40-65 Ron Long

[SharpsShooter]

Anyone have a drawing for this annoying cartridge?


SS

[Tom Myers]

Anyone have a drawing for this annoying cartridge?
SS

Yeah, I do.

I replaced the barrel on a Pedersoli I purchased about 8 years ago that had a messed up chamber with a Green Mountain 1:14 twist and chambered it with a 40-65 Ron Long Chamber Reamer that I found cheap on eBay.

The only problem that I really have with the chamber is the length.
If I would have had my wits about me when I chambered the barrel, I would have stopped short and then deepened the rim cut with the lathe bit.

The throat was supposed to have been cut with a 0.409 reamer but it was mislabeled and cut at 0.4105 so things are a bit tight in the neck area but it still works with Winchester brass or turned case necks.

I cut the throat deep so as to load the bullet out far enough to get 70 grains of powder behind it .

Anyhow, the chamber cuts at a length of 2.155 and finding or stretching brass to fill that length is a pain. Best bet is to form the brass from 45-90 cases and then trim to fit.

I'll post images of the Chamber and throat loaded with a Snover bullet

Hope this helps.

http://www.tmtpages.com/LinkSkyImages/forum_images/40-65_Ron_Long/40-65_Win_Ron~Lyman_Mold_410663-Throat.Jpg

http://www.tmtpages.com/LinkSkyImages/forum_images/40-65_Ron_Long/40-65_Win_Ron~Lyman_Mold_410663.Jpg

[SharpsShooter]

YOU DA MAN TOM! Thank you! I was hoping you would chime in on this one. This cartridge has been a pain in the rear. I had a lee 40-65 die that I had a buddy turn .300 off the bottom and then I removed the threaded portion that retains the decapping stem and faced it off...basically creating a R.L. die

New Remington 45-70 brass measuring 2.10 comes out of this die at 2.145-55. The will not chamber until I trim them back to 2.130. Then they drop in and out. Shiloh cut this chamber.


Strange cartridge case.......

SS

[kokomokid]

This one will go into my records as I have one that likes .410 bullets but has to have the necks turned as anything over .431 will not chamber. Thinking of haveing a neck reamer ran in it but it shoots pretty good as is. Likes a snover better than anything else I have tried.

[SgtDog0311]

Tom, hoping you see this - any idea what the taper angle is on the tapers body of a 40-65 case? Fiddling around with lapping a sizing die that is putting a wicked ring at the junction of the neck and taper. Thought lapping the die at that junction of neck and the taper angle would solve that issue. But I'd like to get the taper angle correct.

I guess I could use a case filled with soft lead but I'm thinking the brass would wear much faster than the sizing die.

[Tom Myers]

Deleted (Duplicate)

[Tom Myers]

[QUOTE=SgtDog0311;3415820]Tom, hoping you see this - any idea what the taper angle is on the tapers body of a 40-65 case? ****************
But I'd like to get the taper angle correct.QUOTE]

SgtDog,

The angle formed at the junction of the case body taper and the neck on my Ron Long reamer calculates out to 1.330°. (included angle is 2.660°)

Your chamber my differ slightly depending on the configuration of the chamber mouth and length of the neck area.

If you do not need to be ultra precise, this angle may be approximated from the measurements of a fired, unsized case. The case is thicker at the web portion than at the neck end so the fired case web area will not have expanded as much as the neck area and you will need to add approximately 0.001" to the web measurement.

Using a micrometer, measure the case diameter at the point on the case web where the taper begins to slope toward the neck.
Add 0.001" to the web diameter, divide by w, make a note of that value and label the value "WR" (web radius).
WR := (0.491" + 0.001") / 2 = 0.246".

Measure the case diameter at the point on the case at the junction of the taper and the neck.
Divide the neck diameter by 2, make a note of that value divide by 2 and label the value "NR" (neck radius).
NR := 0.430" / 2 = 0.215"

Next, using a set of calipers, measure the distance between the web and neck diameters, make a note of that value and label it "TL" (taper length)
TL := 1.335"

Now, subtract the neck radius "NR" from the web radius "WR" and divide by the taper length "TL". Make a note of this result and label it as "S" (slope).
0.246 - 0.215 = 0.031
S := 0.031 / 1.335 = 0.023221

Finally, if you have access to a scientific calculator, press "shift" + "tan" keys, enter the slope value "S" and press "Exe". This will give you the ArcTan value of the slope which is the angle formed by case taper and neck.
ArcTan(0.023221) = 1.33°

If you do not have a scientific calculator, ( for very small angles such as this ), simple arithmetic may be used to find the angle of the slope.

Multiply the slope "S" by 180° and divide that product by "Pi" (3.14159) to arrive at a very close approximation of the angle.
0.023221 X 180 / 3.14159 = 1.33°
Included angle is 2.66°

Click the image below to view the necessary measurements.

Hope this helps.


151977

[SgtDog0311]

Thanks Tom, hadn't thought of the calculations you used. Was thinking of drawing it out on paper and using s protractor but didn't have even that here at the cabin. Thanks for taking the time. Now I need to find someone with a lathe:-)). Appreciate it!!