Sizing straight wall cases.

[Vail Vigilante]

On another thread there was discussion about how much clearance there are in some of these chamber-brass case dimensions. When I used to run my 44 mag at bowling pins I did this. Deprime  as a separate operation.  Figure out how much of your chosen bullets length you want to insert into the case. Set you resize die higher than normal so it sizes just that much of the case plus a tad more to accommodate you crimp. You’ll love it. 

[Widder, SASS #59054]

That might work well in the SAME revolver or rifle.

But, it could be another situation in another firearm.

 

..........Widder

 

[The Original Lumpy Gritz]

What works for one, doesn't for all 

[Pat Riot]

It may not work in all the chambers of the same cylinder. 

[Abilene, SASS # 27489]

Easy enough though to load up a few dummies like that to try in other firearms.

[Ozark Huckleberry]

So, you’re only resizing the part of the case where the bullet seats? Then belling it back out to seat the bullet? I must have missed the thread about the chamber dimensions — what do you gain from not resizing the full length?
 

ETA: okay, found it — sealing the chamber. 

[Vail Vigilante]

Yes, all the rounds have to be from the same gun. My Redhawk that I used to use as a pin gun happened to have chambers that were compatible with each other.  Once I started doing this I noticed a measurable shrinkage in group size. I was able to replicate it on many outings. This is how that Redhawk wanted to be fed. Your mileage might vary. In terms of belling, I only bell the slightest amount, that I need to start the bullet. I give the bell die a "kiss" once it touches the case. If I get seating/material shaving issues, another little kiss. 

[Pat Riot]

2 hours ago, Vail Vigilante said:

Yes, all the rounds have to be from the same gun. My Redhawk that I used to use as a pin gun happened to have chambers that were compatible with each other.  Once I started doing this I noticed a measurable shrinkage in group size. I was able to replicate it on many outings. This is how that Redhawk wanted to be fed. Your mileage might vary. In terms of belling, I only bell the slightest amount, that I need to start the bullet. I give the bell die a "kiss" once it touches the case. If I get seating/material shaving issues, another little kiss. 

Interesting. Thank you. 

[Jon C]

It’s the straight wall version of neck sizing bottleneck brass. 
 

I separate brass by gun for precision rifles and neck size only, but I only do it on 500 Linebaugh and 55K PSI 45 Colt for my Linebaugh and Bowen guns as far as handguns go. 

[Colorado Coffinmaker]

Vigilante

 

Chamber sizing for your Redhawk may well have worked for your handgun.  However, that routine won't do Diddley to stop Blow-By in Rifle Chambers.  In most cases, Handgun chambers and Rifle chambers bear no resemblance to one another.

[Reverend P. Babcock Chase]

Howdy Straitwallers,

 

FYI, I neck size my .45 Colt shells and use a Lyman M die to expand the neck just enough for bullet seating with no shaving. I can use my rounds in all of my .45 Colt guns (2-USFA, 2-Schofields, Percussion Remington conversion, Dragoon conversion, 2-1866's, '73 Uberti Win. and Rossi '92) with no problems. 

 

I have noticed that with CAS level loads, the loaded rounds have a bit of a "wasp waist". It seems that the mild loads are not blowing out the case from the base to where the bullet is seated. Yes, I do get some blow by, but I seem to be able to live with it. That's my situation. It ain't broke so I'm in no rush to fix it.

 

Rev. Chase

[JackSlade]

I have to do this with my .45lc. if I don't resize the bullet seating depth, it'll spin freely after I crimp. 

[Bison Bud]

I guess if your having problems with chamber sealing this might help, but I've reloaded for years and never had the need to neck size a straight walled case.

["Big Boston"]

I'm glad that you restricted this to straight walled cases. If you include 44-40, that is a whole different ball of wax.

 

Carbide sizing dies for straight walled pistol cases was already main stream when I started reloading. Before the carbide die, the sizer was a tapered die. The body was sized less at the web than at the neck. This left the neck small enough to grip the bullet but the body below where the bullet was seated was sized to fit the chamber. A carbide die reduces the entire case the same as the neck. This is usually smaller than the solid web of the case. That is just the way it is, a compromise to having the convenience of a carbide ring doing the sizing. I did notice that Dillon FL dies are a bit more tapered, the size gently tapers to the web, instead of an abrupter step. 

