T99 chamber cast

[Toney]

7.62-39 is to short, what about 30ppc? frome the base of the shoulder to where i think the rim should be is around 1.3" that's a 7.7-58 round next to the cast. it's still got the original barrel just got an insert up in the chamber

[swheeler]

Toney; 308x1.5?

[7br]

Isn't the 308x1.5 basically a 30br? There is also a .30 Kern which is close to the 30br. Tom Acheson(sp?) who writes for the IHMSA news plays with a 30kern. I am fairly sure he competes in CBA Bench matches also. If you are interested, you could go over to the IHMSA website and post under the general topics asking about the article..

http://www.aimoo.com/forum/freeboard.cfm?id=388847

[felix]

Mark, it's the case capacity that typically rules for accuracy work. It seems most of the BR case sizes bounce between 28 grains thru 35 with a sharp shoulder. ... felix

[Jumptrap]

The .30 Kern as I understand....is essentially what I'd call a .30 PPC...it's parent case is the 762x39.....which is the parent case of the .22 and 6 m/m PPC's.....well okay, the .220 Russian is the parent but it was sired by 762x39 case..so go figure..which came first the chicken or the egg. The Kern has the shoulder moved forward or back a bit. I have both a .22 and a 6 m/m PPC and if I was going to build a short .30...now that the stars are gone from my eyes.....I'd do a 308x1.5 for pure custom and for ease of everything, I'd build a 762x39 and call it done. I can't understand why anybody would put an insert in that Jap for the 308x1.5......except for one reason....a semi-bad chamber. Most Japs.....for whatever reason....have sloppy chambers in them. The empties fall out lop-sided. There may have been slop engineered in to accomodate dirty and corroded ammo...remember the military doesn't give a damn about empties..the ammo has to always go in and then come out..that's all they care about. Perhaps a previous owner just tried to clean up a sloppy chamber with an insert. I think if it were mine, I'd yank the insert and go back to 7.7...no fly in that ointment to begin with. In fact, I'd buy a new rifle in 7.7 Jap if somebbody would make one! I always bragged that if Remington would make a 700 in 8x57 I'd buy it. They did and I did...may have shot 10 rounds in it!

[StarMetal]

Here's an idea. Instead of the 308 x 1.5 why not the 284 case necked to 30 caliber and cut to 1.5 lenght OR whatever lenght it would take to get that case capacity that Felix mentioned AND it certainly would have a sharp shoulder. huh? huh? What do you fellows think? Felix?

Joe

[TCLouis]

I bought a 99 fairly nicely sporterized. The shop said they were not sure what it was. I smirked at the far lower than normal price and said I did.

So far I have NOT figured it out either.

I have been too lazy to cast chamber but will get to that and post some dimensions!

IT AIN"T a 7.7X58 though!!

[StarMetal]

It's a 30-06 reamer run into the 7.7 Jap chamber.

Joe

[Jeffreytooker]

I have a 30 Kern on a 1909 Argie action. The stock and the barrel are after market. Jump is correct. 30 Kern is a blown out 7.62X39. The Mauser bolt has a long enough extractor to extract the empty case. The case is a bit smaller than the 30 BR. I ended up with 30 Kern because that was the reamer the gunsmith had to finish the 7.62X39 aftermarket barrel.

The 30 Kern was developed for CBA competition. It does not have quite the capacity of the 30 BR which has eclipsed it. 30 BR's are pushing ~214 gr boolets like the Egan MX430 ARD.

It makes a good Cast Boolit rifle for lighter boolits at Cast Boolit velocities. The 308X1.5 is a better case because most bolt rifles are made to fit that case head. My cartridge books are packed for the move next month so I can not find the info I want. However there is a 308 based case that is even shorter than the 1.5.

For Cast Boolits I have found the order to be reversed from what we would think is the way to build a rifle. First Pick the bullet you want. Then find the best mould you can for the bullet. Cast the bullet in the alloy you want. Determine the velocity you want. This will determine the volume of the case you want behind the boolit.

The 30 BR cartridge for CBA competition is not always standard size. Some are a bit shorter or longer because the shooter is trying to get a better match between boolit, case and powder.

I will now get off of my soap box.

Jeffrey

[Ricochet]

How about the .300 WSM shortened to 1.5"? That'd be stubby.