We have a genius here who suggested that we are doing things backwards!

He suggested that we start with a short barrel and add to it as we go along!?

You see the sort of nitwits I have to put up with.

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saeed@ emirates.net.ae

www.accuratereloading.com

I poked a lot of fun at him for having it, until I shot it. It is an absolute hoot to shoot. I don't think there are any lands left in the barrel - he sets the grass on fire where he lays it down!

Don

Anyway, the gist of it was a very heartfelt "Thank You" for the data that is in this post. I have been wondering whether or not to cut a few inches off of a 8mm Mauser. I know that this data is not directly applicable, but I used the data to come up with a predictive equation that I will share here in case anyone wants to get a good approximation of what will happen if they modify their barrel. This is not a perfect predictor, but it did an admirable job predicting the velocity of a 19.75 inch Mauser, given the velocity of a 26" Mauser, so it does apply to calibers other than a .223 ...

Vel(L inches) = Vel(22")* exp(-0.519 + 0.04*L - 0.0007499*L^2)

I'm sorry if you aren't into the math, but I felt obliged to at least post the results of my analysis. FYI: this equation does predict that after a certain length, more barrel actually slows you down. I think that this is reality ... although I found it very interesting that that data for the .223 generated a max velocity at 26.7" ... maybe the Mauser's 26" barrel was not just for looks?

I wrote more the first time ... if you have any questions about the model, I'd be happy to try to answer them.

Thanks again for the data ... I'll be going to 18"!
Saands

What I have is a pair of old Swedish Mauser rifles in 6.5x55mm. One has a 24-inch barrel and the other has a 30-inch(!) barrel. One of these will be configured as a "faux scout" rifle with a forward-mounted scope while the other will carry a conventional scope.

Both will be fitted with quick detach mounts, so that a Gemtech TPR-S silencer can be easily moved between the two guns. This silencer will add roughly 9 inches to the length of the weapon -- thus my desire to shorten the barrels and keep the overall length within some kind of reason, yet hopefully without compromising their performance too much.

For legal reasons, 16 1/2 inches is the shortest barrel length that I will consider, but I could allow it to run a bit longer -- especially on the conventionally scoped weapon which I expect will be used for longer range shooting.

Incidentally, I'm told the Swedes actually issued a "cavalry carbine" model with a 17.7-inch barrel, while the 30-inch one was for the infantry. But they later standardized on the 24-inch barrel for all their armed forces.

Also incidentally.... My first choice for this project was a telescoping-design "Reflex" suppressor, which would have added maybe 4 inches to the overall length. I then discovered it is not considered practical to import them from Finland unless you are the FBI, CIA, or DoD.

Fascinating project,can't yet review the results as can't get access.

2 years ago I made up a .243 tikka with an 18" barrel (including chamber) and Vaimeco full bore sound moderator. V.accurate for hunting rifle (5/8" with 60gr sierra HPs) and sounds like an unsilenced 22 rimfire. It's mainly used for deer control in peoples (big) gardens. The reason for the shortening is the moderator is 10" long.

I wanted to reduce muzzle flash and blast without the moderator so the moderator would have less to silence and not fill with unburnt powder (potentialy dangerous)

H322 with 60grainers and N140 with 95grainers keeps things quiet but with good trajectory. Complete elimination of muzzle flash (without moderator) means H322 and min 85gr bullet, trajectory suffers a bit.

quote:

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Originally posted by Zobeid:
..I'm told the Swedes actually issued a "cavalry carbine" model with a 17.7-inch barrel, while the 30-inch one was for the infantry. But they later standardized on the 24-inch barrel for all their armed forces.

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I'll give you a brief history of the Swede Mausers: In 1894, Sweden adopted the m/94 rifle with a 17.7" (450 mm) bbl chambered for 6.5x55. The short barrel was considered non gratis in 1896, when the m/96 rifle and its 29.1" (740 mm) bbl made debut. The m/94 was more or less put aside, but production continued in smaller numbers until the 1920's. For 42 years all was well in the Swedish armed forces, but in the late 1930's the army adopted bicycles for troop transport (not a joke, I swear...) and the length of the standard arm was not really compatible with the steel horses. Enter the m/38: The same rifle but with a 23.6" (600 mm) bbl. These were both of new production and made from existing m/96's - the latter normally referred to as m/96-38's, though the Swedish armed forces never made a distinction between them.

-- Mats

[This message has been edited by Mats (edited 04-28-2001).]

I have a T/C with a 14" barrel, and when loaded with Pyrodex and some tissue paper, I get a ginormous flame out of the barrel, together with an incredible amount of smoke!

I am afraid now we have tried the 700, and managed to get over 2500 fps with a 1000 grains, our appetite has been wet for a more potent cartridge.

I have a 12x3" bar of aluminium, and we are seriously thinking of making a dummy from it for a futute catridge.

We were talking about this with Roy yesterday, and someone here, started saying: "Oh No! No! You're NOT going to make a cartrdge this big! They should chain both of you, lock you up and throw the keys away! You're both STARK, RAVING MAD!"

After that, we have no choice but to make it!

I will post a photo when I finish it.

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saeed@ emirates.net.ae

www.accuratereloading.com

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saeed@ emirates.net.ae

www.accuratereloading.com

We have finished shooting this rifle at 10". The results have been posted on the Reloading section.

The muzzle blast with a 10 inch barrel is horrendous!

Here is a pucture of our new baby. A 700 Nitro Express loaded round is next to it for comparison.

David,

Measurements are 2 1/4 x 9 1/2"!

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saeed@ emirates.net.ae

www.accuratereloading.com