 

None of this was of any consequence to me until I added a Uberti '66 rifle in 38 Spl to my match firearms. Uberti tends to make their rifles with chambers on the large size. Add ammo built on the small side and blow back is the result. IMO, once the body of the case is more than 0.010" smaller than the chamber, you have an issue. At Black Powder of less pressure, physics is working against you. Proper expansion and sealing will not happen. 

 

Tapered Full Length carbide  as opposed to ring type carbide dies are rare and very expensive, so that is not a viable option. I'm not prepared to lube cases, so a steel die is not an option for me. Redding makes a two ring sizer, and I have one on order, I won't comment on it until I actually run it through it's paces. 

 

There is a solution. It has been mentioned and it is somewhat common. The method I use is to back out my carbide sizer to size just slightly more of the case than  the length that the bullet seats into. this leaves a bit of a wasp waist look. In essence this section is about 0.002" to 0.003" less than the diameter of the case with a bullet seated. Below the wasp waist the body of the case remains near chamber size until I crimp with a LEE Factory Crimp die. This die reduces the body to just under cartridge max specification. 

 

The only special steps or adjustments are that the decapping pin needs to be a bit longer than supplied. LEE has a decapping pin, 90783, that fixes that. The other consideration is the FCD. It should be turned down to be in or near contact with the shell plate, to ensure the body is sized. This sizer is also a carbide ring, no lube required here either. 

 

The 38 Special is spec'd rather loose. Cartridge Minimum diameter is 0.373". Chamber Maximum is 0.3849" for a difference of 0.119". And that 12 thousandths of an inch is about what the my real world numbers were. My die sizes near minimum and my cases come out of my rifle at 0.383". 

 

In addition, the industry has moved towards making ammunition brass to near minimum specs. Some of the older brass I've examined was closer to the maximum. This trend is industry wide, and includes bottlenecked rifle cases as well. In the case of hunting rifles, most chambers are close to minimum. For cowboy guns, most revolvers have chambers near minimum, and the Italian cowboy rifles are near maximum or even perhaps a bit larger. Most cowboys want the fired cases to be effortlessly extracted for max speed, minimum effort. 

 

I also use the LEE FCD as a gauge for setting the belling (Dillon) adjustment at the powder stage. I set it so that the belled case is no more than a slight friction into the FCD. This minimizes the amount that the brass at the mouth is worked. 

 

BB

[Cpt Dan Blodgett, SASS #75655]

Sounds like the functional equivalent of necksizeing. As with many things in the world of shooting for accuracy you will find many that swear buy it and other who swear at it. If it works for you great others may not share your success.

["Big Boston"]

On 10/9/2022 at 8:46 PM, Cpt Dan Blodgett, SASS #75655 said:

Sounds like the functional equivalent of necksizing. As with many things in the world of shooting for accuracy you will find many that swear buy it and other who swear at it. If it works for you great others may not share your success.

 

No kidding, sometimes the success I thought I was having, wasn't success at all. At time it's more Krap Shoot than technical. I've changed directions slightly since posting that in September. I bought a Redding Dual Carbide Sizing die. I'm giving that a good evaluation as we "speak". I suppose, technically speaking, what I was doing is sizing the neck one diameter and the body to a slightly larger diameter, using two different dies. Neck sizing "implies" that the body remains unsized, and that is a concept that I do not subscribe to. I'd like to avoid sizing the body of the case excessively, IMHO it does not need to be the same size the neck was before it was expanded with the button and the by seating the bullet.  

 

Back in the day I bought neck sizing dies for my bottleneck rifle calibers, and after testing I quit using them. That was before computers, the internet and such, when you had to learn everything by doing it yourself after reading the magazines and reloading manuals. 

 

That is also why I seldom use the phrases, "You should", "You need to" and such. This game just has too many variables. 

 

BB