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nicholst55
04-15-2010, 02:08 AM
Okay, so what distinguishes a paper patch chamber from a non-paper patch chamber? I e-mailed Buffalo Arms asking for a recommendation for a bullet mold for paper patching my NEF Buffalo Classic .45-70, and they replied that my rifle doesn't have a paper patch chamber, and will doubtless always shoot grease groove boolits better.

On a related note, would it be possible to rechamber that barrel for say, 45-110, and cut a paper patch chamber?

Nobade
04-15-2010, 08:06 AM
What you're looking for is a chamber that is almost exactly the length of the case, with no throat present. This way the bullet doesn't have to upset into the void present in a normal chamber and then get squeezed back down into the bore.

Don McDowell
04-15-2010, 09:25 AM
A "paperpatch" chamber will be tighter in demensions than what we commonly have now, it will also have a more gradual transition into the rifling, something on the order of 7degrees +- as compared to the 45 degree commonly cut in modern rifles whose primary use is probably going to be grooved or jacketed bullets and smokeless powder.
However that does not mean that you can't make a modern chamber shoot paper patch. You just need to go with bore diameter or slightly smaller, with not much of the bullet seated in the case, and sometimes thicker brass at the case mouth will help.
Probably if you started with a .441 bullet patched to .448, you can tell real quick if there's any possibility of your rifle shooting patched.

montana_charlie
04-15-2010, 01:08 PM
On a related note, would it be possible to rechamber that barrel for say, 45-110, and cut a paper patch chamber?
The old rifles (as Don alluded to) had chamber dimensions which resulted in the brass case mouth being just right to accept a bore diameter bullet...after the case had been fired.
Modern chambers are about ten thousandths too big to get that result.

Recutting your chamber might barely work in obtaining those old dimensions at the mouth, but the reamer would have to be carefully designed, and the resulting chamber would almost have a bottleneck shape.

In addition, it might be real fun shooting a 45/110 in that lightweight rifle.

You might consider paper patching to groove diameter instead of modifying your chamber...

CM

powderburnerr
04-15-2010, 02:16 PM
you can also balance your powder charge, bullet alloy and powder granulation to get it to work just fine ,whatever bulet you choose.......
a standard chamber will not clean up bored out to 2 & 7/8 there will be a ring if you rechamber with a tight throat chamber of 470 .
you want the bullet to bump up when it is in the barrel if bore size ,groove or above you need a patch to make the transition to the barrel. you can also adjust brass thickness at the moouth to compensate,,,,,,,,,,,Dean

SmileMaker
04-16-2010, 03:00 PM
Chamber cast of my 45-90


http://i77.photobucket.com/albums/j45/OH_Smilemaker/Chamber%20Cast/IMG_3692.jpg


http://i77.photobucket.com/albums/j45/OH_Smilemaker/Chamber%20Cast/IMG_3706.jpg

1874Sharps
04-16-2010, 04:14 PM
Nicholst55,

I did somehting a little different to get around the chamber problem you cite in my Pedersoli 1874 Sharps (which I happen to love, as my user name implies). Instead of modifying the chamber I had a bullet mold cut with a fairly heavy taper. The mold casts a boolit of 520 grains at 0.448 inches at the base and 0.442 inches at the shoulder. When patched up the size increases to about 7 thousandths more. This allows the boolit to be seated pretty far out in the case and deep into the chamber but big enough at the base such that it stays put with a taper crimp. Mind you, this is not so much a target boolit, although it gives fine accuracy but rather was designed primarily as a hunting boolit. Maybe this route will work for you, too.

Lead pot
04-16-2010, 05:50 PM
SmileMaker.

What degree is the throat ?? and is that a throat you re cut or is it an original??
It looks close to what my .44-90 bn and .45-90 has.

http://i704.photobucket.com/albums/ww43/Kurtalt/IMG_0254.jpg
Kurt

SmileMaker
04-16-2010, 09:40 PM
Kurt you'll have to ask Dan Zimmerman at DZ arms. He cut the chamber in
my Hepburn.

Lead pot
04-16-2010, 10:50 PM
It's not important, maybe some day you could measure the length of the taper on your cast.

Kurt

nicholst55
04-18-2010, 12:00 AM
Thanks for the info, guys; this has given me a lot to think about. I don't guess this whole paper patch thing is going to be anywhere near as simple as I had hoped. I think I'm going to look into having a one-off barrel made for my rifle with a PP chamber. Who makes chamber reamers to cut PP chambers?

