to make a nice transition?

Either with a rubberized abrasive bit (Cratex or equivalent), or wet sanding using a dowel, or a combination of the two.  It’s one of the topics described in the barrel troubleshooting guide linked in my signature.  I’ll keep an eye on this thread if you have questions.

Thanks, I have those bits and will reread your guide. I likely was not aggressive enough.

Pretty sure I failed my first crown, but I had already replaced that barrel.

[Rick67]

Some Crosman info

Thanks, TD sir, I took a screenshot of it 👍