Jamison Brass Availability

[Hoof Hearted]

I have a bunch of Jamison 45-75 (no it's not for sale) and I can get you whatever specs you need. It has all been fired but the rim should average out (I can take multiple measurements).

I had serious headspace problems in my Crap 76 so I installed a set of Winchester Bob's links and set the headspace using the Jamison case to minimum. The .348 "parent" that everyone is using has a much thicker rim.

I believe we should not propogate this error (just My opinion). Have Starline get as close to possible as original. By that I mean rim thickness and diameter. I realize they won't do the tapered rim (will have to be flat). By the way that "tapered" rim cures a lot of the feeding/firing errors that I have seen in these rifles

[Hell-Er High Water]

HH,

What I am interested in is the case head diameter just above the rim or just above the extractor groove if the Jamison brass has an extractor groove.  Being I have never seen any of the Jamison brass I don't know if it has an extractor groove or not.

Thanks.

HHW

[CarverTripp]

HMMM, Seems to be alot of questions as to the proper case dimensions. Now it would be great to have the cases made to the original specs. My question, would they be correct for these replicas? Is the chamber dimensions the same for both Uberi and Chap?I wonder which die set Uberti recommends. Anyone do a cerrosafe cast of the chamber to see it's dimensions?
As I've mentioned, I had Gad make up some 45-75 from .348 Win cases and what I got doesn't look anything like these drawings. I'm not sure what I should do. Will running them through the die set give me the correct dimensions? Or load and firing them to expand them to the chamber. Help!
Carver

[Hobie]

I've got some of the GAD ammo coming to me so haven't seen that but the former owner had no problems with it. 

I would think we would want to, as early as possible in the process, standardize on the standard that works and not some hodge podge derived from from some odd-ball transcription error or somesuch.  It is my understanding that the 1918 drawing has been the standard for several in the industry. 

[Hoof Hearted]

HMMM, Seems to be alot of questions as to the proper case dimensions. Now it would be great to have the cases made to the original specs. My question, would they be correct for these replicas? Is the chamber dimensions the same for both Uberi and Chap?I wonder which die set Uberti recommends. Anyone do a cerrosafe cast of the chamber to see it's dimensions?
As I've mentioned, I had Gad make up some 45-75 from .348 Win cases and what I got doesn't look anything like these drawings. I'm not sure what I should do. Will running them through the die set give me the correct dimensions? Or load and firing them to expand them to the chamber. Help!
Carver

Carver
I know we all have investments here, and feelings! But the problems we are experiencing are due to the fact that the manufacturers are not buiding the rifle to anything that resembles specs (like saami). Asking the case manufacturers to fit these ill conceived chambers is kinda "cart before the horse"
Chamber casts will be all over the board. I bought test brass from Chapparal and the discrepancies were HUGE! Meaning the reamers were changed often and many time the barrels were reamed very deeply (tapered case = bigger base).
I'll go outside and put the mic to it right now
Back in a minute with postings.

[Hobie]

I'll do a Cerrosafe cast of my chamber as well.  I really need one just for reference anyway! 

[CarverTripp]

Great replies guys, I look forward to the dimension info! I wish I could get at my 76 and check these things out but I can't it's under the tree, in a box with a bow on it  
Carver

[Hoof Hearted]

OK

At the base (right up next to the rim) 0.5475. Seems to be very unifrom no matter how many jamison cases I check.
Rim thickness is 0.060 (varies from .058 to .062) measured with a dial caliper, but this is not the best way to measure.
OAL 1.885
Neck thickness 0.010
Neck OD 0.475

This is not scientific by any means...........

I will try to attach a scan of some chamber differnces in fired brass.

[Icebox Bob]

Perhaps this thread could be moved into the 1876 board = http://www.cascity.com/forumhall/index.php/topic,15915.0.html

Just a thought
Icebox

[Hoof Hearted]

Perhaps this thread could be moved into the 1876 board = http://www.cascity.com/forumhall/index.php/topic,15915.0.html

Just a thought
Icebox

Am I lost?
Somebody please call my daddy to pick me up

[Hobie]

Perhaps this thread could be moved into the 1876 board = http://www.cascity.com/forumhall/index.php/topic,15915.0.html

Just a thought
Icebox

That's where I found the topic... 

[CarverTripp]

I think we're here already, aren't we?

[john boy]

Gents:  Here's the case specifications that Chaparral is making their brass to ... whenever it arrives in the US


Rim Thickness - .057 to .062
Rim Diameter - .620 to .629

And here's some other rim thickness and rim diameters that are being sold in the US:

                                Rim Thickness           Rim Diameter
Jamison/TenX             0.057                      0.613
Buffalo Arms               0.057                      0.605
348 Resized                0.062                      0.602
Original 1878 WRC       0.056                      0.621

[Icebox Bob]

Am I lost?
Somebody please call my daddy to pick me up

The thread I was referring to; "Chaparral M'1876 Winchester NWMP carbine" as started by Rattlesnake Jack, shows up in "The Barracks" board and not in the "The Winchester Model 1876" board when I look at it.  Just wondering if it possible to move it over here.....

I'm here, you're here, it's there;
Icebox

[CarverTripp]

I'm for that Icebox Bob, Maybe someone can move it over.
Carver

[Grizzly Adams]

I'll ask!

[Hoof Hearted]

I'm for that Icebox Bob, Maybe someone can move it over.
Carver

Ok, now I'm confused and lost
Here's where I am:
http://www.cascity.com/forumhall/index.php?topic=17904.new;topicseen#new
Re: Jamison Brass Availability

Where are you?

[Hell-Er High Water]

I sent an eMail to Lyman today asking what they are basing their 45-75 reloading die dimensions on and explaining some of the problems that have been brought up here with the apparent lack of coordination between the rifle manufactures, case manufacturers and die manufacturers up to this point.

I hope that this isn't a duplication of info that has already been posted.

When I hear back from them I will post their answers.

HHW

[john boy]

High Water - it was us boyzs down here in south Jersey that found the wrong dimensions with the Lyman resizing dies.   We compared the proper dimensions to several original 45-75 cases.  Our 'mouthpiece'  - Swiss Oscar -  fellow SASS member, called Lyman detailing the incorrect dimensions (was sizing the shoulder incorrectly).  Lyman's reply on the phone was ... OH S***! 

The new dies will be out of production this month and hopefully available in January.  If anyone has one of the incorrect resizing die, give them a call for a replacement

And for the good of all 45-75 shooters, we also determined that the initial batch of Buffalo Arms cases were also being made incorrectly.  Again, our 'mouthpiece' talked with Skip at BA and they are now being made hydraulically correct

[Grizzly Adams]

Lyman's reply on the phone was ... OH S***! 

Gotta love it!