BPCR Bill
04-18-2010, 12:19 AM
Thanks for the info, guys; this has given me a lot to think about. I don't guess this whole paper patch thing is going to be anywhere near as simple as I had hoped. I think I'm going to look into having a one-off barrel made for my rifle with a PP chamber. Who makes chamber reamers to cut PP chambers?

Any of the custom reamer makers will discuss chamber dimensions with you. Dave Kiff and Pacific Tool and Guage(White City, Oregon) is a good start. Get a copy of Precision Shootings Reloading Guide, there is a list of vendors for just about anything you want done.

Regards,
Bill

Lead pot
04-18-2010, 09:02 AM
Both throats will work.
The only tough thing is getting a good paper and a lot of info has been posted on that subject.

Kurt

Don McDowell
04-18-2010, 09:38 AM
I don't think you need to spend the money on another barrel for your handirifle. The best thing to do is to get some bullets and get started wrapping them up and shooting, and see by trial and error what works and what doesn't.
Get a supply of bullets in .440- .446 diameter some 9# tracing paper, and start wrapping.After going thru all that and varying wad columns, lube cookies, lubed wads, seating depth etc, if you still can't make a patched load shoot as good as a grease groove, then maybe look into having some throat work done on the rifle. Don't forget fouling control comes into play along with powder selection.
But you need to remember those handirifles are decent guns value priced and will shoot fair at short to midrange, but if you want the best in the accuracy you need fixed barrels and standing breeches.

montana_charlie
04-18-2010, 01:02 PM
I don't guess this whole paper patch thing is going to be anywhere near as simple as I had hoped. I think I'm going to look into having a one-off barrel made for my rifle with a PP chamber.
It's true that there are chambers specificly intended for paper patching. It's also true that there are a lot of shooters using modern SAAMI chambers with paper patched bullets.

The object in any form of shooting is to get a symetrical, undamaged bullet out of the muzzle; spinning fast enough to be stable; and moving at a reasonable velocity.

In paper patching, getting the undamaged bullet is the part where a paper patch chamber may make the difference. It also depends on some other factors.

Here are two PP bullets fired from the same SAMMI chamber. One is 'damaged', the other is not. The trick is in learning how to get the result on the right all of the time.

http://castboolits.gunloads.com/picture.php?albumid=88&pictureid=1700

A paper patch chamber will not auto-magically guarantee good results.
You still have to figure out how to do things right.

CM

1874Sharps
04-18-2010, 05:21 PM
It is very true that generally much powder and lead must be sacrificed at the target range altar to the accuracy gods before success. But is that not part of the fun?!!! Wahoo, I think it is!

nicholst55
04-19-2010, 06:28 AM
More to think about... I've decided against another barrel for the Handi for a couple of reasons - one, like Don said, you are somewhat limited by the platform; two, I don't want to end up with a $1,000+ Handi Rifle! I'm sure a custom barrel (and reamer) would wind up being well north of $500 by the time I was finished.

I believe I'll shoot what I've got until I find myself being limited by the rifle, and then decide just what I want to do. A Shiloh Sharps would sure be nice, but it isn't in the cards at this time.

Actually, it's realistically going to be two more years before I can devote any effort to this project - that's when I'm scheduled to leave Korea. Maybe I'll save up my nickels and dimes and I'll be able to afford a Shiloh Sharps by that time. [smilie=1:

Thanks for your input, fellas!

Don McDowell
04-19-2010, 10:10 AM
Ya know if it's going to be two years before you get back from this tour... You may want to call the good folks at Shiloh and start the process, and by the time you get back your rifle will be ready.
Or start stuffing your pennies away and when you get back pickup an off the rack rifle, or one of C Sharps already mades.

nicholst55
04-19-2010, 06:15 PM
Ya know if it's going to be two years before you get back from this tour... You may want to call the good folks at Shiloh and start the process, and by the time you get back your rifle will be ready.
Or start stuffing your pennies away and when you get back pickup an off the rack rifle, or one of C Sharps already mades.

Good advice. My understanding is that the C. Sharps rifles have a 'modern' style chamber - is that correct?

Don McDowell
04-19-2010, 06:50 PM
I guess we'ld need a definition of "modern" chamber, but yes they do , as does Shiloh unless you provide or specify a specific chamber reamer style to be used.
Either brand of rifle will shoot paper patch just fine, you just need to find the best combination, much like your BC most likely will with enough experimentation.
I may be mistaken, but I believe Kenny W's and Rick Mulherns shilohs all have standard chambers, and they shoot paper patch and greasegroove bullets with equal efficiency.

