Case Bulge, is this it? And, should I worry?

Hi, Cub:
This sounds like the Lee-Enfield .303 bulge. The chamber is oversized and the cartridge is lying on the bottom, unless the extractor is pushing it elsewhere. The firing pin nails it in place long enough for the brass on top of the case to bulge up to the top of the chamber. The bottom side stays straight.

The .303 solution is mapping tape. It's 1/16th wide and a wrap just ahead of the rim adds .008". This centres the case in the chamber and you only have to do it once if you neck size. Once you get the length right, so the ends almost butt, you can do a box in a couple of minutes and it's a lot nearer than masking tape. It's an old British trick. I use Geotape, made in the USA, and a good stationary store should have it. The roll I bought cost $5 a while back and should do 450 .303 cases.

Somewhere I read that the original .45 Colt cases had a slight taper, and carbide dies overdo the base of the case. The author (Dave Scoville???) used a steel die with the proper taper for reloading for an old Colt, IIRC.

Bye
Jack

You're probably around max (don't know Lil gun) with the 300grs. Ken Waters was doing those vels with 225gr Speers. (Pet Loads 1/91) He was pretty conservative with the Trapper he was using, though. I think he was more concerned about case construction rather than carbine construction. He wasn't big on magnumizing the .45 colt for that reason.

That is the "pressure bulge" that you measure for excessive pressure. Waters' process is to fire a factory load and measure the max width at the pressure bulge and compare that to your handloaded. He advises staying within .0010-.0015" expansion, with .0020" being too far. You need a mic for this.

The problem is factory .45s are going to be wimpy, so you might need to build a moderate load baseline.

What cases are you using?

Waters found W-W cases bulged and compressed the extractor groove at the rim (in 1991). Federals, he said were beefier and didn't move as much. Both are far stronger than the older cases. But the FCs were the strongest found.

On another note: What sights are you using on your '92? I have the same in .44mag and I have trouble with the bead front and notch rear (they seem mismatched). I'm planning on adding an AO front blade and maybe later one of their peeps (reluctant to drill the receiver).

Rgds,

- Charlie

Cubman,

While making a bunch of chamber casts with cerosafe I have found that most tubular magazine lever actions have a slightly oblong chamber to aid feeding. The Marlin .32-20 and .25-20 are notable for this. With them it shortens brass life.
When starting our newest project, a .30-30 Ackley Improved we noted this while reaming the chamber. The Model 94 had what we thought was a smooth chamber but the reamer proved otherwise by taking off metal on one side and not the other for quite awhile. Finaly we got down to where the reamer was bigger than the original case and it began to ream all the way around. This was only toward the base. It never did cut 360 degrees right at the base.
If you full length size your cases and measure the pressure ring, how much expansion do you get with your maximum loads?

Hi, Gents:
An out of round chamber is curious. That isn't easy with a conventional reamer. Incidently, I get basically zero runout on my fired .35 Remington cases out of the old Marlin, but both my Remington 700s have about .002" runout.

Feeding taped cartridges isn't a problem in a Lee-Enfeld, but you might have to hand chamber them in your Winchester. Mr. Gates noted that seating the bullet long so it's snug in the throat centres the front end of the cartridge and aids in getting an even expansion.

Sizing the neck to just the base of the bullet is OK for revolver bullets, since recoil trys to pull the bullet. The slamming the bullet takes in a tubular magazine tends to seat a bullet deeper, so I'd like a little more resizing to put a ledge in the case to hold the base of the bullet.

If you work up a load with new brass, you can see the bulge move closer to the rim as you go from min. to max. It's real easy to see with a Lee-Enfield.

Bye
Jack

You will have some pretty warm loads if you want to get 1300 out of a 5.5" barrel. I know it can do more. The technique I mentioned will almost certainly work in your carbine and it will work in your Bisley. Keep in mind, as Jack mentioned, that good bullet pull and a good crimp will be mandatory with this round, whatever you decide to fire it in. If you have problems related to this, it will likely be with your expanding stem, not the resized case diameter. The good news is that you are using Redding dies, and if you have a problem, they will make it right. I have experienced this several times over the years, usually related to something out of the ordinary that I'm trying. I can't say enough about the quality and customer service of this company and it's products. Please let me know what velocities you're getting from both guns. I mainly shoot 300gr XTP-Mags out of my 7.5" Bisley with a healthy dose of 296 behind them. I haven't seen the need for the Partition, as I only use them for deer. I shot a big (175lb dressed)doe in Minnesota last week with that gun, and it just knocked it over. The expansion didn't seem to be extreme, but I'll never know because penetration was complete. I'm interested to see what velocities you get with the powder you're using, as well as if the SD is better than the 296.

Great topic. Good advice all around. I have a few observations:

1. Winchester pistol brass deforms more than rem or Federal.

2. I work with Lil'gun a LOT, and it is a very unusual powder. It gets its power from a
pressure curve that is flatter than traditional powders - a lot of area under it, but not such a high peak. It can show a lot of deformation in soft brass for the peak pressure listed.

3. Your loads sre 1-2 grs over Hodgdon's Max. They list 20.2 grs at 29,800 CUP. This is the limit for the Colt BRASS, but probably not your rifle.

I would trim some 454 Casull brass to Colt length, and try a few to see what happens. These cases are designed for 65000 psi, and very strong in the web. Work up your loads again, as the trimmed Casull cases will have a smaller capacity than the Colts. Remember, the Casull uses small rifle primers. Try for 1500 fps and stop there.

This sounds like a lot of work, compared to just buying the Colt brass, but the Casull cases will last forever at these pressures. If this approach does not work, try Jack's tape method.

Hope this helps.