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View Full Version : Case Length on a .40-65 Ron Long



Dragoon 45
10-23-2012, 07:59 PM
I did the chamber casts. Reformed WW .45-70 to .40-65. Trimmed the cases to 2.135, chamber casts are showing a case length of 2.139. Deburred and chamfered the cases. Empty cases will chamber, but when I seat a bullet the cases will not chamber. Used an RCBS .410 expander die to bell the case mouth and used a Lyman taper crimp die to take the bell out of the case mouth after seating the bullet. The bullets are not showing any evidence of touching the lands.

When examining the case itself, I see a slight shiny spot about 1" forward of the rim about 1/8" wide. This leads me to believe I might have a high spot in the chamber, but the chamber castings don't show it.

I have read that Ron Long chambers have a neck on them, but can't confirm that with the chamber castings I have.

Suggestions, ideas?

Thanks in advance.

John Boy
10-23-2012, 09:33 PM
I see a slight shiny spot about 1" forward of the rim about 1/8" wide.Dragoon, the issue is ... the case taper area 1" from the rim of a 40-65 is smaller than the taper 1" from the rim on a 45-70:
* 40-65 = 0.446
* 45-70 = 0.495
Difference = 0.049"

To resolve, you have to run the reformed 45-70 cases through a 40-65 full length resizing die which will squeeze that taper area down to the 40-65 case specification. Be sure to properly case lube the reformed brass otherwise you'll have cases stuck in your FL sizing die

For case lube, I've found what works best is Bag Balm, that you can buy at a drug store, for normal lubing and making reformed cases. A light finger rub is all that is needed and you'll also not have a crease in the cases from too much lube ...
http://www.cvs.com/bizcontent/merchandising/productimages/large/9819300010.jpg

And make sure your bullets have a base diameter of 0.408. BTW ... Starline makes 40-65 brass

tacklebury
10-23-2012, 09:53 PM
I had some of this same issue making .40-60 Marlin from .45-70. I ended up buying .40-65 brass from ToTW instead and then it's headstamped correctly. ;)

http://www.trackofthewolf.com/Categories/PartDetail.aspx/1168/1/CASE-40-65-PACK-050

Dragoon 45
10-23-2012, 11:18 PM
I formed the brass using a Lyman full length resizer die in .40-65 using multiple passes and lubed it with Hornady Unique sizing wax during the reforming. Are you saying that there is a difference in the dimensions of the Ron Long .40-65 vs the standard .40-65 at roughly 1" ahead of the case rim? I have looked all over the place and can't find a chamber diagram of the Ron Long chamber. All my measurements of the chamber casting compared with the reformed brass, show the reformed brass at least .002" under the chamber casting dimensions.

Standard Starline 2.10" .40-65 brass will chamber in this rifle with the BACO 400 grn Money bullet seated .40" deep in the case with the two driving bands showing past the nose of the bullet. The same bullet seated the same depth in the longer reformed 2.135" WW cases will not chamber. That bullet is a bore rider and it is showing no evidence that it is engraving on the lands, so I don't think it is the bullet that is keeping it from chambering. The rifle is a Roller so there is not an option to use a camming tool.

I would like to use the longer reformed brass as it will give me a little more powder capacity. But so far it does not seem to be working.


Dragoon, the issue is ... the case taper area 1" from the rim of a 40-65 is smaller than the taper 1" from the rim on a 45-70:
* 40-65 = 0.446
* 45-70 = 0.495
Difference = 0.049"

To resolve, you have to run the reformed 45-70 cases through a 40-65 full length resizing die which will squeeze that taper area down to the 40-65 case specification. Be sure to properly case lube the reformed brass otherwise you'll have cases stuck in your FL sizing die

For case lube, I've found what works best is Bag Balm, that you can buy at a drug store, for normal lubing and making reformed cases. A light finger rub is all that is needed and you'll also not have a crease in the cases from too much lube ...
http://www.cvs.com/bizcontent/merchandising/productimages/large/9819300010.jpg

And make sure your bullets have a base diameter of 0.408. BTW ... Starline makes 40-65 brass

kokomokid
10-24-2012, 09:36 AM
I think original may have been .408. My imitation R Long chamber is 2.130 long and has a .500 neck that is .4305 dia. Starline brass is too short and a .410 bullet with thick brass is about .431 dia. A non tapered bullet may be seating at the end of the freebore and not show land marks. Good luck LB

drcook
10-24-2012, 02:05 PM
after you expand the case (and before you seat the bullet) will the case go into the chamber all the way ? (don't bell the mouth).

then bell the mouth and try the same and see if the case will seat

then try taking the bell out of the mouth and check again

what diameter bullet are you using ? what diameter is the case on the neck after seating the bullet -vs- the diameter of the neck on the chamber cast.

creep up on it in steps to see where the interference is

KHA
10-24-2012, 02:16 PM
A good way to find your problem is take a felt tip marker and cover the case and bullet and then chamber it. You will see where the ink is rubbed off. Those marks are where your problem is

kokomokid
10-24-2012, 03:22 PM
I did have to fl size my 45/70 brass on an arbor press to get it all the way into the die and tap it back out with a long 1/4 bolt. First time size only. Use plenty lube. LB

montana_charlie
10-24-2012, 04:12 PM
Empty cases will chamber, but when I seat a bullet the cases will not chamber.
After all the talk about taper differences and shiny spots, I have to ask if the above statement is still true.

Most of he Google results I get include references to "Ron Long (408)". Could it be that your chamber is too tight in the neck area to take a .410" dimension ... or has the reformed brass become too thick in the neck wall?

In case it helps, there is a depiction of a Ron Long chamber in this thread ... http://castboolits.gunloads.com/showthread.php?p=1443623

CM

drcook
10-24-2012, 09:20 PM
CM et al

the reason that the 3 of you stated after my is exactly why I suggested to work it out in stages and see where the change occurred.

and why I asked


what diameter bullet are you using ? what diameter is the case on the neck after seating the bullet -vs- the diameter of the neck on the chamber cast.

Just like using 45-120 Norma brass cut back to 45-110 length in my Shiloh, it will chamber just fine until I seat a bullet and then it is too thick in the neck to reliably chamber