Lead pot
04-21-2010, 12:55 AM
There is nothing more fun than shooting a black powder rifle with a long tapered throat with out using a blow tube or wiping stick by just open the breach extracting the case drop in a new round close the breach and shoot again and again busting rocks or bowling pins[smilie=w:
With the tapered chamber you can do this using a GG or patched bullet at groove diameter or under and get very good results.
I have a old Pedersoli Quigley rifle I re cut the throat and I have a great time using the barrel sights and doing just this out to 800 yards.


Kurt

montana_charlie
04-21-2010, 01:31 PM
I have a old Pedersoli Quigley rifle I re cut the throat and I have a great time using the barrel sights and doing just this out to 800 yards.
Exactly how much of the throat did you modify?
Is it still capable of it's original accuracy level...when you aren't just having fun?
CM

Lead pot
04-21-2010, 01:34 PM
It was a .45-70 to start and I put my 5 degree throating reamer in and turned it out to a .45/2.4

montana_charlie
04-21-2010, 05:11 PM
Will that reamer work on a chamber you don't want to deepen...just trim down the 'step'?
Or to put that another way, do you have a drawing of that reamer?
CM

Lead pot
04-21-2010, 05:42 PM
Yes it will do this But you should have the reamer made to the specs of the chamber and bore of your rifle.
I made a chamber cast and sent it with my numbers I wanted.
I had the reamer made for the Shiloh and had two different pilots made up for the pedersoli.
The Pedersoli chamber is a little larger than the Shiloh but it worked out good as is. I cant see the original ring that came out when I deepened the chamber from 2.1 to 2.4.

Kurt

montana_charlie
04-21-2010, 07:09 PM
The Pedersoli chamber is a little larger than the Shiloh but it worked out good as is.
I don't know how to interpret what you mean by 'is a little larger'.
Was the chamber larger before you started cutting...or did it end up being larger?

And the term 'larger', itself...is that 'deeper', or bigger in diameter, or something else?

I have another question (or two), but I'll keep this simple...
CM

Lead pot
04-21-2010, 07:37 PM
CM

the chamber cast of the Shiloh measured .4807 at the case mouth the free bore diameter was .4583 at the start of the lead.
The pedersoli had a case mouth diameter of .4832 and the free bore diameter was .4612

montana_charlie
04-21-2010, 08:34 PM
Ah! That tells me a lot, actually.
And...you say a single reamer worked for both chambers by using the correct pilot for the Pedersoli bore.

My next question...
Being that it is made for deepening a chamber, that reamer had to cut a brand new leade into the rifling. (I'm not talking about the 5 degree 'chamber transition step' here...I mean the tapered ends of the lands which shoehorn the bullet into the rifled bore.)

What is the angle of that new leade...or does the 5 degree zone which eliminates the 'step' just cut straight into the lands?

CM

Lead pot
04-21-2010, 10:21 PM
5° to a 2°-30'

Kurt

montana_charlie
04-21-2010, 10:44 PM
So, a 2.5 degree leade. I think that angle and a .05" freebore comprises the standard Shiloh throat.

Last question...
What is the length of the 5 degree taper, and can you confirm it's diameter goes from ~.480" to ~.458"?

CM

Lead pot
04-22-2010, 12:09 AM
Shiloh has no free bore just the compound lead of 45 degrees into the 2-1/2 degree lead.

The 5° is .128"

"and can you confirm it's diameter goes from ~.480" to ~.458"?"

I could, but I haven't made a chamber cast after I cut it to measure it, and I did not check out the reamer because it has a odd number of flutes.

Kurt

Lead pot
04-22-2010, 07:19 AM
Cm.

A word of caution.

From your questions it makes me think that you are thinking about changing the throat in your rifle.

You can screw up a chamber running a throating reamer in the existing chamber by having the throater misaligned if you dont use the proper precautions when you use this reamer with a T handle. You want to remember that the case has a taper and the chamber side walls will not support the reamer shank till the cut is complete. Just the pilot is not enough to keep the reamer centered, you also need a bushing on the stem of the reamer with a proper fit in the rim recess to keep it aligned or you might cut an off center throat and that will throw a monkey wrench in the works and you will be looking for a new barrel.
It is best to use a lathe and indicate the setup to do it right.

Kurt

montana_charlie
04-22-2010, 01:25 PM
Thanks for the answers, Kurt.
I am aware of the need to ensure concentricity. My current concern is how to gage, and limit, depth of cut to .09 in.
That would shave away the 'step' without touching any other steel within my particular throat.

CM